21 October, 2013
Keep your weight – don't miss breakfast
Here is the perception: skipping breakfast increases hunger throughout the day, making people overeat and seek out snacks to compensate for missing that first – and some would say most important – meal of the day. This belief is based on many studies and was not challenged until recently, when Brown and colleagues published their findings [1].
Basically, what the authors were pointing out was that sometimes science-related beliefs are presumed true even though insufficient evidence exists to support or refute them. They searched various sources of information in regard to the effect of eating breakfast on obesity, and focused on one meta-analysis and three systematic reviews, which included data from 92 relevant articles. They noted that there were only a few relevant randomized controlled trials, which gave a variety of results and were inconsistent in their conclusions.
As for the observational evidence, there was a clear association between breakfast omission and excess weight on the one hand, but this association did not show causation on the other hand. Several methodological flaws were detected in the database as well, such as biased interpretation of one’s own results, improper use of causal language in describing the results, or misleadingly citing others’ results.
To summarize, Brown and colleagues suggested that careful analysis of the data dictates caution, since the belief in the association between eating breakfast and better management of obesity exceeds the strength of scientific evidence.
Comment
People may believe that by omitting breakfast they are reducing their total calorie intake and thereby helping their efforts at weight control. But, in fact, many studies support an opposite view, namely that eating breakfast is important especially as part of weight reduction programs. A typical study that demonstrated the benefits of not missing breakfast examined 52 moderately obese adult women, who were stratified according to their baseline breakfast-eating habits and were randomly assigned to a weight-loss program [2].
The no-breakfast group ate two meals per day and the breakfast group ate three meals per day. The energy contents of the two weight-loss programs were identical. After the 12-week treatment, baseline breakfast eaters lost 8.9 kg in the no-breakfast treatment and 6.2 kg in the breakfast treatment. Baseline breakfast skippers lost 7.7 kg in the breakfast treatment and 6.0 kg in the no-breakfast treatment.
Analyses of behavioral data suggested that eating breakfast helped to reduce dietary fat and minimize impulsive snacking and therefore could be part of a weight-reduction program.
A comprehensive article in the New England Journal of Medicine published earlier this year discussed several obesity-related myths and mis-perceptions, including the issue of eating regular breakfasts [3]. One of the addressed presumptions was that 'Regularly eating (vs. skipping) breakfast is protective against obesity. Skipping breakfast purportedly leads to overeating later in the day'. But, according to the NEJM paper, the true fact is that 'Eating breakfast daily is likely to help only if it is accompanied by an overall reduction in energy intake'.
The take-home message is very clear: in modern times we are exposed to vast quantities of all sorts of information, sometimes leading to creation of 'accepted perceptions'. The above issue is a good example: the importance of having regular breakfasts as part of the strategies to reduce weight has been repeatedly and favorably addressed by the lay-media, scientific, and (USA) government sources. Perhaps this seemingly clear-cut association is not so accurate and deserves further testing.
Amos Pines
Department of Medicine ‘T’, Ichilov Hospital, Tel-Aviv, Israel
References
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 Sep 4. Epub ahead of print
http://www.ncbi.nlm.nih.gov/pubmed/24004890
2. Schlundt DG, Hill JO, Sbrocco T, Pope-Cordle J, Sharp T. The role of breakfast in the treatment of obesity: a randomized clinical trial. Am J Clin Nutr 1992;55:645-51.
http://www.ncbi.nlm.nih.gov/pubmed/1550038
3. Casazza K, Fontaine KR, Astrup A, et al. Myths, presumptions, and facts about obesity. N Engl J Med 2013;368:446-54.
http://www.ncbi.nlm.nih.gov/pubmed/23363498
