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Trending Topics

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.

  • USDA Dietary Guidelines

    The 2020-2025 USDA Dietary Guidelines were released on December 29, 2020: https://health.gov/news/202012/usda-and-hhs-just-released-dietary-guidelines-americans-2020. While key recommendations to limit saturated fat, added sugars, sodium and alcohol remain the same, there is an additional emphasis on following a healthy dietary pattern at every life stage, including infants and toddlers. Guidelines are available at: https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf.  

    Posted: 2021-01-12

  • 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!

    Posted: 2021-01-11

  • Consumption of Ultra-Processed Foods Trending Down But Still High

    processed junk food french fries cola hamburgerUltra-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). 
     
    Sound Familiar? 
    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:
     
    1. Unprocessed or minimally processed foods including fresh, frozen or dry fruit, vegetables, nuts, legumes and plain meats and milk
    2. Processed culinary ingredients including sugar, salt, butter and vegetables oils
    3. Processed foods like canned fruits and vegetables, artisanal breads and cheeses 
    4. 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:
     
    References
    1. 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/ 
    2. 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 
    3. 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/     

    Posted: 2020-11-30

  • 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.  
     
    Analysis Details
    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.
     
    Bottom Line
    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.
     
    References
    1. 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/ 
    2. 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
    3. 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
    4. 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/ 
    5. 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/ 
    6. 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/ 
    7. 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/
    8. 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/ 
    9. 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/ 
    10. 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/ 
    11. 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
    12. 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/
    13. 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/ 

    Posted: 2020-11-17

  • Should I Recommend Vitamin D Supplements to Protect Against COVID-19? Updated November 2020

    The topic of vitamin D supplementation and COVID-19 remains in the news. We have reviewed the recent studies and our bottom line from May 2020 has not changed. There is currently not enough evidence to indicate that vitamin D supplements can prevent or improve the course of COVID-19. We have updated our evaluation of the evidence, see PEN Trending Topic Can Vitamin D Supplements Prevent or Improve the Course of COVID-19? May 2020. 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.   


    Posted: 2020-11-02

  • 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.

    Study Details
    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).

    Analysis
    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.
     
    Bottom Line
    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.
     
    References
    1. 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  
    2. 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   

    Posted: 2020-10-27

  • 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
     

    Posted: 2020-09-10

  • Canadian Clinical Practice Guidelines on Adult Obesity Released

    Obesity Canada and the Canadian Association of Bariatric Physicians and Surgeons have released new clinical practice guidelines for the management of adults with obesity. The intent of the guidelines is to improve the access and standard of care for individuals across all regions of Canada. The guidelines include recommendations for: reducing weight bias in obesity management, enabling participation in activities of daily living, physical activity, mental health, medical nutrition therapy, pharmacotherapy, behavioural interventions, bariatric surgery, primary care/primary health care, management in Indigenous Peoples, management in women in reproductive years and more. Health professionals are encouraged to ask clients for permission to discuss their weight, assess and advise on management, agree on client goals and assist with barriers and drivers. These new guidelines will be integrated into PEN Practice Questions and other related content over the coming months and can also be accessed at: International Weight/Obesity Guideline Collection (Children and Adults).

    Posted: 2020-08-11

  • Taxation of Salt and Foods High in Sodium

    A new systematic review (1) looking at the effectiveness and feasibility of taxing salt and foods high in sodium was highlighted in Salt in the News (June 2020) from World Action on Salt & Health.

    The systematic review included eighteen studies found between 2000 and 2019 (1). Fifteen of the studies reported on the effects of salt taxes: eight looked at taxing salt itself, foods high in salt and unhealthy foods (modelling studies, based on estimates of what the effects would be); four looked at the impact of salt taxation (real-world evaluation); two looked at price and subsides (experimental design/simulated online grocery stores); and one looked at cost-effectiveness of taxation (a review). Six of the 18 studies provided information relevant to country implementation of salt taxes and two of the 18 studies reported stakeholder perceptions toward salt taxation.

