New research shed light on several important areas when it comes to understanding weight and metabolism. We picked three of our favorite studies from 2016 to share. The first study looks at the link between late night eating and weight gain, and the second examines why maintaining your ideal weight gets easier once you make it past year one.
Weight, circadian rhythm and late night eating
Did you know when you eat– not just what you eat - can have a surprisingly big impact on your metabolism? This has to do with the link between our eating behaviors and circadian rhythm. It’s been observed that eating late at night – a time when, according to our natural body’s clock, you should be sleeping – can cause us to eat more and gain weight.
A team of researchers in Japan wanted to get to the bottom of why this happens. They took two groups of mice and fed them both a high-fat, high-sugar diet. One group of mice was fed this rich food during their regular sleeping time; the other group was fed during normal waking hours.
This is what they found: The mice that were fed when they would normally be sleeping voluntarily ate about 10% more, and weighed about 10% more than their counterparts.
This is a significant difference just because of feeding time. The likely reason for this was revealed in the blood work. It appears that the feeding regimen that mimicked late night eating impacted the activity of appetite regulating genes: It turned-up the genes that stimulate appetite, while turning down the ones that suppress appetite.
Additionally, levels of leptin, the hormone that tells the brain when we’ve consumed enough calories, were significantly higher in the mice that were eating during sleeping hours. This suggests leptin resistance is occurring, meaning the brain isn’t getting the message to stop eating.
This research suggests that similar physiological effects could be seen in humans who eat when they would typically be asleep. Bottom line, if you want to avoid gaining weight and wreaking havoc on your metabolism, it’s probably best not to mess with your circadian rhythm. Eat during active waking hours, and save late night hours for sleep.
You can check out the full study here.
Keeping the weight off – it gets easier after one year
Anyone who has ever dieted has probably experienced this: The body “fights” weights loss in a number of ways. Energy expenditure tends to slow down, and hormones associated with appetite and motivation often shift in ways that make you feel less satisfied by the food you’re eating.
The big question is: Will the body ever “accept” this new lighter body weight, from a physiological standpoint, so that keeping weight off becomes less of a struggle?
In this study, twenty healthy obese participants achieved a weight loss of 13% body mass through an 8-week calorie-restricted diet, and they kept the weight off for one year.
The researchers measured their hormone levels - specifically those associated with appetite – in response to eating a 600-calorie meal. The test was performed at three different points: before weight loss, immediately after weight loss, and after one year of weight maintenance.
What they found was that immediately after losing weight, certain hormones were suggestive of what we might call a “famine” state. For example, ghrelin – a hormone associated with increased hunger – had risen significantly.
However, after one year of weight loss maintenance, most hormone levels returned to how they were before weight loss. This finding suggests that these appetite-modulating hormones can actually adjust to a new body weight in a way that makes it easier to maintain.
This is incredibly encouraging news for those of us who are trying to lose weight and more importantly keep the weight off for years to come. It may become easier for you to maintain weight loss – so long as you are able to stick with it for at least a year.
Wait, now high protein during weight loss isn’t good?
Lastly, high protein intake is good for dieting, right? Well, a recent study cast doubt in the health effects of protein while on a weight loss diet, so we brought in an expert to discuss the implications of this study. Listen to the podcast here.
Ginny Robards is a researcher with an avid interest in personal health and digital therapeutics. She's driven to help people get a better return on their efforts to be healthy. When she's not writing about health science, she relaxes by reading about nutrition, bugs, strength training, and genetics.
To learn more, and to read the full-length article, please visit the Dan’s Plan blog.
Main Photo Credit: Africa Studio/shutterstock.com; Second Photo Credit: kizer13/shutterstock.com; Third Photo Credit: sacura/shutterstock.com; Fourth Photo Credit: Liliya Kandrashevich/shutterstock.com