Trending Topics pieces (Article Analyses, Evidence Clips and Other Topics) are published in timely response to recent media and journal articles, position statements, clinical guidelines, etc. Since they are based on the most recent evidence/publications, they may not be consistent with PEN evidence in other PEN content areas. As soon as possible, when this occurs, the PEN content will be reviewed and updated as needed.
Should You Strike "Boosting Your Immune System" from Your Vocabulary? Avoiding "Science-ploitation"
In a recent podcast, Dr. Jen Gunter describes the problems with the phrase “boosting the immune system” (1). The PEN Team wondered if the podcast concepts might be useful to dietitians when clients ask about “immune-boosting” foods and supplements.
Dr. Gunter interviewed Dr. Katherine Gundling, an immunologist, who described the fallacies behind the immune “boosting” concept, primarily that the immune system cannot be safely and effectively boosted. Her main point was that the immune system is continually balanced between its numerous parts. She described how artificially boosting one part of the immune system could be a problem, especially when another part of the immune system might be needed to fight an infection. An example of immune system unbalance that results in a negative outcome occurs in severe cases of COVID-19 when some parts of the immune system become overactive, causing excess inflammation, which can lead to death.
The details of inaccurate claims
Advertisements tell us that our immune system needs a boost and then that the product being promoted will do this boosting (1,2). These promotions prey on our fears of illness while misrepresenting how the immune system works and its complexity (1). Dr. Gunter noted that in the U.S. nutrition supplements do not have the same testing and scrutiny as is required for drugs, and that most supplements do not have robust studies to back up either the claims made or even that they are safe (1). Regulations for nutrition supplements vary by country, and dietitians should be aware of regulations pertaining to supplements in the country where they practice.
Dr. Gunter cited an older study where dietary supplements were identified as likely to have caused 20% of liver injury in the U.S (3). She also cited a more recent study that suggested that dietary supplements lead to 23,000 emergency room visits per year (4). She interviewed Timothy Caulfield, a Canadian professor of law, who pointed out that the trends to promote supplements have increased over the past decade, especially through social media (1). Some celebrities have created brands of supplements and have made promoting pseudoscience a big business (1). These promotions use science-ish words, which Caulfield refers to as science-ploitation (5). According to Caufield, people are swayed by this clever marketing, but this science-ploitation uses inaccurate and misleading information to create the illusion that those who use science-ploitation have in-depth knowledge (5).
Dietitians know the importance of healthy eating to support the immune system and for well-being. While you cannot “boost” your immune system, other recommendations mentioned in the podcast include:
- getting adequate sleep
- getting adequate exercise
- treating chronic diseases when they occur
- stopping smoking/vaping
- washing hands
- getting vaccinated (1).
Points dietitians can use to help clients separate medicine from marketing include (5):
- When promoters use science-ish words, it doesn’t necessarily mean that what they are promoting is based on science.
- Be wary if someone is trying to sell you something; they may not have your best interests at heart.
- Be skeptical of anecdotes and testimonials; they are not scientific evidence.
- Look for information from reliable sources. Stop and think before you share something with someone else; it could be misinformation. Misinformation is like a virus; if you stop sharing it, you help to stop the spread.
See Additional Content/Resources:
Looking for more information on the immune system and/or dietary supplements? Search
the PEN website. There are more than 220 practice questions on dietary supplements and 29 practice questions on immunity.
- Gunter J. Can you boost your immune system? Body Stuff with Jen Gunter. Undated. [cited 2021 Jul 21]. Available from: https://podcasts.apple.com/ca/podcast/can-you-boost-your-immune-system/id1566425638?i=1000525688537
- Rachul C, Marcon AR, Collins B, Caulfield T 5. COVID-19 and 'immune boosting' on the internet: a content analysis of Google search results. BMJ Open. 2020 Oct;10(10):e040989. doi: 10.1136/bmjopen-2020-040989. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/33109677/
- Azadniv M. Klinge CM, Gelein R, Carstensen EL, Cox C, Brayman AA, et al. A test of the hypothesis that a 60-Hz magnetic field affects ornithine decarboxylase activity in mouse L929 cells in vitro. Biochem Biophys Res Commun. 1995 Sep 14;214(2):627-31. doi: 10.1006/bbrc.1995.2332. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/7677775/
- Geller AI, Shehab N, Weidle NJ, Lovegrove MC, Wolpert BJ, Timbo BB, et al. Emergency Department Visits for Adverse Events Related to Dietary Supplements. N Engl J Med. 2015 Oct 15;373(16):1531-40. doi: 10.1056/NEJMsa1504267. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/26465986/
- Rendely A. Why social media needs less ‘science-ploitation’ and more hard facts. TVO. 2019 Apr. Available from: https://www.tvo.org/article/why-social-media-needs-less-science-ploitation-and-more-hard-facts
Can Coffee Prevent Chronic Liver Disease?
Recent headlines (1,2) attest that drinking coffee prevents chronic liver disease, based on a recently published study (3). The PEN Team set out to investigate whether the evidence supports these cause-and-effect statements.
The study, published in the Journal of BMC Public Health, looked at 384,818 coffee drinkers and 109,767 non-coffee drinkers against estimated hazard ratios (HR) of incident chronic liver disease (CLD), incident CLD or steatosis, incident hepatocellular carcinoma (HCC) and deaths from CLD over a 10-year period (3). The authors concluded that “…the finding that all types of coffee are protective against CLD is significant given the increasing incidence of CLD worldwide and the potential of coffee as an intervention to prevent CLD onset or progression”.
This study’s findings (3) should be considered low certainty evidence (the true effect may be quite different from the estimated effect (4)). With only low certainty evidence, the PEN Team questions whether any recommendations should be made on the basis of this research. Since there isn’t high certainty evidence, a recommendation for people to consume coffee to prevent CLD cannot be made.
Why is this research low certainty evidence?
The main reason that this study’s findings are low certainty evidence is due to serious study limitations, primarily based on its observational design. The research participants were not randomized for coffee consumption. The participants chose their coffee consumption and then described it to researchers.
It is possible that the protective factor attributed to coffee is actually something else. People choose their lifestyles and food choices based on many factors. In this type of study, the observed relationship could be due to some other factor that is common among people who drink coffee. The study authors adjusted their findings for some important CLD predictors (including alcohol-related liver disease, BMI, alcohol intake, diabetes and smoking); however, there may be some other factor(s) that they did not adjust for that could be the actual causal factor(s).
Other weaknesses that raise concerns about how much confidence should be put in this study’s findings are (3):
- There was no clear dose-response effect, and the researchers did not perform a statistical test to check for a dose-response effect of better outcomes associated with higher coffee consumption.
- The study used self-reported, single measurements only of coffee, alcohol and tobacco intakes (3). Due to social desirability bias, people do not always accurately report their intakes (5).
- The study did not provide information on associations with coffee consumption and the various causes of CLD (3). For example, perhaps people who drink more coffee are less likely to be exposed to a virus that causes CLD.
- Although this represents a large cohort of 500,000 participants, this study was at risk of selection bias since only about 10% of those invited to participate agreed to participate.