    The authors found that the actual practice of salt taxation is limited (1). Three of the four real-world evaluation studies, mostly gray literature, did not report a measure of uncertainty (e.g. 95%CI or SE) and the two simulation studies showed wide confidence intervals, raising questions about the precision of the study results. Relying mostly on the modelling studies and noting that the studies varied in magnitude and range of measures (making them difficult to compare and summarize), the authors provided the following key summary points:
    • There is some indication of potential effectiveness and cost-effectiveness of salt taxation.
    • Taxation of food can have unintended outcomes, such as the decreased consumption of healthy foods or an increased consumption of other unhealthy, untaxed substitutes.
    • When taxes for unhealthy foods were combined with subsidies towards heathy foods, the benefits were increased.
    • Taxing all foods based on their salt content (broader application) is likely to have more impact than taxing only specific products high in salt and minimizes opportunity for substitution for other high sodium foods.

    High salt diets (more than 5 g/day for adults (2)) are considered a leading dietary risk for death and disability globally (3). Continued research on population sodium reduction strategies (4) and other fiscal strategies, such as taxation, is needed to help reduce salt consumption.


    References
    1. Dodd R, Santos JA, Tan M, Campbell NR, Mhurchu CN, Cobb L, et al. Effectiveness and feasibility of taxing salt and foods high in sodium: a systematic review of the evidence. Adv Nutr. 2020 Jun 20;nmaa067.doi: 10.1093/advances/nmaa067. Available from: https://pubmed.ncbi.nlm.nih.gov/32561920/
    2. World Health Organization. WHO guideline: sodium intake for adults and children. Geneva, Switzerland: WHO Press; 2012. Available from: https://apps.who.int/iris/bitstream/handle/10665/77985/9789241504836_eng.pdf;sequence=1 
    3. GBD 2017 Diet Collaborators. Health effects of dietary risks in 195 countries, 1990-2017: a systematic analysis for the global burden of disease study 2017. Lancet. 2019;393(10184):1958-72. Available from: https://pubmed.ncbi.nlm.nih.gov/30954305/
    4. WHO. Global strategy on diet, physical activity and health. Population sodium reduction strategies. [cited 2020 Jul 23]. Available from:  https://www.who.int/dietphysicalactivity/reducingsalt/en/   

    Posted: 2020-07-27

  • COVID-19 Trials and Research We Are Watching

    Herbal Medicines  
    Completed  
    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 
    Ongoing
    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 
    Completed
    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. 

    Ongoing
    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.  

    Posted: 2020-06-10

  • SARS-CoV-2 Virus Stability and Disinfecting

    Two recent studies have emerged on the persistence of the coronavirus on various surfaces (1,2). Using an in vitro study, Van Doremalen et al. examined how long SARS-CoV-2 virus (i.e. the virus that causes COVID-19*) remained viable on four surfaces (cardboard, plastic, stainless steel and copper) for varying lengths of time (1). At room temperature and 40% humidity, viable SARS-CoV-2 viruses were detectable up to 24 hours on cardboard and up to 72 hours on stainless steel and plastic. The virus was not viable after four hours on copper. 

    Kampf et al. reported a review on coronavirus persistence on surfaces and materials (2). While this second study examined coronaviruses, it did not specifically study the SARS-CoV-2 virus; the authors suggest that they expect the persistence and inactivation of this new coronavirus are likely similar. They found that coronaviruses can remain potentially infectious from two hours up to nine days on various materials. At higher air temperatures of 30 to 40 °C, persistence was reduced compared to room temperatures. The studied viruses were stable (≥28 days) at refrigerator temperature, 4 °C. Humidity influenced persistence, as coronaviruses were less stable at 30% relative humidity compared to 50% relative humidity. The researchers also found that biocidal agents including 62-71% ethanol, 0.5% hydrogen peroxide or 0.2% sodium hypochlorite (bleach - preparation instructions below) used for disinfecting inactivated coronaviruses within one minute. Other biocidal agents were noted to be less effective.

