The need for regular meals are a regularly-occurring feature in healthy eating and weight loss advice. I used to believe this myself. But in the last year or two I’ve had to reconsider my thinking on this on this on the basis of my own personal experience as well as people I’ve worked with clinically. Basically, I’ve come to the conclusion that prolonged periods of food avoidance can have benefits for weight loss and health, perhaps through some ability to optimise the functioning of certain hormones including insulin. I was asked earlier this year to write a piece about the concept of ‘intermittent fasting’ for The Times newspaper which you can find here.
One of the more common intermittent fasting strategies is to confine eating to a preset ‘window’ (usually 6-8 hours) during each 24-hour day. I was interested to read of a recent study, albeit in mice, that appears to lend some support for the idea that such a strategy may have benefits for health and weight control [1].
In this study, mice were fed in one of two ways. One group of mice were allowed to eat as much as they liked night and day. Another group, however, had their eating restricted to just 8 hours every 24-hour cycle. The mice ate the same type of diet, and ended up consuming the same amount of calories too. However, the impact on the two groups of mice was different in a number of ways.
For example, those mice with restricted eating ended up weighting significantly less than the other mice. Insulin functioning was improved too (improved insulin sensitivity is generally taken as a good thing and something that would help reduce the risk of weight gain and chronic diseases including type 2 diabetes over time). Functioning of the hormone leptin was improved too, which is important as this hormone is known to help speed the metabolism (and may suppress appetite too).
The mice that were restricted in their feeding has lower levels of inflammation. This is perhaps important because inflammation is believed to impair the functioning of both insulin and leptin. These mice enjoyed relative protection from liver damage too.
Mice are not men, so we cannot assume that the findings of this study apply directly to human beings. However, I do think this sort of research serves to remind us that it’s not just what we eat, but when we eat it, that might have some influence on weight and wellbeing. And even though the research is conducted in animals, it provides at least some support for the idea that contracting the window during which we eat each day might bring us benefits.
References:
1. Hatori M, et al. Time-Restricted Feeding without Reducing Caloric Intake Prevents Metabolic Diseases in Mice Fed a High-Fat Diet. Cell Metabolism 17 May 2012