The PEN Team is concerned that the research paper title, “All coffee types decrease the risk of adverse clinical outcomes in chronic liver disease”, may imply that this is high quality research. The media made cause-and-effect headlines, including that coffee “cuts risk”, “reduces your risk”, “may help avoid chronic liver disease” (1,2). A better title would be: Potential association of coffee consumption with reduced risk of CLD, which matches the study’s conclusion.
Other meta-analyses of observational studies have suggested that coffee consumption is inversely associated with lower rates of liver cancer (6) and non-alcoholic fatty liver disease (NAFLD) (7). This cohort study expanded this association to all types of coffee, including decaffeinated coffee (3).
Given the limitations of these observational studies, international caffeine guidelines
should be followed to guide coffee consumption. It would be important for future research to consider additional non-liver outcomes to ensure that recommendations can be safely made to use coffee as a preventive agent for liver diseases.
See Additional Content:
- LaMotta S. Drinking coffee of any type cuts risk for liver problems, study says. CTV News. 2021 Jun 22. Available from: https://www.ctvnews.ca/health/drinking-coffee-of-any-type-cuts-risk-for-liver-problems-study-says-1.5480329
- Charles K. Drinking coffee or decaf may help avoid chronic liver disease. NewScientist. June 22, 2021 Jun 22. Available from: https://www.newscientist.com/article/2281765-drinking-coffee-or-decaf-may-help-avoid-chronic-liver-disease/
- Kennedy OJ, Fallowfield JA, Poole R, Hayes PC, Parkes J, Roderick PJ. All coffee types decrease the risk of adverse clinical outcomes in chronic liver disease: a UK Biobank study. BMC Public Health. 2021 Jun;21(1):970. https://doi.org/10.1186/s12889-021-10991-7. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/34154561/
- Siemieniuk R, Guyatt G. What is GRADE? BMJ best practice toolkit. 2021. Available from: https://bestpractice.bmj.com/info/toolkit/learn-ebm/what-is-grade/
- Graeff TR. Response bias. In the Encyclopedia of Social Measurement. 2005. Available from: https://www.sciencedirect.com/referencework/9780123693983/encyclopedia-of-social-measurement
- Bhurwal A, Rattan P, Yoshitake S, Pioppo L, Reja D, DellatoreInverse P, et al. Association of Coffee with Liver Cancer Development: An Updated Systematic Review and Meta-analysis. J Gastrointestin Liver Dis. 2020 Sep 9;29(3):421-8. doi: 10.15403/jgld-805. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32830818/
- Chen YP, Lu FB, Hu YB, Xu LM, Zheng MH, Hu ED. A systematic review and a dose-response meta-analysis of coffee dose and nonalcoholic fatty liver disease. Clin Nutr. 2019 Dec;38(6):2552-7. doi: 10.1016/j.clnu.2018.11.030. Epub 2018 Dec 4. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/30573353/
Vitamin B12 in Pregnancy
Concern with a Systematic Review’s Conclusions
A concern about vitamin B12 deficiency causing adverse outcomes in pregnant women, particularly of South Asian descent, prompted us to look more closely at this hot topic. We identified a systematic review (SR) that focused on the vitamin B12 status of women and infants living in India (1). The review concluded that low maternal vitamin B12 status is associated with adverse maternal and child health outcomes and the review authors noted: "Based on the quality of evidence reviewed, we recommend the addition of vitamin B12 to various nutritional programs in India for children, adolescents, women in the reproductive age group, pregnant and lactating women. This public health measure would help in reduction in risk of NTD and improving birth weight in the offspring” (1). After reviewing the SR, the PEN® Team has concerns about its quality and question the accuracy of the authors’ conclusions.
More Details on the Findings
What potentially brings the SR’s conclusions into question is that the SR’s authors did not follow the SR guidelines that they stated they followed in the preparation of their summary statements. The authors rated evidence for birth weight and neural tube defects as “high quality evidence” despite the fact that some of the evidence they found was from indirect studies (1):
- A food supplementation in a pregnancy study did not mention vitamin B12 or cobalamin (2).
- Some included studies evaluated the effects of various foods supplemented in pregnancy that differed in other nutrients without much difference in vitamin B12 intakes (3,4).
- Some of the cited studies’ results contradict their conclusion about higher birth weight after vitamin B12 (3-5).
- The evidence for neural tube defects (NTD) was rated as high (1) despite the lack of temporal evidence of vitamin B 12 deficiency data from the same point in pregnancy that the NTD occurred. Their strongest evidence for an association between vitamin B12 deficiency and NTD was the indirect association between a gene polymorphism that produces lower intracellular vitamin B12 concentrations (1) was not direct evidence that NTD can be prevented by adequate vitamin B12 status.
While it is important for the SR authors to include studies even if the results do not agree with other studies, it is not appropriate in these cases to rate the summary conclusions as “high quality evidence”. The SR authors should also consider evidence that is not direct, which they did; however, this indirect evidence needs to be considered weak support for the topic under study. Overall, with these identified weaknesses, the PEN Team does not have confidence in the findings or conclusions from this SR.
However, the authors raise the concern about women of South Asian descent being more vulnerable to vitamin B12 deficiency in pregnancy. There are studies that offer support to this concern, including:
- A Canadian study that addressed the question of whether some pregnant women are at higher risk of vitamin B12 deficiency found that some women (18%) were deficient based on their blood levels, and those who were deficient were from an ethnic group that was more likely to be vegetarian (6). They examined the vitamin B12 status among a convenience sample of 320 pregnant women living in Vancouver using both plasma vitamin B12 and methylmalonic acid (a marker for vitamin B12 status). They found 18% and 33% of the women had plasma B12 levels in the deficient and suboptimal ranges and 2% had methylmalonic acid levels suggestive of deficiency. The odds of being B12 deficient were about 10-times higher for those women who self-identified as South Asian (noted to frequently be vegetarian) compared to the other ethnicities, likely due to vegetarian eating patterns. Those taking vitamin B12 supplements had 69% lower odds of having vitamin B12 deficiency.
For pregnant women who consume animal products including meat, poultry and fish, meeting recommended B12 levels can be easily met. For pregnant women who follow a vegan diet, sources of B12 from fermented foods, including nori, chlorella, spirulina and algae and unfortified nutritional yeast cannot be relied on as adequate sources of vitamin B12. As per PEN recommendations, dietitians should encourage pregnant women who follow vegetarian diet patterns to regularly consume foods fortified with vitamin B12 or to take a vitamin B12 supplement (7).
The Institute of Medicine International Dietary Reference Values are 2.6 for pregnancy and 2.8 ug/day in lactation (8).