    Various organizations have now recommended guidelines based on the results of the first study. These include: 

    • Wash your hands thoroughly with soap and water for 20 seconds before and after preparing and eating food, using the washroom, after sneezing or coughing (3). Although the risk is low, if you are concerned or if you or someone in the household is of high risk, wash your hands after handling anything that might be contaminated such as cardboard, plastic and stainless steel (4). 
    • Disinfect hard surfaces daily including high touch areas such door handles, light switches, counter tops, tables, keyboards, toys, phones and TV remotes using ER-approved disinfectant (3).
      • Refer to Health Canada’s Hard Surface Disinfectants and Hand Sanitizers (COVID-19) for instructions and for a list of effective disinfectants. Be sure to read manufacturers’ directions on the labels of the disinfectant cleaning product as many of these need to remain in contact with the surface for a period of time (e.g. 30 seconds) to be effective (e.g. do not just spray on and wipe off) (5). 
      • As these products are currently hard to find because of the COVID-19 pandemic, a solution of diluted bleach can also be used as per instructions on the label of the bleach container. For 5% sodium hypochlorite bleach (the usual concentration sold in stores) use 5 mL (1 tsp) per 250 mL (1 cup) of water or 20 mL (4 tsp) per 1 litre (4 cups) of water to make a 0.2% solution (5).
      • Cleaning products remove germs and dirt, lowering their numbers and reducing the risk of spreading infections (5). Products with disinfectants kill germs.

    *Note: SARS-CoV-2 is the name of the virus. COVID-19 is the disease the virus causes.

    References

    1. van Doremalen N, Bushmaker T, Morris DH, Holbrook MG, Gamble A, Williamson BN, et al. Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1. N Engl J Med. 2020 Mar 17. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=32182409
    2. Kampf G, Todt D, Pfaender S, Steinmann E. Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents. J Hosp Infect. 2020 Mar;104(3):246-51. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=32035997
    3. Health Canada. Coronavirus Disease (COVID-19): prevention and risks. 2020 Apr 1. Available from: https://www.canada.ca/en/public-health/services/diseases/2019-novel-coronavirus-infection/prevention-risks.html?topic=tilelink
    4. Harvard T.H. Chan. School of Public Health. Food Safety, nutrition, and wellness during COVID-19. 2020 Mar 25. Available from https://www.hsph.harvard.edu/nutritionsource/2020/03/25/food-safety-nutrition-and-wellness-during-covid-19/
    5. Health Canada. Hard surface disinfectants and hand sanitizers (COVID-19). 2020 Mar 30. Available from    https://www.canada.ca/en/health-canada/services/drugs-health-products/disinfectants/covid-19.html

    Posted: 2020-04-02

  • Immunity, Nutrition and COVID-19

    Have you been asked questions regarding the COVID-19 virus, immunity and nutrition? The following resources may help you answer them, see:

    The novel coronavirus is new and evidence to support specific dietetic recommendations is not yet available in the scientific literature. The bottom line is that a healthy diet rich in fruit and vegetables, protein foods and whole grains is important for a strong immune system as are other healthy lifestyle habits (e.g exercise, not smoking, adequate sleep, managing stress etc). There is no one food or nutrient, supplement or herb that will protect you from the COVID-19 virus. The WHO has stated that there is no evidence that the consumption of garlic will prevent COVID-19. For this and other myth busters see WHO's advice for the public: myth busters. For more information about how to protect yourself and others, please follow the advice of your health authorities. 

    Posted: 2020-04-01

  • New Study - Dairy and Breast Cancer Risk

    Many news websites, including CTV (1), reported on a study (2) that looked at soy and dairy consumption and breast cancer risk. The study, which is part of the Adventist Health Study-2 (3), followed 52,795 North American women (mean age 57.1 years; free of cancer at study onset) for 7.9 years (between 2002 to 2007) who had a high average soy consumption. Self-reported food frequency questionnaires and 24-hour recalls were used to assess dietary intakes at entry into the study. 

    There were 1,057 new breast cancer cases found via North American cancer registries during the study time (2). Intakes of dairy calories and dairy milk were associated with a slightly greater risk of breast cancer independent of soy intake (hazard ratio (HR) 1.22; 95% confidence interval (CI), 1.05 to 1.40 and HR 1.50; 95%CI, 1.22 to1.84, respectively, comparing 90th to 10th percentiles of intakes), while there were no clear associations found between soy products and breast cancer. Fat level of milks and the consumption of cheese and yogurt showed no associations with cancer. A decreased risk of breast cancer was associated when substituting median intakes of soy milk for dairy milk (HR, 0.68; 95%CI, 0.55 to 0.85). The authors concluded that as milk intake increased, so did the risk of breast cancer, when adjusted for soy intake.

