Since history, dinner has been entrenched in our minds as the main meal of the day.
There are many reasons why. Psychologically, we find it very comforting to look forward to a big meal after a long and tiring day of work or study. Dinner is a social thing too. For families, it’s a time when everyone is at home and finally together. Our friends are also more likely to be free during dinner time and so out to dinner we go.
For many of us, our typical dietary pattern for the day might look like this. A small amount of breakfast followed by a moderate amount of lunch and then boom! a big dinner that we actually feel quite full from. Of course this will vary across individuals due to our lifestyle but on average, it is likely that.
But what if this way of eating, i.e. eating more towards the end of the day, is actually detrimental for our desire to lose weight?
Losing Weight with a Big Breakfast
A study assigned two groups of overweight and obese women the same number of calories for the day. However, the calories were distributed differently amongst the groups. One group ate 50% of their calories for breakfast, 30% for lunch and 20% for dinner. The second group ate the opposite proportions: 20%, 30% and 50% for breakfast, lunch and dinner respectively.
The results are really cool. The group that ate the majority of their calories in the morning lost more weight compared to the other group. It was a substantial amount of weight too. The morning group lost around 9kg while the evening group lost 4kg… that’s more than double in difference!
Many other studies have also shown similar findings. Simply eating a main meal at lunch showed favourable weight loss results compared to eating a main meal at dinnertime.
However, losing weight is not the only benefit of this eating pattern. Researchers have also documented improvements in waist circumference, insulin resistance, cravings and satiety.
Our Internal Clock
All of these results are tied together by our circadian rhythm. Colloquially referred to as our ‘internal clock’, it plays an important role in regulating our metabolism and behaviour including food consumption.
Our circadian rhythm is based off the earth’s light and darkness, i.e. day and night. It’s a routine system that doesn’t like to be disrupted. But when it is for whatever reason (such as eating late or eating more than we used to), our metabolism is also disrupted. Unfortunately, evidence has shown that this can lead to weight gain and obesity.
Become An Early Bird
So to take full advantage of our circadian rhythm, we should be eating most of our calories earlier in the day. And for those of us who don’t count calories, we can think of it as eating breakfast or lunch as our main meal followed by a smaller meal at dinner.
Of course this is just one aspect of weight management. What we eat at breakfast, lunch and dinner matters very much too.
But certainly, I know I’ll be using this as one of my reasons to brunch more!
- Jakubowicz D, Barnea M, Wainstein J, Froy O. High caloric intake at breakfast vs. dinner differentially influences weight loss of overweight and obese women. Obesity (Silver Spring). 2013;21(12):2504‐2512. https://pubmed.ncbi.nlm.nih.gov/23512957/
- Lombardo M, Bellia A, Padua E, et al. Morning meal more efficient for fat loss in a 3-month lifestyle intervention. J Am Coll Nutr. 2014;33(3):198‐205. https://pubmed.ncbi.nlm.nih.gov/24809437/
- Madjd A, Taylor MA, Delavari A, Malekzadeh R, Macdonald IA, Farshchi HR. Beneficial effect of high energy intake at lunch rather than dinner on weight loss in healthy obese women in a weight-loss program: a randomized clinical trial. Am J Clin Nutr. 2016;104(4):982‐989. https://pubmed.ncbi.nlm.nih.gov/27581472/
- Raynor HA, Li F, Cardoso C. Daily pattern of energy distribution and weight loss. Physiol Behav. 2018;192:167‐172. https://pubmed.ncbi.nlm.nih.gov/29471076/?from_term=Daily+pattern+of+energy+distribution+and+weight+loss&from_pos=1
- Rouhani MH, Surkan PJ, Azadbakht L. The effect of preload/meal energy density on energy intake in a subsequent meal: A systematic review and meta-analysis. Eat Behav. 2017;26:6‐15. https://pubmed.ncbi.nlm.nih.gov/28131006/