See Additional Content:
- Behere RV, Deshmukh AS, Otiv S, Gupte MD, Yajnik CS. Maternal vitamin b12 status during pregnancy and its association with outcomes of pregnancy and health of the offspring: a systematic review and implications for policy in India. Front Endocrinol (Lausanne). 2021 Apr 12;12:619176. doi: 10.3389/fendo.2021.619176. eCollection 2021. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/33912132/
- Rao S, Yajnik CS, Kanade A, Fall CH, Margetts BM, Jackson AA, et al. Intake of micronutrient-rich foods in rural Indian mothers is associated with the size of their babies at birth: Pune Maternal Nutrition Study. J Nutr. 2001 Apr;131(4):1217-24. doi: 10.1093/jn/131.4.1217. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/11285330/
- Potdar RD, Sahariah SA, Gandhi M, Kehoe SH, Brown N, Sane H, et al. Improving women's diet quality preconceptionally and during gestation: effects on birth weight and prevalence of low birth weight--a randomized controlled efficacy trial in India (Mumbai Maternal Nutrition Project). Am J Clin Nutr. 2014 Nov;100(5):1257-68. doi: 10.3945/ajcn.114.084921. Epub 2014 Sep 17. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/25332324/
- Lawande A, Gravio CD, Potdar RD, Sahariah SA, Gandhi M, Chopr H, et al. Effect of a micronutrient-rich snack taken preconceptionally and throughout pregnancy on ultrasound measures of fetal growth: The Mumbai Maternal Nutrition Project (MMNP). Matern Child Nutr. 2018 Jan;14(1):e12441. doi: 10.1111/mcn.12441. Epub 2017 Mar 2. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/28251804/
- Duggan C, Srinivasan K, Thomas T, Samuel T, Rajendran R, Muthayya S, et al. Vitamin B-12 supplementation during pregnancy and early lactation increases maternal, breast milk, and infant measures of vitamin B-12 status. J Nutr. 2014 May;144(5):758-64. doi: 10.3945/jn.113.187278. Epub 2014 Mar 5. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/24598885/
- Jeruszka-Bielak M, Isman C, Schroder TH, Li W, Green TJ, Lamers Y. South Asian ethnicity is related to the highest risk of vitamin b12 deficiency in pregnant Canadian women. Nutrients. 2017 Mar 23;9(4):317. doi: 10.3390/nu9040317. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/28333089/
- Dietitians of Canada. How can vitamin B12 requirements be met on a vegetarian diet throughout the life cycle? In: Practice-Based Evidence in Nutrition [PEN]. 2021 Apr 26. Available from: https://www.pennutrition.com/KnowledgePathway.aspx?kpid=2709&pqcatid=145&pqid=28832. Access only by subscription.
- Institute of Medicine. Dietary reference intakes: the essential guide to nutrient requirements. Vitamin B12. Washington, DC: The National Academies Press; 2006. Available from: https://www.nap.edu/read/11537/chapter/19.
Consumers’ Feelings About Meat and Meat Alternatives: Can Framing Influence Perception?
In a recent study, researchers used a mixed-methods approach to examine consumer perceptions of meat and meat alternatives and whether framing products as part of a meal, rather than in isolation, influences consumer perceptions (1). The study findings provide insights into how meat alternative products may be positioned to appeal to various consumer profiles and also provide a basis for further research. The following analysis by a dietetic student looks at the key aspects of this study.
FindingsParticipants were invited via social networking websites to take part in two online surveys on consumers’ perceptions of eight food products (red meat, white meat, fish and seafood, insects, legumes, tofu, seitan and lab-grown meat). The first survey asked participants about their attitudes towards these foods, while the second survey (n=285) evaluated consumers’ attitudes towards meats and meat alternatives when presented as either part of a meal or a stand-alone product. The authors concluded that how these foods are presented alters consumer attitudes towards and possibly the adoption of meat alternatives.
What This Means
The authors suggested that consumers can be categorized into three different consumer profiles based on their feelings towards meat and meat alternative products: individuals uninterested and/or disgusted by meat alternatives due to perceived taste preferences (55.8%); individuals open to meat alternatives due to the perceived health benefits of meat alternatives (26.1%); and individuals who prefer meat alternatives and/or feel disgust towards meat consumption due to ethical concerns (18.1%). These profiles may be useful in targeted meat alternative marketing and promotional initiatives as detailed groupings allow the industry to engage consumer preferences through specific messaging and tactics. The results suggest that when a meat alternative is presented as part of a meal instead of a stand-alone product, it can improve the appeal of meat alternatives and elicit more favourable perceptions across profiles.
The findings presented in this study may not be representative or generalizable to diverse populations given that:
- All study participants self-selected in this study on attitudes about meat alternatives were the same nationality (Portuguese).
- The majority were highly educated, female and residing in urban areas.
- A disproportionate number of participants identified as vegetarians or vegans.
- The questions were about attitudes toward foods without participants being presented with any foods.
- The study relied upon participants’ pre-existing knowledge about the food products included in the surveys.
- The methods used to obtain participants (social networking websites and mailing lists) may have influenced the results.
The study was funded through a grant awarded to Catarina Possidonio by Fundaç˜ao para a Ciˆencia e Tecnologia.
Written by Natalie Johnston, BMOS, BSc Candidate, Brescia College University. Reviewed by Lisa Doerr, MSc, RD and Tanis Fenton, PhD, RD, FDC.
- Possidónio C, Prada M, Graça J, Piazza J. Consumer perceptions of conventional and alternative protein sources: a mixed-methods approach with meal and product framing. Appetite. 2021 Jan;156(104860):1-10. doi.org/10.1016/j.appet.2020.104860. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32916208/
U.S. Report of Heavy Metals in Manufactured Infant Foods
A U.S. report finds heavy metals in manufactured infant foods. Should we be concerned? Are heavy metals present in infant foods at unsafe levels? What should dietitians be advising parents to do? The PEN Team went looking for answers.
The Subcommittee on Economic and Consumer Policy of the U.S. House of Representatives released a report stating that some products and ingredients marketed for infants contained high levels of toxic heavy metals (1). Assuring the safety of infant foods is essential for the healthy development of children, so the PEN Team decided to review the Committee’s report to determine the extent of the toxic heavy metals in foods manufactured for infants.
The heavy metals examined in the report included arsenic, lead, cadmium and mercury (1). These findings were gathered from four food manufacturers’ submitted test results. Looking at Table 1
, arsenic levels in the tested infant food products were found to be as high as 180 parts per billion (ppb), lead as high as 50 ppb, cadmium 344 ppb and mercury, although rare, was as high as 10 ppb.
To determine if the levels of heavy metals were too high, the report presented a number of benchmarks (1). The main benchmark used for each of the heavy metals was the U.S. Food and Drug Administration (FDA) established standards for maximum allowable levels in drinking water (see Table 1
). However, Codex (Food and Agricultural International Food Standards) specifies that the maximum acceptable level for arsenic in food is 20 times the maximum acceptable level in water and for lead the difference is 10 times (2). The PEN Team wonders about using maximum levels for drinking water as the basis of comparison, since Codex guidelines recognize that water levels need to be lower than food, as water is consumed in greater quantities than food (2). We also noticed that none of the food products reported exceeded the Codex maximum levels for these metals in foods (see Table 1
When the PEN Team took a closer look at the Subcommittee’s report, we discovered that most of the testing for heavy metals was on the individual ingredients used to create the infant food products (1). Few finished food products were specifically examined. The ingredient with the highest amount of arsenic was amylase enzyme and the highest amount of lead was in one of the cinnamon samples (1). Both of these ingredients are likely present in very small quantities in foods. Therefore, one cannot generalize the findings of high heavy metal contents of individual ingredients directly to the finished food product because we cannot know how high the true amounts of heavy metals are in infant foods when only the contents of ingredients are reported.
