10 Science-Backed Ways to Help Prevent Obesity

There's no shortage of strategies and tips out there to help you lose weight. But what if you want to avoid putting on weight in the first place?

Forty-two percent of U.S. adults today are affected by obesity, which is defined as having a body mass index (BMI) of 30 or more, according to data from the Centers for Disease Control and Prevention (CDC). That percentage has gone up since 2000 — and it's predicted to increase even more, per a December 2019 analysis from the ‌New England Journal of Medicine‌ (NEJM).

The factors behind our growing obesity rates are complex, to say the least. But there are plenty of proven ways to keep your weight in check. Here's what you can do — starting right now — to reduce your risk for obesity.

It's no secret that having too much body fat can be bad for your health. But when you consider the laundry list of conditions for which obesity increases your risk, the importance of being at a healthy weight really hits home. According to the CDC, people with obesity are more likely to experience:

• High blood pressure
• High cholesterol
• Heart disease
• Type 2 diabetes
• Osteoarthritis
• Sleep apnea
• Many types of cancer
• Lower quality of life
• Mental illness
• Body pains and decreased functioning
• Higher risk of death overall

You'll greatly improve your health by losing weight, of course. But you're better off avoiding gaining too much weight in the first place. Once you are living with obesity, it becomes harder to get back to a healthy weight, per a September 2015 study in the ‌American Journal of Public Health‌.

"If you're seriously overweight, your body naturally seeks a larger number of calories in order to maintain that weight. And that larger amount of food is what your brain says you need, so you eat more. It's really a vicious circle," explains Scott A. Cunneen, MD, director of metabolic and bariatric surgery at Cedars-Sinai Medical Center in Los Angeles, and author of ‌Weighty Issues: Getting the Skinny on Weight-Loss Surgery‌.

That's not to say it's impossible to get to a healthier size — far from it. While you can always work to lose weight, "health professionals are realizing that prevention is better than cure when it comes to managing your weight," says weight-management expert Naveen Gupta, MD.

If prevention is the best medicine for obesity, what exactly should you be doing to keep your weight in check? Science shows it all comes down to forming healthy lifestyle habits and sticking with them.

There's a genetic component to obesity, and you may be more prone to gaining weight easily if your family members have obesity, per the CDC. But genes aren't everything — environmental changes are also a key factor, Dr. Gupta says. You can always take measures to keep your weight in a healthy place.

Here are 10 evidence-based steps to help prevent weight gain.

If you keep just one thing in mind about weight gain, it should be this: When you eat more calories than your body needs for energy, the extra gets stored as fat.

"Portion control is one of the most important things for maintaining your weight," says Keri Gans, RDN, CDN, author of ‌The Small Change Diet‌.

That's true even for healthy foods. Whether it's pepperoni pizza or brown rice with tofu and veggies, eating more than you need will ultimately cause your weight to go up. Paying attention to how you feel as you're eating and stopping when you're satisfied is one way to avoid taking in too much food, per the CDC.

Also: Get familiar with what recommended portion sizes actually look like. Very often, they're smaller than you think.

Another strategy is to fill more of your plate with fruits and vegetables so you get what feels like a generous portion for fewer calories. "Instead of a huge bowl of pasta, for instance, cut the portion of pasta in half and add lots of veggies to bulk up the dish," Gans says.

Simply eating a fiber-rich diet — around 30 grams per day — may be enough to help you manage your weight, per February 2015 research in the ‌Annals of Internal Medicine‌.

"High-fiber foods take longer to digest and may help to stabilize blood sugars, resulting in increased satiety levels," Gans explains. And the more satisfied you feel after eating, the less likely you'll be to scrounge for a snack later on.

Whole grains, beans and even nuts and seeds can all be good sources of fiber. But when it comes to weight, fiber-rich produce like berries, apples, pears and non-starchy vegetables are an especially weight-friendly choice, per analysis published in September 2015 in ‌PLOS Medicine‌. Not only do they serve up plenty of roughage, they're also very low in calories.

The more junky snacks you eat, the more likely you are to have obesity, per an October 2016 study published in the ‌American Clinical Journal of Nutrition‌.

Not only are things like cookies, crackers, chips and baked goods high in empty calories, but the fact that they're low in fiber and high in refined carbs means they'll spike your blood sugar and leave you hungry again shortly after eating, per Harvard Health Publishing.

That's not to say you can never have a brownie or a cupcake again. But it's worth learning to enjoy them in a healthier way.

"Instead of removing chocolate from your diet altogether, try having one square right after a meal, which can potentially stop a craving before it gets out of control," Gans says.

