Some of the most popular advice on food in recent years have focused on the idea that right time of meals can make a big difference in the amount of weight you lose.
For a long time, it was said that, in order to lose weight, it would be better to eat a large meal at the beginning of the day and reduce the portion of later meals.
The logic behind this theory is understandable, especially considering that almost all body cells follow the same 24-hour cycle as we do. You circadian clocks are found throughout the body and regulate the daily rhythms of most of our biological functionsincluding the metabolism.
Because of these metabolic rhythms, scientists have proposed that the way we process meals varies at different times of the day. This field of research is called “chrononutrition” and has great potential to help improve people’s health.
Two studies from 2013 indicated that consuming more calories earlier in the day and fewer calories at night helps people lose weight. But a major new study finds that while the relative size of servings of Breakfast and dinner influence the appetite reported by the participants, it has no effect on metabolism and weight loss.
To investigate the link between breakfast and dinner portion sizes and your effect on hungera team of researchers from the Universities of Aberdeen and Surrey in United Kingdomperformed a controlled study in healthy people, but overweight🇧🇷 The participants were given two diets, each lasting four weeks: a big breakfast and a small dinner and a small breakfast and a big dinner. Lunches were kept the same.
We provided all meals so we knew exactly how many calories study participants were consuming. We measured participants’ metabolisms and monitored how many calories they burned.
All study participants experienced both dietary conditions, so that the effect of meal patterns could be compared in the same people.
Our prediction was that the big breakfast and small dinner would increase calorie burn and weight loss. But the results of the experiment found no difference in body weight, or any biological measure of energy use, between the two meal patterns.
Measures of energy expenditure included basic metabolic rate (how many calories your body consumes at rest), physical activity, and use of a chemical form of water that allows measurement of total daily energy expenditure.
There were also no differences in daily levels of glucose, insulin or blood lipids🇧🇷 This is important because changes in these factors in the blood are associated with metabolic health.
Our conclusions are consistent with studies of short-term mealtimes (one to six days) in which participants live in a laboratory breathing chamber (a small, airtight room equipped with basic comforts) for the duration of the experiment.
Taken together, the research indicates that the way our bodies process calories in the morning and evening does not, comparatively, influence weight loss in the way reported in other studies.
In our study, the only difference was a change in feelings of hunger and related factors, such as how much food participants wanted to eat, as reported by themselves.
Throughout the day, the pattern of eating large breakfasts and small dinners caused participants to report being less hungry throughout the day. This effect can be useful for people looking to lose weight, as it can help them control their hunger better and eat less.
As with all research, our study faced some limitations. We only studied participants for four weeks, for each meal pattern.
Previous research has shown greater differences in the effects of earlier and later energy intake after four weeks. But the fact that neither calories eaten nor calories burned changed over the four weeks demonstrates that body loss probably would not have changed had the study been longer.
Study participants were allowed to choose the exact time of each meal. But even so, the time difference in each meal pattern was minimal.
Chrononutrition remains a fascinating area of research, and there is growing evidence that meal timing can play an important role in improving the health of many people. But our latest research indicates that the time of day you eat your biggest meal isn’t as important to weight loss as previously thought.
* Jonathan Johnston is Professor of Chronobiology and Integrative Physiology at the University of Surrey, UK.
Alex Johnstone is Professor of Nutrition at the Rowett Institute at the University of Aberdeen, UK.
Peter Morgan is a professor at the University of Aberdeen, UK.
This article was originally published on the academic news site The Conversation and republished under a Creative Commons license. read on here the original English version.
The Portuguese version was published on here.