A study suggests eating later in the day can directly impact our biological weight regulation in three key ways: through the number of calories that we burn; our hunger levels; and the way our bodies store fat.
With obesity now affecting hundreds of millions of people worldwide, this is a valuable insight into how the risk of becoming obese could be lowered in a relatively simple way – just by eating our meals a few hours earlier.
Earlier studies had already identified a link between the timing of meals and weight gain, but here the researchers wanted to look at that link more closely, as well as teasing out the biological reasons behind it.
“We wanted to test the mechanisms that may explain why late eating increases obesity risk,” said neuroscientist Frank Scheer, from Brigham and Women’s Hospital in Boston in 2022 when the study was published.
I don’t think we can simply say for certain that a calorie is a calorie no matter when its consumed.
Although evidence is still limited, there are indicators that eating earlier in the day leads to less weightgain.
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My blatantly unscientific quick rationale: if you’re catching your prey late in the day, it was a tough hunt or food might be scarce, better hang on to those calories tightly.
In a slightly more scientific angle, I wonder if it could have to do with changes in digestion processes when sleeping.
I read about this a while ago so my memory is fuzzy on the details; I think the circadian rhythm was a key factor in this.