Drinking a single sweetened beverage like soda, juice or sweetened tea each day could result in a weight gain of up to five pounds in a year, according to the Harvard T.H. Chan School of Public Health. That's because sweetened drinks are high in sugary calories but don't actually fill you up — so you don't compensate for those calories by eating less.

Soda is "a well-known enemy of weight-control success," Dr. Cunneen says.

And while diet soda is calorie-free, it may not be a better choice when it comes to managing your weight, according to March 2015 findings published in the ‌Journal of the American Geriatrics Society‌.

"The artificial sweeteners found in diet soda may trick the body into reacting as if it were real sugar, so that the inclination is generated to eat other sugar-laden food," Dr. Cunneen explains.

The more TV and screen time you log each day, the more likely you are to be overweight. Sitting in front of a screen prompts your body to store fat instead of burning it for energy, Dr. Gupta explains. It might make you more likely to eat more snacks, too.

Simply cutting back on screen use has been shown to help people lower their BMIs, per a December 2009 study in the ‌Archives of Internal Medicine‌.

There's a good chance that doing so will encourage you to naturally move more: Without the TV on, you might find yourself going for a walk or finally clearing out that closet. And the more you move, the more fat your body will burn, Dr. Gupta says.

Speaking of curbing screen time, it's worth finding ways to incorporate more activity into your day overall. Aim to get at least 150 minutes of moderate exercise per week, which breaks down to around 30 minutes per day, per the CDC.

But that's really just a bare minimum. "Studies indicate that activity needs to increase to one hour a day to lose any significant weight," Dr. Cunneen says. "The more you move, the better you'll do," he says.

That's not to say you need to log hours and hours at the gym every day. Take up a hobby that you love that gets your heart pumping — like hiking, playing tennis or riding your bike. And think about ways to incorporate more movement into everyday activities, like walking to do errands instead of driving or meeting a friend for a stroll instead of grabbing lunch together.

Restaurants tend to add more fat, salt and sugar to their food and offer much bigger portions than you'd serve yourself at home, resulting in higher-calorie meals.

"Cooking at home gives you more control over the amount of food you're served," Gans says. In fact, those who eat home-cooked meals five times a week or more are 28 percent less likely to be overweight compared to those who eat at home less than three times a week, according to August 2017 research in the ‌International Journal of Behavioral Nutrition and Physical Activity‌.

No need to avoid dining out altogether. But it's worth saving restaurant meals for special occasions and adopting strategies to help you avoid overeating.

"Get into the habit of ordering a side of vegetables with your meal, then eating only half your entrée and taking the other half home," Gans suggests.

You might not realize it, but your mood can have a major influence on what — and how much — you eat.

"When we're stressed we're more likely to grab something on the go with no regard to how healthy it is," Dr. Gupta says. "We're also more likely to overeat or overindulge." Over time, that can add up to excess pounds.

Taking steps to manage your stress can help. Adults with obesity who participated in an eight-week stress management plan including things like deep breathing and guided imagery lost significantly more weight compared to those who didn't, per a December 2018 study in the ‌Journal of Molecular Biochemistry‌. Plus, they also experienced less depression and anxiety.

Mapping out every item on your menu every single day is unrealistic. But making food choices on the fly ups the chances that you'll opt for something quick or convenient (hello, takeout!), which might not always be the best option for your weight.

"The more you're prepared, the less likely you are to make unhealthy choices," Gans says.

Before going shopping for the week, try outlining your breakfasts, lunches, dinners and snacks and making a grocery list based on what you need to make complete meals. "For example, don't just buy a piece of chicken. Also buy the veggie you'd have it with and a carbohydrate like a sweet potato," Gans says.

Keeping your pantry and freezer stocked with wholesome staples can give you easy, healthy options for those times when you haven't had a chance to plan. For instance, you can make a quick dinner with a box of whole-wheat pasta, a can of chickpeas and a bag of frozen veggies in about the same amount of time it would take for a pizza delivery order to arrive.

If you're not logging the recommended seven to nine hours of shut-eye per night, start.

"A healthy sleep pattern is essential in maintaining a healthier weight and overall good health," Dr. Cunneen says. On the flip side, adults who regularly snooze for less than seven hours a night have higher body mass indexes and are more likely to develop obesity, per an October 2018 review in ‌BMJ Open Sport and Exercise Medicine‌.

"When you sleep less and spend more hours awake, the hunger hormone ghrelin increases and the satiety hormone leptin decreases," Dr. Cunneen explains. That means it takes more food to make you satisfied. And chances are you won't be munching on salad to fill your belly.

When you're sleep deprived, you're more likely to gravitate toward comforting high-carb, high-calorie fare like cookies or mac and cheese, according to the Mayo Clinic.