Some ingredients that might be used in larger quantities had high amounts of arsenic (rice is known to accumulate arsenic as the plant grows) (3). For example, samples of organic rice flour from two different food manufacturers had amounts of 570 ppb (Beechnut sample) and 390 ppb (Hain sample) (1). These samples were both high compared to the FDA recommendation of no more than 100 ppb for infant rice/rice products (4) and Codex maximum level of 200 ppb for rice (2). However, those samples were unusually high as 92% of the other rice flour samples had arsenic between 100 and 200 ppb. Foods marketed as “organic” were as high or higher than those produced through conventional agriculture (1).
Table 1: Comparison of the Subcommittee Report Findings with International and U.S. National Guidelines for the Maximum Levels of Heavy Metals for Drinking Water and Foods
In Parts per Billion
Subcommittee Report: Maximum in an Infant Food (1)
Codex: Food Maximum Level (2)
FDA: Food Maximum Level for Infant Food (4)
Codex: Drinking Water Maximum Level (2)
FDA: Drinking Water Maximum Level (4)
100 for infant rice cereals
100 for foods,
200 for grains, 500 for meats
Establishing safety levels of heavy metals in foods is very complex. It requires careful consideration of many factors, including the concentration in the food, the amount consumed and its frequency, and the body size of the consumer (5). For a comprehensive review of the safety of arsenic in infant foods, see the PEN Trending Topic: Do New Parents or Parents-to-be Need to be Concerned About Dietary Arsenic Exposure?
Globally, the concentration of arsenic in rice and rice products is a common concern (5). In contrast to the findings of the Subcommittee report, studies from Health Canada and Food Standards Australia New Zealand found that the arsenic content of rice is lower than maximum permitted levels (6,7). In the U.K. where arsenic in some samples of rice exceeded the European Union Standards, the recommendation is to limit rice fed to infants to 20 g/day (8).
Rice, products made from rice, and fruit juices are foods that are typically higher in arsenic and these foods have historically been recommended or given to young children (5). Current advice is to give young children some meat as a source of easily absorbed iron, to offer a variety of infant cereals and grains, and to limit fruit juice (9). These strategies will help to keep young children’s arsenic intakes lower (5).
Until safe standards are established, the PEN Team recommends:
- People of all ages eat a variety of foods (10).
- Rather than purchasing foods specifically marketed for infants/children, young children's transition to eating a variety of food is best supported through family foods. Infants have difficulty obtaining sufficient iron, so dietitians should emphasize the importance of iron-rich foods (meat, meat alternatives and fortified infant cereals made from a variety of grains) (9).
- Dietitians are also encouraged to advocate for the development of heavy metal national standards for infant foods in all countries, including:
- safe limits determination
- standardization of testing
- transparency and labelling of amounts in manufactured infant foods.
The PEN Team would like to thank Becky Blair for contributing to this Trending Topic.
- Subcommittee on Economic and Consumer Policy. Committee on Oversight and Reform. U.S. House of Representatives. Baby foods are tainted with dangerous levels of arsenic, cadmium, lead and mercury. 2021 Feb 4. Available from: https://oversight.house.gov/sites/democrats.oversight.house.gov/files/2021-02-04%20ECP%20Baby%20Food%20Staff%20Report.pdf
- Food and Agriculture Organization, United Nations. General standard for contaminants and toxins in food and feed (CODEX STAN 193-1995). Adopted in 1995. Revised in 1997, 2006, 2008, 2009. Amendments 2010, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019. Available from: http://www.fao.org/fao-who-codexalimentarius/sh-proxy/en/?lnk=1&url=https%253A%252F%252Fworkspace.fao.org%252Fsites%252Fcodex%252FStandards%252FCXS%2B193-1995%252FCXS_193e.pdf
- U.S. Food and Drug. Arsenic in rice and rice products risk assessment. 2016. Available from: https://www.fda.gov/food/science-research-food/cfsan-risk-safety-assessments (under Downloads)
- U.S. Food and Drug Administration. Metals in your food. 2020 Aug 24. Available from: https://www.fda.gov/food/chemicals-metals-pesticides-food/metals-and-your-food
- Dietitians of Canada. Trending Topic - Do new parents or parents-to-be need to be concerned with dietary arsenic exposure? In Practice-based Evidence in Nutrition [PEN]. May 2018. Available from: https://www.pennutrition.com/resourcestools.aspx?trcatid=496&trid=26806&sr=arseniccbabiedcbabiescbabycbabying. Access by subscription only.
- Canadian Food Inspection Agency. 2011-2013 arsenic speciation in selected foods. 2018 Sep 4. Available from: https://www.inspection.gc.ca/food-safety-for-industry/food-chemistry-and-microbiology/food-safety-testing-bulletin-and-reports/arsenic-speciation-in-selected-foods/eng/1467179764138/1467179789317
- Food Standards Australia New Zealand. Arsenic. January 2020. Available from: https://www.foodstandards.gov.au/consumer/chemicals/arsenic/Pages/default.aspx#:~:text=There%20are%20limits%20in%20the,a%20level%20of%202mg%2Fkg
- Menon M, Sarkar B, Hufton J, Reynold C, Reina V, Young S. Do arsenic levels in rice pose a health risk to the UK population? Ecotoxicol Environ Saf. 2020 Jul 1:197:110601. Available from: https://pubmed.ncbi.nlm.nih.gov/32302858/
- Dietitians of Canada. Infant Nutrition - Complementary Feeding Summary of Recommendations and Evidence. In: Practice-based Evidence in Nutrition [PEN]. 2019 Aug 06. Available from: https://www.pennutrition.com/KnowledgePathway.aspx?kpid=2503&trcatid=42&trid=2514 Access by subscription only.
- Dietitians of Canada. International Dietary Guideline Collection. In: Practice-based Evidence in Nutrition [PEN]. 2021 Jan 11. Available from: https://www.pennutrition.com/KnowledgePathway.aspx?kpid=3127&trid=19399&trcatid=27 Access by subscription only.
Vitamin D and COVID-19: Do Latest Studies Support Supplementation?
To date, research on vitamin D supplementation and COVID-19 outcomes has been limited, so the PEN Team reviewed two recent studies on vitamin D and COVID-19 to see what, if anything, has changed.
Conversations continue on social media about the potential role of vitamin D supplementation in the prevention and treatment of COVID-19. The PEN Team noticed that a common rationale was that patients with COVID-19 tended to have lower vitamin D status (25(OH)D levels). We decided to take a look at two recent studies that reported this connection to determine if the results support vitamin D supplementation to improve COVID-19 outcomes.
