Where does it come from?
It has long been thought that by consuming frequent smaller meals, metabolic rate is increased, resulting in a greater energy deficit when compared to eating infrequent larger meals; all other things being equal (calories, protein etc).
The theory may have stemmed from some early observational studies showing that people with a lower Body Mass Index (BMI) tend to eat smaller, more frequent meals.
There is some research to suggest higher meal frequency may have some impact on muscle mass, which could have spread to cover fat loss and optimal body composition through “memetic mutation” common in the health and fitness industry . Whatever the case, the assumed link between higher meal frequency and increased fat loss is now a highly praised pillar of many fat loss diets.
Is it true?
Whilst some research has shown frequent, smaller meals to increase metabolic rate, other studies show an inverse effect, with higher meal frequency thought to reduce satiety and increase overall calorie intake . However, it is important to note that these observational studies don’t tell us much either way.
Of far more significance is the weight of evidence from controlled studies, suggesting that meal frequency has no effect on fat loss when subjects are consuming a hypocaloric diet (diet with an energy deficit) .
Fear that fasting can reduce metabolic rate has also been put to bed. Research on alternate-day fasting showed an increase in metabolic rate following 36 hours of fasting . This isn’t to mention the other possible benefits of fasting, including improved insulin resistance and cardiovascular health markers [5, 6].
How often should you eat?
If you find that eating frequent smaller meals enables you to better adhere to a hypocaloric diet then keep doing it. However it will not provide any added benefit as compared to eating the same quantity of food in larger, less frequent meals.
In other words, meal frequency has no significant impact on fat loss, so focus on daily protein, fat and carbohydrate goals, not nutrient timing.
- Munsters, M.J. and W.H. Saris, Effects of meal frequency on metabolic profiles and substrate partitioning in lean healthy males. PLoS One, 2012. 7(6): p. e38632.
- Howarth, N.C., et al., Eating patterns and dietary composition in relation to BMI in younger and older adults. Int J Obes (Lond), 2007. 31(4): p. 675-84.
- Bellisle, F., R. McDevitt, and A.M. Prentice, Meal frequency and energy balance. Br J Nutr, 1997. 77 Suppl 1: p. S57-70.
- Heilbronn, L.K., et al., Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism. Am J Clin Nutr, 2005. 81(1): p. 69-73.
- Beigy, M., et al., Alternate-day fasting diet improves fructose-induced insulin resistance in mice. J Anim Physiol Anim Nutr (Berl), 2013. 97(6): p. 1125-31.
- Bhutani, S., et al., Improvements in coronary heart disease risk indicators by alternate-day fasting involve adipose tissue modulations. Obesity (Silver Spring), 2010. 18(11): p. 2152-9.