Recommendations Summary

AWM: Dietary Approaches for Caloric Reduction 2014

Click here to see the explanation of recommendation ratings (Strong, Fair, Weak, Consensus, Insufficient Evidence) and labels (Imperative or Conditional). To see more detail on the evidence from which the following recommendations were drawn, use the hyperlinks in the Supporting Evidence Section below.


  • Recommendation(s)

    AWM: Dietary Approaches for Caloric Reduction in Weight Loss

    For weight loss, the registered dietitian nutritionist (RDN) should advise overweight or obese adults that as long as the target reduction in calorie level is achieved, many different dietary approaches are effective. There is strong and consistent evidence that when calorie intake is controlled, macronutrient proportion, glycemic index and glycemic load of the diet are not related to losing weight.

    Rating: Strong
    Imperative

    AWM: Dietary Approaches for Caloric Reduction in Weight Maintenance

    For weight maintenance, the registered dietitian nutritionist (RDN) should advise overweight and obese adults that as long as the target reduction in calorie level is achieved, many different dietary approaches are effective. A moderate body of evidence provides no data to suggest that any one macronutrient is more effective than any other for avoiding weight re-gain in weight-reduced persons. Strong and consistent evidence shows that glycemic index and glycemic load are not associated with body weight and do not lead to better weight maintenance.

    Rating: Strong
    Imperative

    • Risks/Harms of Implementing This Recommendation

      None.

    • Conditions of Application

      Several dietary approaches were shown to be effective for weight loss, however the nutrient adequacy of these diets was not evaluated:

      • Dietary patterns that are low in dietary energy density
      • Dietary Reference Intakes (DRI): 20% to 35% of calories from fat, 45% to 65% of calories from carbohydrate and 10% to 35% of calories from protein
      • European Association for the Study of Diabetes Guidelines, which focuses on targeting food groups, rather than the formal prescribed energy restriction while still achieving an energy deficit
      • Higher protein: 25% of total calories from protein, 30% of total calories from fat, 45% of total calories from carbohydrate; with provision of foods that realized energy deficit
      • Higher protein ZoneTM-type diet (five meals per day, each with 40% of total calories from carbohydrate, 30% of total calories from protein, 30% of total calories from fat) without formal prescribed energy restriction but realized energy deficit
      • Ovolactovegetarian-style diet with prescribed energy restriction
      • Low-calorie diet with prescribed energy restriction
      • Low-carbohydrate (initially less than 20g per day carbohydrate) diet without formal prescribed energy restriction but realized energy deficit
      • Low-fat (10% to 25% of total calories from fat) vegan style diet without formal prescribed energy restriction but realized energy deficit
      • Low-fat (20% of total calories from fat) diet without formal prescribed energy restriction but realized energy deficit
      • Low-glycemic load diet, either with formal prescribed energy restriction or without formal prescribed energy prescription but with realized energy deficit
      • Lower fat (less than 30% fat), high dairy (four servings per day) diets with or without increased fiber and low-glycemic index or load foods (low-glycemic load) with prescribed energy restriction
      • Macronutrient-targeted diets (15% or 25% of total calories from protein; 20% or 40% of total calories from fat; 35%, 45%, 55% or 65% of total calories from carbohydrate) with prescribed energy restriction
      • Mediterranean-style diet with prescribed energy restriction
      • Moderate protein (12% of total calories from protein, 58% of total calories from carbohydrate, 30% of total calories from fat) with provision of foods that realized energy deficit
      • Provision of high-glycemic load or low-glycemic load meals with prescribed energy restriction
      • The AHA-style Step 1 diet (with prescribed energy restriction of 1, 500kcal to 1, 800kcal per day; less than 30% of total calories from fat; less than 10% of total calories from saturated fat).

    • Potential Costs Associated with Application

      Costs of medical nutrition therapy (MNT) sessions vary, however MNT sessions are essential for improved outcomes.

    • Recommendation Narrative

      From AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults (2013)

      Diets for Weight Loss (Dietary Strategies for Weight Loss)
      • 3a. Prescribe a diet to achieve reduced calorie intake for obese or overweight individuals who would benefit from weight loss, as part of a comprehensive lifestyle intervention. Any one of the following methods can be used to reduce food and calorie intake:
        • Prescribe 1, 200kcal to 1, 500kcal per day for women and 1, 500kcal to 1, 800kcal per day for men (kcal levels are usually adjusted for the individual's body weight)
        • Prescribe a 500-kcal-per-day or 750-kcal-per-day energy deficit
        • Prescribe one of the evidence-based diets that restricts certain food types (such as high-carbohydrate foods, low-fiber foods or high-fat foods) in order to create an energy deficit by reduced food intake.
      • NHLBI Grade A (Strong). ACC/AHA Level of Evidence Grade A.

      From the 2010 Dietary Guidelines Advisory Committee (DGAC) Nutrition Evidence Library (NEL) Evidence-Based Systematic Reviews

      • What is the optimal proportion of dietary fat, carbohydrate and protein to lose weight if overweight and obese?
        • There is strong and consistent evidence that when calorie intake is controlled, macronutrient proportion of the diet is not related to losing weight.
      • What is the optimal proportion of dietary fat, carbohydrate and protein to avoid regain in weight-reduced persons?
        • A moderate body of evidence provides no data to suggest that any one macronutrient is more effective than any other for avoiding weight regain in weight-reduced persons.
      • Are low-carbohydrate (less than 45%) hypocaloric diets safe and effective for long-term (more than six months) weight loss or maintenance?
        • A moderate body of evidence demonstrates that diets with less than 45% of calories as carbohydrates are not more successful for long-term weight loss (12 months). There is also some evidence that they may be less safe. In shorter-term studies, low-calorie, high-protein diets may result in greater weight loss, but these differences are not sustained over time.
      • Are high-protein (more than 35%) hypocaloric diets safe and effective for long-term (more than six months) weight loss or maintenance?
        • A moderate amount of evidence demonstrates that intake of dietary patterns with less than 45% calories from carbohydrate or more than 35% calories from protein are not more effective than other diets for weight loss or weight maintenance, are difficult to maintain over the long-term and may be less safe.
      • Is energy density associated with weight loss and weight maintenance in adults (NEL)?
        • Strong and consistent evidence indicates that dietary patterns that are relatively low in energy density improve weight loss and weight maintenance among adults.
      • What is the relationship between glycemic index or glycemic load and body weight?
        • Strong and consistent evidence shows that glycemic index and glycemic load are not associated with body weight and do not lead to greater weight loss or better weight maintenance.

    • Recommendation Strength Rationale

      • The four conclusion statements for Energy Balance and Weight Management, Macronutrient Proportion in support of this recommendation received grades of strong and moderate
      • The conclusion statement for Energy Balance and Weight Management, Energy Density in support of this recommendation received a grade of strong
      • The conclusion statement for Carbohydrates, Glycemic Index/Load in support of this recommendation received a grade of strong
      • ACC/AHA/TOS recommendations either given NHLBI Grade A (strong) or Grade B (moderate), ACC/AHA Level of Evidence Grade A. Recommendation 3a was based on Critical Question Three, which analyzed systematic reviews and meta-analyses (the literature search included those published from January 2000 to October 2011) and added major RCTs published after 2009 with greater than 100 people per treatment arm.

    • Minority Opinions

      Consensus reached.