• Photo for Fat Factors: Sleep, Stress, and the Weight-Gain Connection
    Photo Credit: Nicolas Smith

Fat Factors: Sleep, Stress, and the Weight-Gain Connection

By Beth Sumrell Ehrensberger, MPH, RD

You're eating all the right things and logging sweaty hours at the gym, so what’s with the weight gain? If you’ve put your diet and exercise habits under the microscope, but still aren’t getting results, it may be time to consider how other factors like sleep deprivation and high stress levels may be part of the problem. Learn about these hidden weight-gain factors below, and what you can do to solve them.

Fat Factor: Shirking Shuteye
Everybody’s been there. The mid-afternoon slump hits and you can’t seem to stop fantasizing about those Krispy Kremes in the break room. If you crack under the strain, chances are you lost the battle sometime last night anyway. The combination of sleep deprivation and carbs is a nasty one-two gut punch. One 2004 study examined the sleep habits of men with an average age of 22, and a normal BMI, and found that among those who were sleep deprived (less than four hours of sleep), there was a significant increase in both hunger and appetite. Even worse, the study revealed that the increased appetite was for high carbohydrate, energy dense foods. And the hunger will hit you in the afternoon, when you feel the effects of lack of rest most intensely. That’s why sugary snacks from the vending machine seem irresistible a couple of hours after lunch.

While research on this topic is relatively new, it’s evident that sleep-impacted hormones are actually the culprits behind your expanding behind. Less sleep means a decrease in leptin (the hormone that decreases appetite), and an increase in ghrelin (a hormone that stimulates appetite), spelling unmanageable hunger and out-of-control appetite. Another study by the University of Wisconsin and Stanford University had similar findings: People who get less than 7.7 hours of sleep have a higher BMI than those who get more. Simply stated, when your body hasn’t had enough sleep to recharge, it seeks energy in food. If you want to tighten your belt, you’d better start sawing those logs a little earlier at night.

Fat Factor: Soaring Stress
Maybe you don’t get enough sleep because you’re stressed. But your stress is itself changing your hormones, and not for the better. In fact, the jiggle you feel in your middle might be the result of plain old stress as much as food.

A Yale University study conducted in 2000 found that cortisol, a hormone that is produced in response to stress (either physical or emotional), is responsible for extra inches around your middle. Cortisol is critical to your body’s normal functions since it’s what gives you the burst of energy you need to handle any given stressful situation. This carefully regulated system becomes unbalanced when you’re constantly remaining at a very high stress level—your body can’t burn the cortisol fast enough to keep up with its constant production. The excess cortisol that is released throws hormones like insulin and serotonin out of balance. It also causes a slowdown in metabolism, increases hunger and cravings, and triggers a blood sugar imbalance. Worst of all, excess cortisol cues the body to store fat around your middle.

Abdominal fat doesn’t just add a couple notches to your belt; fat stored around your middle is particularly dangerous, since it raises the risk for cardiovascular disease. In men, a waist measurement of more than 40 inches is considered a cardiovascular red flag. It turns out that the link between cardiovascular disease and stress isn’t only through a tubby waist: Researchers at the Massachusetts-based Lown Cardiovascular Research Foundation recently concluded that people who were able to adequately manage stress are 60 percent less likely to have a heart attack. What’s more, a new 2007 study even indicates a correlation between high abdominal fat during middle age and an increased risk for dementia later in life.

Good old-fashioned exercise is what experts recommend to counter-balance the stress in your life, since it not only helps you to relax, but also burns calories and boosts your metabolism as well. In addition to your cardiovascular workouts, try working in a yoga, Tai Chi, or meditation program to help manage stress.

Fat Factor: Unhealthy Friends
Of course, everybody knows that weight gain isn’t contagious…or is it? A 2007 study published in the New England Journal of Medicine suggests that your friends and even your family can indeed make you fat. If you’re going out with friends for lots of drinks and high calorie appetizers, belong to a family that loves to eat, or live with someone who fills the pantry with chips and chocolate, chances are you will follow suit, too. The study found that the “social norm,” that is, what you perceive to be normal “acceptable” behavior, can be shaped by the everyday habits of the people closest to you. In other words, if you’re surrounded by people who don’t see anything wrong with a little extra cushioning, you probably won’t either—and it’s not likely that you will aspire to do anything to make a change.

Think of it in the inverse: Why do you think running partners exist? Being fit is easier when you have company, and there’s no exception for being overweight, either.

We live in a society brimming with daily stress and impossible demands. While the most health-conscious religiously follow a rigorous fitness regime and carefully consider every bite, other health habits more easily slip through the cracks of a hectic life. But just as too many indulgences can affect your weight, so can your lack of sleep, unmanaged stress, and even the company you keep. Make shuteye a priority and find a way to help manage daily stress. And since accountability is a great motivator, encourage your friends to embrace a healthy diet along with you. By finding a healthy lifestyle balance, you may not only find yourself with a better outlook on life, but in a healthier body, too.