    An important concern about this study is that the news headline stated “One cup of milk per day associated with up to 50 per cent increase in breast cancer risk: study” (1), which is misleading since it focused on the relative risks of a rare outcome. Looking at the absolute risks (which is a better way to report these results since the cancer was rare), the risk of cancer in this study was 2% (2 cases per 100 women) and 3% (3 cases per 100 women) among women who drank milk (HR=1.50). The absolute risk difference is 1%, so the headline stating 50% increase is reporting a statistic that suggests a big risk. Reporting the absolute risk difference (1%) gives more relevant information on the actual risk for an individual (4).

    When analyzing this study there are a few limitations that should be considered. This is an observational study, so cause and effect cannot be established. Dietary intakes were self-reported and only measured once at baseline, so there is room for errors and omissions. The study did not adjust for social determinants of health or quantities of moderate or total physical activity, quantity of alcohol consumed or amounts smoked (the authors only controlled for vigorous activity, duration of alcohol use and smoking ever or never), so some or all of these variables could confound the results. 

    These results contrast with findings reported by the American Institute for Cancer Research (5) and an overview of systematic reviews (6), which found no consistent associations between dairy products or milk intake and the risk of postmenopausal breast cancer and actually observed a reduced risk of premenopausal breast cancer. 

    Bottom Line
    The authors of the study comment that dairy milk does have positive nutritional qualities and suggest that more research is needed to understand whether there is a true link between dairy intake, or other closely-related unidentified factor(s), and breast cancer risk. Until further research is available, dietitians can continue to review healthy lifestyle behaviours with clients including eating a balanced and varied diet that includes lots of vegetables, fruit and whole grain foods; engaging in regular physical activity; and avoiding smoking. Refer to the PEN client handout: Cancer Prevention Eating Guidelines. 

    References

    1. Bogart N. One cup of milk per day associated with up to 50 percent increase in breast cancer risk: study. CTV News. February 25, 2020. [cited 2020 Feb 27]. Available from: https://www.ctvnews.ca/health/one-cup-of-milk-per-day-associated-with-up-to-50-per-cent-increase-in-breast-cancer-risk-study-1.4826979
    2. Fraser GE, Jaceldo-Sielg K, Orlich M, Mashak A, Sirirat R, Knutsen S. Dairy, soy, and risk of breast cancer: those confounded milks. Int J Epidemiol. 2020 Feb; pii: dyaa007. doi: 10.1093/ije/dyaa007. Available from: https://www.ncbi.nlm.nih.gov/pubmed/32095830
    3. Loma Linda University Health. Adventist Health Study-2. 2020. [cited 2020 Feb 27]. Available from: https://adventisthealthstudy.org/
    4. Noordzij M, van Diepen M, Caskey FC, Jager JK. Relative risk versus absolute risk: one cannot be interpreted without the other. Nephrol Dial Transplant. 2017 Apr;32(suppl 2): :ii13-ii18. doi: 10.1093/ndt/gfw465. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=28339913
    5. American Institute for Cancer Research. Key findings. Diet, nutrition, physical activity and breast cancer. Revised 2018. Available from: https://www.aicr.org/research/the-continuous-update-project/breast-cancer/
    6. Jeyaraman M, Abou-Setta, Grane L, Farshidfar F, Copstein L, et al. Dairy product consumption and development of cancer: an overview of reviews. BMJ Open. 2019 Jan;9(1):e023625. doi: 10.1136/bmjopen-2018-023625. Available from:   https://www.ncbi.nlm.nih.gov/pubmed/30782711

    Posted: 2020-02-27

  • Addressing Stigma: Towards a More Inclusive Health System

    The Chief Public Health Officer’s Report on the State of Public Health in Canada in 2019 includes information about trends and the need to provide trusted, evidence-based information to Canadians. The report  summarizes Canadian health status in terms of mental illness, substance use, tuberculosis, HIV, obesity, vaccine coverage, sexually transmitted infections, youth vaping, youth cigarette smoking and the opioid crisis. The report also addresses stigma that affects health including stigma experienced by First Nations, Inuit, and Métis peoples, African, Caribbean and Black Canadians, seniors and members of the LGBTQ2+ people. 