First, we looked at an observational study by De Smet et al. that noted that patients with COVID-19 had progressively lower 25(OH)D levels with more severe COVID respiratory disease (1). The study authors also observed that those with vitamin D deficiency were almost four times more likely to die (adjusted odds ratio [OR] 3.87; 95% confidence interval [CI], 1.30 to 11.55). Vitamin D deficiency was prevalent among the patients with COVID-19 infections, more so among the men (67%) than among the women (47%). These researchers adjusted for several variables that are risk factors for COVID-19 mortality (age, ethnicity, chronic lung disease, coronary artery disease/hypertension, diabetes and extent of lung damage).
From other vitamin D research, we know that the marker for vitamin D status (25(OH)D) can be lowered by infections (2). Therefore, low 25(OH)D levels may not reflect poor vitamin D status in a person with an infection. De Smet et al. were not able to determine whether what looked like a vitamin D deficiency was actually a nutritional deficiency or whether the COVID-19 infection lowered the participants 25(OH)D, making these patients appear to have a vitamin D deficiency (1). For this reason, this observational study does not provide evidence that vitamin D supplementation would be helpful for improving outcomes of a COVID-19 infection.
The second study we examined was a randomized control trial of vitamin D supplementation in people with mild symptomatic and asymptomatic COVID-19 infections. Rastogi et al. randomized 40 people with mild COVID-19 infections to 60,000 IU/day of vitamin D3 or placebo for seven days (3). The researchers observed that more participants in the intervention group became COVID-19 RNA negative before day 21 compared to participants in the control arm (62.5% versus 20.8%, P<0.018). Vitamin D supplementation lowered fibrinogen levels significantly but not the other inflammatory markers (SARS-CoV-2 RNA, D-dimer, procalcitonin CRP and ferritin). These researchers only reported differences in indirect markers (3) and did not report World Health Organization-recommended patient-important outcomes (patient survival and patient health care system use over the course of clinical illness) (4). The PEN Team thinks that this trial does not answer the question of whether vitamin D supplementation improves COVID-19 outcomes.
What This Means
After reviewing these studies, the PEN Team has two key questions:
1. What is the relationship between vitamin D deficiency and COVID-19 severity?
2. What is the impact of vitamin D supplementation on patient-important outcomes, such as disease severity, hospitalization and death?
Before dietitians can make recommendations on the use of vitamin D supplementation to improve COVID-19 outcomes, randomized control trials examining the prevention of COVID-19 (including severe COVID-19) and the treatment of COVID-19 with patient-important outcomes are needed.
- De Smet D, De Smet K, Herroelen P, Gryspeerdt S, Martens GA. Serum 25(OH)D Level on Hospital Admission Associated With COVID-19 Stage and Mortality. Am J Clin Pathol. 2020 Nov 25:aqaa252. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7717135/
- Hernández-Álvarez E, Pérez-Barrios C, Blanco-Navarro I, Pérez-Sacristán B, Donoso-Navarro E, Silvestre RA, et al. Association between 25-OH-vitamin D and C-reactive protein as a marker of inflammation and cardiovascular risk in clinical practice. Ann Clin Biochem. 2019 Jul;56(4):502-7. Available from: https://pubmed.ncbi.nlm.nih.gov/31043057/
- Rastogi A, Bhansali A, Khare N, Suri V, Yaddanapudi N, Sachdeva N, et al. Short term, high-dose vitamin D supplementation for COVID-19 disease: a randomised, placebo-controlled, study (SHADE study). Postgrad Med J. 2020 Nov 12:postgradmedj-2020-139065. Abstract available from: https://pubmed.ncbi.nlm.h.gov/33184146/
- WHO Working Group on the Clinical Characterisation and Management of COVID-19 infection. A minimal common outcome measure set for COVID-19 clinical research. Lancet Infect Dis. 2020 Aug;20(8):e192-e197. Abstract available from https://pubmed.ncbi.nlm.nih.gov/32539990/
USDA Dietary Guidelines
Food Trends in 2021
During the COVID-19 pandemic last year, the interest in personalized nutrition, a healthy gut and the immune system and related nutrients and supplements increased, as did cooking more. These trends appear to be continuing into 2021 based on information from Forbes
and Food Insight
, and in some of the links below. Expect to also see an increase in food costs and more interest in reducing waste and recycling, and support for local businesses.
Check out a few other predictions:
Happy New Year!
Consumption of Ultra-Processed Foods Trending Down But Still High
Ultra-processed foods (UPFs) are back in the news
following the publication of two papers this year, both using dietary 24-hour recall data from the Canadian Community Health Survey (CCHS). One paper compared the intake of UPFs and the nutrition profile of the diet between 2004 and 2015 (sample size of 33,924 for the 2004 survey and 20,080 for the 2015 survey; breastfeeding children excluded) (1). The other paper looked at a cross-section of the 2015 UPF consumption data (sample size of 13,608, aged 19 years or older) with associated health effects (2).
In 2019 the PEN® Team wrote two Trending Topics:
The studies reviewed in these past Trending Topics (from the U.K. and France), along with the new Canadian analyses, all have in common an agreement that UPFs have low overall nutritional quality and that the high UPF consumption is of concern. UPFs are often characterized as convenient and hyper-palatable with attractive packaging (1).
How Was ‘Ultra-Processed Foods’ Defined?
The reported food and drink data by survey participants in both 2005 and 2014 (1,2) was classified into four categories according to NOVA classification
, an internationally recognized system of classifying ingredients related to industrial food processing, based on a thesis presented by researchers at Brazil’s University of São Paolo over 10 years ago (3). Category 4, UPF, was the focus of the studies:
- Unprocessed or minimally processed foods including fresh, frozen or dry fruit, vegetables, nuts, legumes and plain meats and milk
- Processed culinary ingredients including sugar, salt, butter and vegetables oils
- Processed foods like canned fruits and vegetables, artisanal breads and cheeses
- Ultra-processed foods (UPFs) including industrial breads, reconstituted meat products, commercial and soft drinks, confectionary, commercial baked goods, crackers and other salty snacks, sauces, spreads and salad dressings and fast-food and frozen dishes.
What Did the CCHS Analyses Find?
The good news is that some UPF types, particularly beverages, declined between 2004 and 2015 (1). That said, the overall share of UPFs (including soft drinks) in Canada remained high in 2015 and contributed 46% of total daily energy for the overall population (as compared to 48% in 2004) with the highest for children and adolescents at 50% in 2015 (1,2). The high levels of UPF intake estimated in this study (1) are in line with previously reported estimates based on population-representative nutrition data from Canada and other high income nations (42% of total energy intake in Australia to about 57% in the United Kingdom) (1). For adults aged 55 or older, the intake of UPFs shifted upwards from about 42% of total usual energy in 2004 to 45% in 2015 (1). High UPF consumption was associated with less formal education, living in rural areas, people born in Canada and with Indigenous identity (2).
The researchers estimated the association between UPF consumption and morbidities (both self-reported) using multivariable logistic regression models on the 2015 data. They found that Canadian adults consuming the highest amounts of UPFs as a proportion of their energy intake had (2):
- 31% higher odds of obesity
- 37% higher odds of diabetes
- 60% higher odds of high blood pressure, compared to those consuming the least amount.
