It’s March, which means we’re two months into our New Year’s resolutions! If you decided to adopt intermittent fasting (IF) this year, you may want to fill up on these facts.
Intermittent fasting, the voluntary abstinence from food and non-water beverages for determined timeframes, is a popular weight loss approach for young adults. Like oil and water, support for IF has been divided, with some pro-IF arguments including:
Our ancestors’ diets (scarcity in the hunter-gatherer days primed humans to function on inconsistent caloric intake)
The obesity epidemic (which occurred after the recommendation to consume three meals a day plus snacks)
Improved cognitive function (in animal studies).
A recent studied published in Obesity evaluated the effects of IF with or without calorie restriction (CR) in obese women over 8 weeks. The result: IF promoted weight loss when combined with CR (versus IF, CR or no dietary change), which is no surprise since this sounds like a recipe for weight loss.
But interestingly, this group showed decreased markers for heart disease (e.g. total- and low-density lipoprotein cholesterol, non-esterified fatty acids) relative to IF or CR alone. Even more interestingly, IF without CR transiently increased diabetes risk markers and did not improve metabolic parameters compared to other groups.
Before you decide to cut out your daily meals, be advised this study was short-term and cannot be generalized to other populations. In fact, much of the evidence for IF comes from underpowered studies over short periods, often in persons with pre-existing conditions like obesity or diabetes. So be sure to take IF with a grain of salt… but only on fed days.