    The report was developed based on stakeholder engagement and evidence reviews conducted of social and health science databases. Interviews and discussions involved >90 leaders from across Canada, which included individuals with lived experience, policy-makers, researchers, clinicians and administrators. It presents a new Action Framework for Building an Inclusive Health System to explore how stigma can be addressed.  

    See Additional Content: Weight Stigma Background.

    Posted: 2020-02-25

  • Vitamin D Update: Supplementation and Pregnancy and Perinatal Outcomes and 25-hyroxy-vitamin D as a Marker for Nutrient Deficiency and Sufficiency

    Vitamin D has been a very active area of research in recent decades. Not only have there been numerous research studies published, there have also been numerous systematic reviews published summarizing these studies. Recently, researchers in Alberta, Canada undertook a systematic review of the systematic reviews that investigated the importance of vitamin D in pregnancy for important perinatal and infant outcomes (1).

    This systematic review of systematic reviews found 42 systematic reviews of 204 primary studies that evaluated either vitamin D supplementation in pregnant women and/or examined the association between serum vitamin D levels for at least one predefined perinatal outcome (1). The researchers evaluated the systematic reviews for research quality using the AMSTAR tool and only analyzed data from the 13 systematic reviews with high AMSTAR scores. 

    The systematic reviews of randomized controlled trials (RCTs) with the highest quality of evidence showed no benefits from vitamin D supplementation regarding preterm birth, preeclampsia, gestational diabetes, stillbirth, low birth weight or caesarean section (1). A significant difference was found for small-for-gestational age; however, this evidence was low quality for two reasons: 1) the high risks of bias in the included studies without an accompanying sensitivity analysis to examine the low risk of bias studies separately, and 2) imprecision due to the small numbers of small-for-gestational age births in the included studies. Systematic reviews of observational studies showed that women with low 25-hyroxy-vitamin D levels had higher rates of preterm birth, preeclampsia, gestational diabetes and small-for-gestational age. 

    The findings of this systematic review (1) reinforce the findings of a 2017 systematic review (2) that found that the superior health of people with higher vitamin D serum levels suggested by the frequent associations observed in observational studies are not seen in randomized trials of vitamin D supplementation. Additionally, there is increasing evidence that serum 25-hyroxy-vitamin D, the vitamin D status marker, is a negative acute phase reactant, which decreases in response to other variables (2-9). Specifically, researchers have observed that 25-hyroxy-vitamin D decreases in response to inflammation (3), acute illness (4), ill health (2), critical illness (5), surgery (6,7) and when C-reactive protein increases (3,7-9). If a marker changes in response to other variables, then it has limited use as a nutritional adequacy marker.

