Journal Title (Medline/Pubmed accepted abbreviation): J Int Soc Sports Nutr
doi (if applicable):10.1186/1550-2783-8-4
Article type:Position statement
Summary of article:
This article is a position statement from the International Society of Sports Nutrition on meal frequency. Given the near epidemic status of obesity in the United States, much attention has focused on eating patterns and the effects they can have on adiposity and health factors. Research evaluating meal frequency has been encouraged, as some evidence suggests that “nibblers/grazers” (individuals who eat smaller, more frequent meals) may be at a metabolic advantage over “gorgers” (individuals who eat fewer, larger meals). The majority of studies have been focused on obese subjects, with little attention paid to the effects of meal frequency on the physically active. The authors sought to review research findings in which meal frequency was an independent variable in any markers of body composition, health markers, thermic food effect, energy expenditure, nitrogen retention, and satiety. Further, the authors sought to interpret the available literature for athletic populations.
Animal models and human studies were reviewed. Results on body fat loss, specifically, were conveniently presented in tabular form and were grouped into either studies that support the effectiveness of increased meal frequency on weight loss/fat loss, or studies that refuted such effectiveness. More studies refuted the effectiveness of increased meal frequency than supported it. Several studies demonstrated improvements in blood lipoproteins, markers of glucose kinetics, and glucose metabolism with smaller, more frequent meals. Studies did not support an improvement in overall metabolic rate with smaller meals; however, increased fatty acid oxidation and decreased carbohydrate oxidation were reported. A separate variable appears to be protein intake, and the current literature as well as future studies should be reviewed in that context. Finally, subjects who ate smaller, more frequent meals consistently reported greater feelings of satiety.
The position statement is composed of 5 main points:
- Increasing meal frequency does not improve body composition for sedentary subjects.
- Increasing meal frequency during hypocaloric periods for athletic individuals may preserve lean muscle mass as long as protein intake is sufficient.
- Increased meal frequency appears to favorably affect blood markers of health, in particular low-density lipoprotein, cholesterol, and insulin.
- Increased meal frequency does not appear to improve thermogenesis, energy expenditure, or resting metabolic rate.
- Increased meal frequency appears to suppress feelings of hunger and improve appetite control.
Interpretation of findings/Key practice applications:
It is difficult to definitively determine whether there is a relationship between meal frequency and body composition due to confounding variables such as exercise, under-reporting (which is common in both obese and non-obese populations), and smoking status. Overall, the evidence does not support a role for increased meal frequency alone in decreasing weight or improving body composition. This is somewhat surprising given the colloquial understanding of the “benefits” of increased meal frequency. However, additional effects of increased meal frequency may still have an indirect role in aiding subjects in weight loss. Improvements in lipoproteins and glucose metabolism have significant effects on overall health, and improved glucose metabolism may discourage binge eating. In addition, subjects who ate meals more frequently reported higher levels of satiety and thus may eat less overall. These factors will undeniably affect body weight composition and weight loss. Indeed, the authors suggest that the potential to decrease feelings of hunger is, in and of itself, a possible justification to promote smaller, more frequent meals. A limitation of this publication is the lack of a definition for “adequate intake of protein.”