Dietitians Make A Difference

Dietitians Make a Difference in Chronic Disease Management

Compared to usual care, nutrition counselling from a dietitian (or international equivalent) probably improves the following outcomes:

• blood pressure (systolic and diastolic) in adults with chronic kidney disease who are not receiving dialysis
• weight outcomes (waist circumference, percent weight loss, BMI) in adults with overweight or obesity who are involved in short-term (<12 months) weight management interventions

• blood lipids (total cholesterol, LDL cholesterol, triglycerides) and blood pressure (systolic blood pressure) in adults with dyslipidemia
• blood pressure (systolic and diastolic) and quality of life in adults with overweight or obesity who are involved in weight management interventions
• glycemic control (A1C, fasting blood glucose), cholesterol levels, blood pressure and weight outcomes (weight, waist circumference, BMI) in adults with prediabetes
• urinary sodium excretion, in adults with chronic kidney disease who are not receiving dialysis

Compared to nutrition advice from other health professionals, nutrition counselling from a dietitian (or international equivalent) may improve glycemic control (A1C) and weight outcomes (weight, BMI) in adults with type 2 diabetes.

Dietitian involvement may improve weight and dietary intake in individuals with eating disorders when coupled with psychological treatment, compared to psychological treatment alone.

Dietitian involvement may not affect triglycerides or progression from prediabetes to type 2 diabetes (compared to usual care) or LDL cholesterol, systolic blood pressure or diastolic blood pressure (compared to nutrition advice from other health professionals) in adults with type 2 diabetes. Similarly, dietitian involvement may not affect fasting blood glucose in adults involved in short-term (<12 months) weight management interventions. 

All but one systematic review included internationally equivalent certifications in their definition of a dietitian. 

As with other weight management interventions, dietitian-delivered interventions have only been shown to reduce weight in the short term. 

See Additional Content:
What is the effectiveness of dietary interventions for preventing or treating chronic disease in the primary care setting?
What is the recommended weight gain in pregnancy?

To see the full practice question, including the Evidence Statements, Comments and References, click here.

Dietitians Make a Difference in Malnutrition

Members of the Collaborative Partnership including Dietitians of Canada, the British Dietetic Association and Dietitians Australia suggest dietary counselling plus oral nutrition supplements as needed for adults in hospital who are malnourished or at risk of malnutrition.

Conditional recommendation | Low quality evidence ⊕⊕oo

Dietitians are involved in providing dietary counselling with or without additional nutrition supplements as needed. The recommendation puts a high value on a small but important reduction in six-month mortality and complications and a possible decrease in six-month readmissions. Dietary counselling with or without nutrition supplements may also result in small but important improvements in nutrition status, nutrient intake and body weight. The studies included predominantly older adults in hospital at risk of malnutrition or diagnosed with malnutrition receiving dietary counselling with or without oral nutrition supplements compared to standard care providing no or minimal dietary counselling. Cost benefits have also been reported using dietary counselling plus oral nutrition supplements compared to standard care for treating malnutrition in hospitalized adults.  

The recommendation is conditional since there were no improvements in other clinical outcomes (i.e. 30-day mortality, length of hospital stay, quality of life and functional status) and because the quality of evidence was low for most outcomes due to varied interventions (e.g. dietary counselling alone, with required supplements or with supplements as needed) and studies with serious risk of bias.
 

See Additional Content:
What screening process can be used to identify adults at risk of malnutrition admitted to hospital?
What nutrition assessment process can be used to diagnose malnutrition in adults admitted to hospital?
Nutrition Support - Enteral and Parenteral Knowledge Pathway. 

Dietitians Make a Difference in Birth Outcomes

Involving a dietitian in prenatal care may decrease the incidence of low birth weight (LBW) and preterm birth. At this time, evidence suggests that dietitian involvement may not affect the incidence of macrosomia, large-for-gestational age (LGA) or infant mortality, although some outcomes had few studies or mixed results. There is no evidence about the effect of dietitian involvement (compared to no dietitian involvement) on the incidence of small-for-gestational age (SGA).

A 2023 systematic review of 14 studies (five RCTs, three retrospective cohort studies, two cross-sectional studies, two case-control studies, one implementation trial, one pilot study) concluded that dietitian involvement during pregnancy decreased the incidence of LBW (<2500 g) and preterm birth (<37 weeks gestation) compared to no dietitian involvement. The incidence of macrosomia (>4000 g), LGA (birth weight >90th percentile for gestational age) and infant mortality (stillbirth, neonatal death or perinatal death) were not found to be affected by dietitian involvement, although these outcomes were based on few studies or mixed results. No studies examined the effect of dietitian involvement compared to no dietitian involvement on SGA (birth weight <10th percentile for gestational age).

Grade of Evidence C

Successful intervention designs, as well as participant characteristics and reporting of intervention details, varied widely. All successful interventions included a nutrition counselling component, although it was not always clear whether group or individual counselling was provided. Frequent follow up (>2 sessions), especially in the later stages of pregnancy, was commonly reported in successful interventions.

To see the full practice question, including the Evidence Statements, Comments and References, click here.

Looking for more information on pregnancy? See the following knowledge pathways:
Pregnancy
Pregnancy - Hypertension
Pregnancy - Nausea and Vomiting/Hyperemesis Gravidarum
Pregnancy - Multi-fetal
Gestational Diabetes
Nutrition and Fertility.

Using Counselling Models in Dietetic Practice

The latest background to be updated on the PEN website is the Counselling Models Background. This background provides an overview of counselling models and theories that are applicable to dietetic practice, including nutrition counselling. 

This background is one of 91 PEN backgrounds, including the most recently published or updated:
Nutritional Genomics Background
Nervous System - Pediatric/Paediatric Epilepsy: Ketogenic Diet Background
Food, Nutrition and Eating Issues of Transgender and Gender-diverse Individuals Background
Diet Composition - Paleolithic Diet Background
COVID-19: Food, Nutrition and Health Background
Cannabis and Health Background
Diabetes - Glycemic Index Background
Food Safety Culture and Climate Background
Metabolic and Bariatric Surgery Background
Dysphagia Background
Nutritional Implications of Cancer Treatment Background - Mouth Changes Background
Weight-Inclusive Approach Background
Household Food Insecurity Background
Nutrition Assessment - Adult Background
Physiology of Body Weight, Weight Gain and Adipose Tissue Background

Thank you Canada's Nutrition Month 2024 Content Reviewers