Instead of ringing in the new year with my normal binge-fest of Chinese delivery and leftover Christmas cookies, I kicked off 2017 with a three-day fast, followed by two weeks of healthy eating. I wish I could say my swift change in diet was motivated by some holier-than-though resolution to conquer wellness, but that would be a lie. The truth is that a few days after Christmas I got a bad case of food poisoning after eating takeout from the local chicken joint.
I definitely could have done without the salmonella-induced vomiting, stomach cramps and fever, but, on the bright side, I did lose the weight I’d been putting on since adopting a three-servings-per-meal habit around Thanksgiving. Plus, once I was able to get out of bed and return to the working world, I noticed that I felt less “apathetic and bloated” and more “alive and zippy” during the day, and slept much more soundly at night.
I could have started feeling great, day and night, for any number of reasons, but I suspect my (unintentional) crash diet was part of the equation. According to a study published in JAMA last year, calorie resriction is associated with improvements in both overall quality of life and quality and duration of sleep.
The study, first reported on by Time last spring, involved an analysis of a two-year experimental trial called CALERIE 2. For the purpose of assessing how calorie restriction might affect mood, quality of life, sexual function and sleep, the CALERIE 2 researchers randomly sorted 218 healthy adults with BMIs between 22.0 and 28.0 into two groups. One group spent the next two years eating what, and however much, they normally would (which may or may not have involved General Tso's and Snickerdoodles). The other group cut their daily caloric intake by 25 percent.
Weight loss was a clear result for the calorie-cutters — members of the fasting group shed an average of 16.5 pounds, or 10 percent of their body weight, over 24 months. But, the analysis hinted at other possible effects of calorie restriction, particularly in relation to sleep. By the time the one-year mark rolled around, participants in the calorie-restriction group reported increased sleep duration on questionnaires. And at the end of the second year, when they filled out the same questionnaires again, they also reported better overall sleep quality.
More research will need to be done to explain the link between longterm calorie restriction and improved sleep. (Also, it's worth noting that the trial doesn't say anything about the potential sleep benefits of short-term fasting.) For now, the researchers are looking to other studies on weight loss and sleep for answers. For instance, weight loss is thought to mitigate or eliminate sleep apnea — a condition caused by a complete or partial blockage of the airway during sleep. Reduced belly fat has also been linked to better sleep in past studies.
Yet, given that study participants who restricted their calories for two years reported significant improvements in mood, reduced tension, revved-up sex drives and better general health, those willing (and able) to step away from the sugar and fat may be on the right track to having a zippier 2017.