(Note: making conclusions about causal relationships from cross-sectional analyses should be done with caution.)
What Should Happen Next?
As practitioners, we should continue to promote national healthy eating guideline
recommendations to limit the consumption of highly processed foods and drinks. Repeat analysis of UPF intake over time could also help to inform polices targeting the food environment, such as access to UPFs in publicly funded spaces, labelling and taxation initiatives to guide consumer choice. These analyses can also be used to target public health consumer messaging and media literacy components within nutrition-related programs. Continued research on the associations between UPF intake and risk of morbidities is also needed to better understand whether these relationships are causal and if so how health related behaviours could be modified.
See Additional Content:
- Polsky JY, Moubarac JC, Garriguet D. Consumption of ultra-processed foods in Canada. Health Rep. 2020 Nov 18;31(11):3-15. doi: 10.25318/82-003-x202001100001-eng. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/33205938/
- Nardocci M, Polsky J, Moubarac JC. How ultra-processed foods affect health in Canada. Report prepared for Heart and Stroke. Montréal: TRANSNUT, Department of Nutrition, University of Montreal; June 2019. Available from: https://www.heartandstroke.ca/-/media/pdf-files/canada/media-centre/hs-moubarc-study-june-27-2019.ashx?rev=8ac040d6d03a41209fc6d8353ed325b3&hash=81A02F9268388596BD7089AA9C22419D
- Monteiro CA. Nutrition and health. The issue is not food, nor nutrients, so much as processing. Public Health Nutr. 2009;12(5):729–31. Available from: https://pubmed.ncbi.nlm.nih.gov/19366466/
Could Eating Cabbage and Fermented Vegetables Reduce Severe Outcomes of COVID-19?
During the COVID-19 pandemic you may be getting questions from your clients about how food and nutrients may help prevent or treat the coronavirus. The following analysis by a dietetic student looks at a study in adults related to eating fermented vegetables.
A recent narrative review compared COVID-19 mortality rates between and within countries, with a nutrition lens (1). This review led the authors to hypothesize that the severity of COVID-19 outcomes may be reduced through the consumption of foods such as cabbage and fermented vegetables.
A review of two ecological studies (2,3) suggested that there was a statistically significant association between a higher consumption of cabbage, cucumber and fermented vegetables and lower COVID-19 mortality rates. While there are notable limitations to ecological research (further discussed below), it is biologically plausible that cabbage and fermented vegetables could have a protective role on COVID-19 outcomes. The sulforaphane precursors found in cabbage and the Lactobacillus found in fermented vegetables both activate the nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a regulator of cellular anti-oxidative response (4-6). Nrf2 has been shown to protect against many of the factors that increase the risk of severe COVID-19 outcomes, including insulin resistance, inflammation and endothelial damage (7,8). Microbiome changes of the gut resulting from live bacterial cultures in fermented vegetables might also provide protective measures against COVID-19, although further studies are needed to prove whether this is the case (9,10).
A few limitations must be considered when analyzing this article. First, the authors did not perform a robust systematic review with risk of bias assessments, given the lack of original research on the topic. Additionally, the hypothesis of this review relied heavily on data from two ecological studies (2,3), making ecological fallacy a concern. While data compiled through ecological studies can be useful in showing possible associations between variables, results may be misinterpreted for a number of reasons. Most notably, data used for ecological studies comes from populations, rather than individuals, and as such, may have been impacted by a large number of possible confounding factors. For example, COVID-19 mortality rates could be confounded by location-specific factors such as the pandemic policies in place within each country (11), proportion of frontline workers (12) or levels of chronic disease within the population (13). Furthermore, the two ecological studies (2,3) supporting the hypothesis are preprints and therefore have not yet undergone peer review.
The authors acknowledged that this review was intended to generate hypotheses for future studies. Further research is needed to determine if the consumption of cabbage, cucumber and fermented foods can reduce the severity of outcomes resulting from COVID-19.
Written by Amber Foster, BSc. Reviewed by Justine Horne, PhD, RD and Tanis Fenton, PhD, RD, FDC.
- Bousquet J, Anto JM, Czarlewski W, Haahtela T, Fonseca SC, Iaccarino G, et al. Cabbage and fermented vegetables: from death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID‐19. Allergy. 2020 [Epub ahead of print] doi.org/10.1111/all.14549. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32762135/
- Fonseca S, Rivas I, Romaguera D, Quijal M, Czarlewski W, Vidal A, et al. Association between consumption of fermented vegetables and COVID‐19 mortality at a country level in Europe. medRxiv. 2020. doi.org/10.1101/2020.07.06.20147025. Abstract available from: https://www.medrxiv.org/content/10.1101/2020.07.06.20147025v1
- Fonseca SC, Rivas I, Romaguera D, Quijal-Zamorano M, Czarlewski W, Vidal A, et al. Association between consumption of vegetables and COVID‐19 mortality at a country level in Europe. medRxiv. 2020. doi.org/10.1101/2020.07.17.20155846. Available from: https://www.medrxiv.org/content/10.1101/2020.07.17.20155846v1
- Luang‐In V, Deeseenthum S, Udomwong P, Saengha W, Gregori M. Formation of sulforaphane and iberin products from thai cabbage fermented by myrosinase ‐ positive bacteria. Molecules. 2018;23(4):955. doi: 10.3390/molecules2304095. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/29671807/
- Yang L, Palliyaguru DL, Kensler TW. Frugal chemoprevention: targeting Nrf2 with foods rich in sulforaphane. Semin Oncol. 2016;43(1):146‐53. doi: 10.1053/j.seminoncol.2015.09.013. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/26970133/
- Senger DR, Li D, Jaminet SC, Cao S. Activation of the Nrf2 Cell defense pathway by ancient foods: disease prevention by important molecules and microbes lost from the modern western diet. PLoS One. 2016;11:e0148042. doi: 10.1371/journal.pone.0148042. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/26885667/
- Chen B, Lu Y, Chen Y, Cheng J. The role of Nrf2 in oxidative stress‐induced endothelial injuries. J Endocrinol. 2015;225(3):R83‐99. doi: 10.1530/JOE-14-0662. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/25918130/
- Xu L, Nagata N, Ota T. Glucoraphanin: a broccoli sprout extract that ameliorates obesity‐induced inflammation and insulin resistance. Adipocyte. 2018;7(3):218‐25. doi:10.1080/21623945.2018.1474669. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/29898626/
- Saad MJ, Santos A, Prada PO. Linking gut microbiota and inflammation to obesity and insulin resistance. Physiology. 2016;31(4):283‐293. doi: 10.1152/physiol.00041.2015. Available from: https://pubmed.ncbi.nlm.nih.gov/27252163/
- Zuo T, Zhang F, Lui GCY, Yeoh YK, Li AYL, Zhan H, et al. Alterations in gut microbiota of patients with COVID‐19 during time of hospitalization. Gastroenterology. 2020;159(3):944-55.e8. doi: 10.1053/j.gastro.2020.05.048. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32442562/
- Roser M, Ritchie H, Ortiz-Ospina E, Hasell, J. Policy responses to the coronavirus pandemic. Our World in Data: Oxford (UK): 2020. Available from: https://ourworldindata.org/policy-responses-covid
- Nguyen LH, Drew DA, Graham MS, Joshi, AD, Chuan-Gou G, Ma W, et al. Risk of COVID-19 among front-line health-care workers and the general community: a prospective cohort study. Lancet. 2020 Sep;5(9):475-43. doi: 10.1016/S2468-2667(20)30164-X. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32745512/
- Sanyaolu A, Okorie C, Marinkovic A, Patidar R, Younis K, Desai P, et al. Comorbidity and its impact on patients with COVID-19. SN Compr Clin Med. 2020 Jun:1-8. doi: 10.1007/s42399-020-00363-4. Epub ahead of print. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32838147/
Should I Recommend Vitamin D Supplements to Protect Against COVID-19? Updated November 2020
The Bottom Line:
- No studies have examined the effect of vitamin D to prevent or treat COVID-19 infections.
