With all the dieting advice around, the question is, should I eat breakfast or fast? Some people who do intermittent fasting eat for 10 hours and fast for 14 hours. On this diet plan you are finishing your dinner at 7PM, skip breakfast and have a brunch at 11 AM the following morning followed by dinner in the evening. This stabilizes diabetes, helps you to lose a bit of weight and prevents cardiovascular disease to a certain extent. But not everybody likes to skip breakfast.
An Israeli study about breakfast and dinner sizes
There is a 2013 Israeli study that investigated how the size of breakfast and dinner influences weight loss and triglyceride levels in the blood. Both diets that were examined had 1400 calories per day and they went on for 12 weeks. Both groups had a lunch consisting of 500 calories. The big breakfast group consumed 700 calories for breakfast and had a small dinner with only 200 calories. The other group, called the big dinner group, ate a small breakfast with 200 calories and a dinner with 700 calories.
Results of the big breakfast group versus the big dinner group
After 12 weeks the big breakfast group had lost 2 ½ times more weight than the big dinner group (8.7 pounds for the big breakfast group; 3.6 pounds for the big dinner group). But this was not all. The big breakfast group also lost 4 inches more in their waist and had a 33% drop in their triglyceride levels compared to the big dinner group. The big dinner group had a 14.6% increase in triglycerides. The fasting insulin level was lower as well in the big breakfast group. There were other markers that indicated that the big breakfast group had a lower risk for type 2 diabetes and cardiovascular disease. It appeared to the researchers that the big breakfast group was metabolically in sync with the circadian hormone rhythm and they felt that this accounts for the metabolic differences of these two groups as the overall calorie count per day was the same.
Should I eat breakfast or fast? Calorie-burning larger in the morning
A smaller study looked at the number of calories burnt during the day. They came to the conclusion that in when the body is sync with the circadian rhythm it burns 2 ½ more calories in the morning than in the rest of the day. This likely is the reason why in the above study (big breakfast group versus the big dinner group) there was 2 ½ times more weight loss in the big breakfast group. When a person fasts, the advantage of the higher calorie-burning is lost in the morning. As explained above, some people who do intermittent fasting eat for 10 hours and fast for 14 hours. On this diet plan you are finishing your dinner at 7PM, skip breakfast and have a brunch at 11 AM the following morning. But from a circadian and caloric point of view this does not make sense. I have always enjoyed a big breakfast and a smaller dinner with a salad. But I am also doing a monthly fasting mimicking diet (FMD).
Conclusion
The question is not new: should I eat breakfast or fast? We finally have the studies that clearly tell us the answer. Our metabolism is most active in the morning due to the circadian rhythm. We burn 2 ½ times more calories than in the evening. If you fast and have no breakfast, you are missing the opportunity and you may gain weight with the food you eat for the rest of the day. However, a study showed that if you eat a large breakfast (700 calories) and a small dinner (200 calories) you will lose the pounds and melt the inches. The reason is that you are in sync with the circadian rhythm and your metabolism. But it is not only about weight loss.
A big breakfast helps you lose weight
The study showed that a big breakfast lowers your triglycerides and your fasting insulin level. There was a lower risk of the big breakfast group to develop type 2 diabetes and cardiovascular disease. By eating right, we can prevent premature heart attacks and strokes. Eat your breakfast and have smaller meals for the rest of the day!