    References

    1. Bialy L, Fenton T, Shulhan-Kilroy J, Johnson DW, McNeil DA, Hartling L. Vitamin D supplementation to improve pregnancy and perinatal outcomes: an overview of 42 systematic reviews. BMJ Open. 2020 Jan 20;10(1):e032626. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/31964667
    2. Autier P, Mullie P, Macacu A, Dragomir M, Boniol M, Coppens K, et al. Effect of vitamin D supplementation on non-skeletal disorders: a systematic review of meta-analyses and randomised trials. Lancet Diabetes Endocrinol. 2017 Dec;5(12):986-1004. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/29102433
    3. McMillan DC, Maguire D, Talwar D. Relationship between nutritional status and the systemic inflammatory response: micronutrients. Proc Nutr Soc. 2019 Feb;78(1):56-67. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/30220267
    4. Kostoglou-Athanassiou I, Pantazi E, Kontogiannis S, Kousouris D, Mavropoulos I, Athanassiou P. Vitamin D in acutely ill patients. J Int Med Res. 2018 Oct;46(10):4246-57. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/30157690
    5. Czarnik T, Czarnik A, Gawda R, Gawor M, Piwoda M, Marszalski M, et al. Vitamin D kinetics in the acute phase of critical illness: a prospective observational study. J Crit Care. 2018 Feb;43:294-9. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/28968524
    6. Binkley N, Coursin D, Krueger D, Iglar P, Heiner J, Illgen R, et al. Surgery alters parameters of vitamin D status and other laboratory results. Osteoporos Int. 2017 Mar;28(3):1013-20. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/27826645
    7. Waldron JL, Ashby HL, Cornes MP, Bechervaise J, Razavi C, Thomas OL, et al. Vitamin D: a negative acute phase reactant. J Clin Pathol. 2013 Jul;66(7):620-2. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=23454726
    8. Kruit A, Zanen P. The association between vitamin D and C-reactive protein levels in patients with inflammatory and non-inflammatory diseases. Clin Biochem. 2016 May;49(7-8):534-7. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/?term=26778547
    9. Silva MC, Furlanetto TW. Does serum 25-hydroxyvitamin D decrease during acute-phase response? A systematic review. Nutr Res. 2015 Feb;35(2):91-6. Abstract available from:      https://www.ncbi.nlm.nih.gov/pubmed/?term=25631715

    Posted: 2020-02-07

  • Can Selenium-rich Lentils Reduce Arsenic Toxicity in Chronically-Exposed Individuals?

    New research examined the use of selenium-rich lentils as a method to reduce arsenic toxicity and arsenic levels in biological samples, and to improve health indicators in those with chronic exposure to arsenic from water and food. 

    A double-blind, cluster-randomized, placebo-controlled trial of 405 healthy Bangladesh people (14 to 75 years of age) with chronic exposure to arsenic was conducted (1). The intervention group (204 participants) was provided with 65 gm of selenium-rich lentils containing 55 μg selenium/day and the control group (201 participants) were provided with the same amount of lentils but of with low selenium levels (1.5 ug selenium/day). At baseline, three and six months, total arsenic levels were measured from urine, stool and blood samples and anthropometric measurements were taken. Hair samples were also taken at baseline and at six months follow up. Participants who consumed the selenium-rich lentils were found to be excreting more arsenic in their urine (measured as arsenic metabolite (dimethylasrsinic acid)) at six months compared to the control group (P=0.008). Some health indicators, including the incidence of allergy (P=0.02) and asthma (P=0.05), were lower in the intervention group compared to the control group, and body mass index was higher (P<0.01) (the participants’ average BMI was 22). The authors suggested that selenium-rich lentils can increase arsenic excretion and improve the health indicators among people with high arsenic exposure. They recommended longer term larger scale studies be conducted to verify these results and to examine if higher concentrations of selenium would provide additional health benefits. 


    For additional information on the potential health effects of consuming arsenic, see the following PEN Content:
    Is the consumption of rice (white and brown) associated with increased arsenic-related health risks?
    Food Safety - Arsenic in Rice Background
    Trending Topic - Do New Parents or Parents-to-be Need to be Concerned with Dietary Arsenic Exposure?

    References

    1. Smits JE, Krohn RM, Akhtar E, Hore SK, Yunus M, Vandenberg A, et al. Food as medicine: selenium enriched lentils offer relief against chronic arsenic poisoning in Bangladesh. Environ Res. 2019 Sept;176:108561. Abstract available from: https://www.ncbi.nlm.nih.gov/pubmed/31299617

    Posted: 2020-01-20

  • Food Trends in 2020

    Registered dietitians, chefs and the food industry weigh in on expected food trends for the coming year. Common themes are an expected growth in the number of CBD-infused beverages and food products (particularly in Britain and Canada), more plant-based foods and alternative meat options, growing number of 'flexitarians' (those who follow a minimally plant-based diet) and considerations given to sustainable choices. Check out a few of our favourite predictions:

    Happy New Year! 

    Posted: 2020-01-03

  • 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?

    References:

    1. 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   

    Posted: 2019-06-06

  • 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.  

    References:

    1. 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
    2. 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
    3. 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/
    4. 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
    5. 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

    Posted: 2019-06-05

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