In late 2013, the health halo surrounding breakfast was dented by an article published in The American Journal of Clinical Nutrition questioning the scientific evidence supporting recommendations to consume breakfast to achieve and maintain a healthy body weight.1 The authors argued that the overwhelming majority of the evidence was based on observational studies identifying associations between breakfast and body weight. Very few randomized controlled trials (RCTs) specifically evaluating theeffects of daily breakfast consumption compared to no breakfast, on body weight outcomes, were available, and those that had been published did not strongly support a benefit of breakfast. Since then, several RCTs evaluating breakfast consumption have been published, better defining the impact of regular breakfast meals on energy balance, with unexpected and intriguing results.
Researchers at the University of Alabama-Birmingham recently published results from a 16-week weight loss trial in 309 overweight and obese adults (aged 20-65 y) randomly assigned to receive instructions to either consume breakfast or skip breakfast. 2 Compliance within each group was high, with more than 90% of participants following their instructions. There were no differences between groups for weight loss, suggesting that a general recommendation to eat breakfast is not influential in promoting weight loss in those trying to lose weight. It is important to note that breakfast type was not controlled in this study, an important consideration in light of prior evidence showing greater satiety with higher protein breakfasts.3
While the weight loss results may seem perplexing given the evidence linking breakfast consumption to lower body mass indices, results from another RCT in the same journal suggest that breakfast may impart a benefit on a different aspect of energy balance. Researchers from the University of Bath and Queen’s Medical Centre in the United Kingdom compared the effects of a prescribed breakfast meal (≥700 kcal before 11:00 am) to extended fasting (0 kcal until noon) on energy expenditure (via accelerometer) and energy intake (via food diaries) in lean adults over 6 weeks.4 Results were interesting, in that the breakfast eaters were more physically active, burning approximately 400 more kcal a day in activity (mostly light-intensity activity). Energy intake was also increased in the breakfast eaters, with no differences between groups for changes in body weight. The authors suggest that the availability of glucose in the morning provides the fuel necessary to facilitate physical activity. Whether this same outcome will be seen in overweight or obese adults remains to be determined.
At the very least, the topic of breakfast is getting a lot more interesting!
1) Brown AW, Bohan Brown MM, Allison DB. Belief beyond the evidence: using the proposed effect of breakfast on obesity to show 2 practices that distort scientific evidence. Am J Clin Nutr. 2013;98:1298-308.
2) Dhurandhar EJ, Dawson J, Alcorn A, Larsen LH, Thomas EA, Cardel M, Bourland AC, Astrup A, St-Onge MP, Hill JO, Apovian CM, Shikany JM, Allison DB. The effectiveness of breakfast recommendations on weight loss: a randomized controlled trial. Am J Clin Nutr. 2014 Jun 4. [Epub ahead of print]
3) Westerterp-Plantenga MS, Lemmens SG, Westerterp KR. Dietary protein – its role in satiety, energetics, weight loss and health. Br J Nutr. 2012;108 Suppl 2:S105-12.
4) Betts JA, Richardson JD, Chowdhury EA, Holman GD, Tsintzas K, Thompson D. The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults. Am J Clin Nutr. 2014 Jun 4. [Epub ahead of print]