- Information extrapolated from randomized trials that examined respiratory tract infection prevention have not reported consistent beneficial effects of vitamin D compared to placebo in adults or children.
- Potential risks that have been identified include a higher rate of repeat episodes of pneumonia.
- While observational studies suggest that lower serum vitamin D levels are associated with inflammatory response, lower serum vitamin D levels are associated with other factors and not only with inadequate vitamin D intake.
- Vitamin D is an essential nutrient and vitamin D supplementation is recommended in a number of countries for various ages during the life cycle for general health.
COVID-19 Lockdown Associated with Weight and Dietary Changes Among Adults with Obesity
You may have heard from your clients that the pandemic lockdown has resulted in individuals feeling challenged to manage their weight. The following analysis by a dietetic student looks at a related study in adults with obesity.
In an observational study, researchers evaluated changes in weight and dietary habits among outpatients of a Northern Italian Obesity Unit after one month of a COVID-19 enforced lockdown (1). The participants (n=150), who were enrolled in a 12-month weight loss program, completed a 12-question multiple choice questionnaire. They also self-reported their weight after one month of lockdown, which was compared to a measured weight from before the lockdown period. On average, weight and BMI increased significantly (P<0.05) by 1.51 kg (3.3 lbs) and 0.58 kg/m2, respectively, during the first month of lockdown. Self-reported anxiety/depression was the strongest predictor of weight gain among the participants. Lower physical activity, boredom/solitude, enhanced eating, unhealthy eating and a lower level of education were also significantly associated with increased weight and BMI. The authors suggested that the adverse mental health effects of quarantine could be a major factor in the lifestyle changes of the participants (1), citing Ryan et al. that individuals with obesity are more likely to experience social isolation and depression (2).
There are several reasons why this study’s findings are low quality. A validated questionnaire was not used for this study and data, including follow-up weight, was self-reported. In addition, due to the nature of the study design, causation about the impact of the COVID-19 lockdown on weight and nutritional changes cannot be inferred. Moreover, generalizability of the results is limited to European adults with obesity who were participating in weight-loss counselling.
This low quality data suggests that individuals with obesity experienced weight gain during the first month of COVID-19 lockdown (1). Also in this study, self-reported anxiety/depression, lower levels of education, lower levels of exercise, higher levels of boredom/solitude, increased food consumption and the consumption of “unhealthy” foods were associated with weight gain. Further research is needed before weight-related COVID-19 clinical practice recommendations can be made.
Written by Laura Michailidis, BA Candidate. Reviewed by Justine Horne, PhD, RD and Tanis Fenton, PhD, RD, FDC.
- Pellegrini M, Ponzo V, Rosato R, Scumaci E, Goitre I, Benso A, et al. Changes in weight and nutritional habits in adults with obesity during the “lockdown” period caused by the COVID-19 virus emergency. Nutrients. 2020 Jul;12(7):2016. doi.org/10.3390/nu12072016. Abstract available from: https://pubmed.ncbi.nlm.nih.gov/32645970
- Ryan DH, Ravussin E, Heymsfield S. COVID 19 and the patient with obesity – the editors speak out. Obesity. 2020 Apr;28(5):847. doi.org/10.1002/oby.22808. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7228389
Food and Food Packaging and Coronavirus Risk
A recent opinion on SARS-CoV-2 and its Relationship to Food Safety
from the International Commission on Microbiological Specifications for Foods and government guidelines report that evidence does not support the concern that food and/or food packaging presents a risk of catching the coronavirus
Key Points and Practice Recommendations
- COVID-19 is a respiratory disease that spreads from person to person. It is not a foodborne or food packaging transmitted disease.
- Currently, no evidence supports that food, swallowing food or handling food packaging is a likely source or route of transmission of the virus.
- Coronaviruses are killed by common cleaning and disinfection methods and by cooking food to safe internal temperatures.
- Continue to follow good hand hygiene practices, social distancing and food safety precautions while food shopping and before preparing or eating food.
Country-Specific Food Safety Guidelines
Additional Information on Food, Food Safety and COVID-19
COVID-19 Trials and Research We Are Watching
The Herbal Medicine for the Treatment of Coronavirus Disease 2019 (COVID-19): A Systematic Review and Meta-Analysis of Randomized Controlled Trials evaluated the effectiveness and adverse events of oral herbal medicines (Chinese patent medicine: Lianhua Qingke granules, Shufeng Jiedu capsule, Jinhua Qinggan granules, Toujie Quwen granules) and herbal decoction when they were combined with Western medicines (Lopinavir/ritonavir, Arbidol Hydrochloride tablets, Chloroquine Phosphate tablets, Ambroxol Hydrochloride tablets, Moxifloxacin tablets, Interferon-alfa injections and Ribavirin injections) for the treatment of COVID-19 (seven RCTS; 855 patients from mainland China). While some significant effects of the combined therapy were found compared to Western medicine alone, poor reporting within the primary studies made it difficult to evaluate their quality and many of the outcomes had high heterogeneity (I2≥70%). More high quality RCTs are needed to further validate their effectiveness.
Vitamin D Trial
The COVIDENCE UK Study is investigating how diet and lifestyle factors might influence the transmission of SARS-CoV-2, severity of COVID-19 symptoms, speed of recovery and any long-term effects. The researchers aim to recruit at least 12,000 people and to obtain interim results by this summer.
Vitamin C Trials
A review from the Cochrane Library on Vitamin C Supplementation for Prevention and Treatment of Pneumonia of seven studies (five RCTs and two quasi-RCTs) involving a total of 2,774 participants (five studies in children and two studies in adults). The authors concluded that evidence was insufficient to determine an effect of vitamin C because of the very low quality evidence. Other good quality studies are needed to assess the role of vitamin C supplements for pneumonia prevention and treatment.
A randomized control trial published in JAMA in January 2020 showing a lack of effectiveness of intravenous vitamin C, hydrocortisone and thiamine as compared to hydrocortisone alone in a quicker resolution of septic shock suggests that intravenous vitamin C is not likely to be effective for COVID-19 treatment.
