"Anytime you’re stressed, you probably go for food," Dr. Seltzer says. (Have we met?!) That’s because cortisol, the stress hormone, stokes your appetite for sugary, fatty foods. No wonder it’s associated with higher body weight, according to a 2007 Obesity study that quantified chronic stress exposure by looking at cortisol concentrations in more than 2,000 adults’ hair.
"Crash diets (dramatically cutting down how much you eat) might help you to lose a few pounds at first, but they’re hard to sustain and won’t help you keep the weight off. It might seem like a quick and easy option, but eating too few calories can actually do more harm than good. If your calorie intake dips too low, your body could go into starvation mode. This will slow down your metabolism, making it harder for your body to lose weight. Make sensible, healthy changes to your lifestyle that you can stick to and avoid the fad diets."
For even more impressive effects on body composition: aim for exercise forms which elicit a positive hormonal response. This means lifting really heavy things (strength training), or interval training. Such exercise increases levels of the sex hormone testosterone (primarily in men) as well as growth hormone. Not only do greater levels of these hormones increase your muscle mass, but they also decrease your visceral fat (belly fat) in the long term.
"When we’re lacking in sleep, our body’s hormones get thrown off balance which can impact our hunger levels the next day. We all have two hormones that affect our appetite: ghrelin and leptin. When we don’t get enough sleep, our ghrelin levels (the hormone that makes us feel hungry) rise, and our leptin levels (the hormone that makes us feel full) drop. This means that when we’re awake, we tend to eat more but feel less satisfied. Try going to bed a little earlier than usual to avoid this imbalance and remember to remove any distractions that might prevent you from nodding off."