Several clinical trials examining the effect of vitamin C supplementation (both intravenous and oral) on COVID-19 treatment and prevention from around the world have been registered with the U.S. National Library of Medicine's ClinicalTrials.gov database. Two specific trials are:
- A trial from Wuhan designed to provide more definitive answers about the effectiveness of intravenous vitamin C for the treatment of severe 2019-nCoV infected pneumonia is underway with an expected completion date of September 2020. This trial is designed to provide more definitive answers about the effectiveness of intravenous vitamin C for COVID-19.
- The LOVIT (Lessening Organ Dysfunction with VITamin C ) trial is a multi-centre trial currently being conducted in Canada and with recent approval in a number of other countries as well. It aims to find out if intravenous vitamin C in high doses can improve health outcomes, particularly mortality, in septic COVID-19 patients.
A New Site - LitCOVID
LitCOVID is new from PUBMED. It is a site to help scientists keep track of COVID-19 evidence publications.
*Word of Caution from PEN Evidence Analysts: Please keep in mind that these papers are being rushed to publication as the information is wanted as soon as possible. Some of these papers are not peer reviewed. Peer reviewing is not a perfect process but it does allow an unbiased scrutiny of the work by someone external to the research group and is known to lead to better quality work. See additional information from the Canadian Broadcasting Corporation (CBC): Scientists Cut Peer-Review Corners under Pressure of COVID-19 Pandemic.
COVID-19 Trials and Research We Are Watching
Vitamin C Trials
A randomized control trial published in JAMA showing a lack of effectiveness of intravenous vitamin C, hydrocortisone and thiamine as compared to hydrocortisone alone in a quicker resolution of septic shock suggests that intravenous vitamin C is not likely to be effective for COVID-19 treatment.
A trial from the US National Library of Medicine ClinicalTrials.gov: Vitamin C Infusion for the Treatment of Severe 2019-nCoV Infected Pneumonia is underway (estimated completion September 2020). This trial is designed to provide more definitive answers about the effectiveness of intravenous vitamin C for COVID-19.
A New Site - LitCOVID
LitCOVID is new from PUBMED. It is a site to help scientists keep track of COVID-19 evidence publications.
*Word of Caution from PEN Evidence Analysts: Please keep in mind that these papers are being rushed to publication as the information is wanted ASAP. Some of these papers are not peer reviewed. While peer review is not a perfect process by any means, it does allow an unbiased review of the work by someone external to the research group.
Ultra-processed Foods and Early Death
Researchers continue to explore the relationship between the foods we eat and health outcomes. The British Medical Journal (BMJ) recently published two articles on the health effects associated with the consumption of ultra-processed foods and early death:
The National Health Service (NHS) in the U.K. has provided this analysis of the research, which notes the challenges of cohort studies, including the inability to prove cause and effect, the importance of potential confounding factors with observational research, and the difficulty of defining ultra-processed foods. People who frequently eat ulta-processed foods are different in several ways including income, physical activity and smoking habits, from people who eat foods prepared from scratch (1); it is not possible in studies such as these to fully control for these differences. Thus, it is cannot be assumed that the ultra-processed foods actually caused the cardiovascular disease or early deaths or that other aspects of their lifestyle were more important.
In addition, see the February 2019 PEN Trending Topic: The Association Between Ultraprocessed Food Consumption and the Risk of Mortality – What is the Real Deal?
- Schnabel L, Kesse-Guyot E, Allès B, Touvier M, Srour B, Hercberg S, et al. Association between ultraprocessed food consumption and risk of mortality among middle-aged adults in France. JAMA Intern Med. 2019 Feb 11. doi:10.1001/jamainternmed.2018.7289. [Epub ahead of print]. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/30742202
The Association Between Ultraprocessed Food Consumption and the Risk of Mortality – What is the Real Deal?
Originally Posted February 15, 2019. Reposted June 5, 2019
Another observational nutrition study is making headlines around the world (1-3) but is also raising concerns about the failure of news stories to address the significant limitations of the study. The observational prospective cohort study looked at the association between ultraprocessed food consumption and the risk of mortality in middle-aged adults in France (4). The authors concluded that an association existed based on the data of more than 44,000 participants.
A PEN Evidence Analyst offered this analysis:
The results portray a very weak relationship between ultraprocessed foods and mortality. The effect size, which was equal to a hazard ratio of 1.14, is so small that it is not likely of importance. GRADE guidelines encourage that for an observational study an effect size should be greater than 2, or better yet 5, before we should assume that there is an important effect (5). This hazard ratio of 1.14 was statistically significant, which is not surprising because there were over 44,000 participants in the study. When the sample size is very large, statistical significance is highly likely even when the effect is so small that it is not likely of any real importance.
Additional concerns are that the categorization of foods in the ultraprocessed category included sugar-sweetened beverages and highly processed snack foods but also included ready-made meals and breads, which could be quite nutritious. Further, the researchers allowed the participants to select which 24-hour periods they reported their food intake, so we don’t know how well their selections reflect typical intakes.
The results observed could be due to the fact that those that ate the most of these ultraprocessed foods were those most likely to have higher mortality rates for reasons beyond dietary intake. The individuals consuming the most of these ultraprocessed foods were more likely to be of lower income, smoke and/or be single obese males with low levels of physical activity. Some additional variable or variables related to these variables that were controlled for in the analysis could be the actual causal factor for mortality. Therefore, residual confounding may explain this study’s results.
The researchers did mention that reverse causation was possible; that is those people who are at higher risk of death from a chronic disease may have been selecting more processed foods. This type of study design cannot rule out reverse causation.
The NHS and Science Media Centre reviews also outline the limitations and put the study and its findings into perspective.
- Scutti S. Eating 'ultraprocessed' foods accelerates your risk of early death, study says. CNN. 2019 Feb 12. Available from: https://edition.cnn.com/2019/02/11/health/ultraprocessed-foods-early-death-study/index.html
- Eating ultra-processed foods can increase risk of early death: study. CTV. 2019 Feb 12. Available from: https://www.ctvnews.ca/health/eating-ultra-processed-foods-can-increase-risk-of-early-death-study-1.4293071
- Donnelly L. Modern diets could be killing us, suggests major study on ultra-processed foods. The Telegraph News. 2019 Feb 11. Available from: https://www.telegraph.co.uk/news/2019/02/11/modern-diets-could-killing-us-suggests-major-study-ultra-processed/
- Schnabel L, Kesse-Guyot E, Allès B, Touvier M, Srour B, Hercberg S, et al. Association between ultraprocessed food consumption and risk of mortality among middle-aged adults in France. JAMA Intern Med. 2019 Feb 11. doi:10.1001/jamainternmed.2018.7289. [Epub ahead of print]. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/30742202
- Guyatt GH, Oxman AD, Sultan S, Glasziou P, Akl EA, Alonso-Coello P, et al. GRADE guidelines: 9. Rating up the quality of evidence. J Clin Epidemiol. 2011 Dec;64(12):1311-6. doi: 10.1016/j.jclinepi.2011.06.004. Epub 2011 Jul 30. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=21802902