By Yasmine S. Ali, MD, MSCI 

 Medically reviewed by Jonathan Purtell, RDN

Preventing obesity involves making healthy lifestyle choices every day. To prevent obesity, you need to stay active, follow a healthy diet, and get adequate sleep. Obesity prevention also involves saying no to certain preferences, like soft drinks, or driving short distances when you could walk instead.

Obesity is generally defined as a chronic disease characterized by excessive body fat. More than 42% of adults and 19% of children and adolescents in the U.S. have obesity, and those numbers are rising.1

National Institute of Diabetes and Digestive and Kidney Diseases. Overweight and obesity statistics.

 Obesity is often caused by a combination of risk factors, including genetics, poor diet, sedentary behaviors, medical conditions, and lack of access to healthy foods.

While obesity prevention should start in childhood, it is never too late to start making healthier choices. This article discusses how to prevent obesity starting in childhood and later in life. It includes diet, exercise, and lifestyle strategies, along with how these strategies can reduce your obesity risk.

Daniel Llao Calvet / Getty Images

Preventing Obesity in Childhood

Obesity often begins in childhood. Research shows that if a person has obesity at age five, they are more likely to have obesity as an adult. Conversely, if a child does not have obesity at age 5, their lifetime risk of obesity is significantly lower.2

Obesity results from a combination of genetic, environmental, and lifestyle factors. Although families cannot change their genes, they can model healthy lifestyle patterns for children to start preventing obesity from a young age.

To prevent obesity in childhood, families can:3

  • Promote healthy eating: Families can try swapping out processed snacks like potato chips for healthier snacks like baked cinnamon apple crisps. Saying no to soft drinks is another great starting point.

  • Get active together: Parents and children can both benefit from engaging in physical activity together. Make a tradition of physical activity, like playing frisbee or riding bikes together after school. Children ages 6 to 17 should get 60 minutes of physical activity per day.

  • Ensure consistent sleep: Children who don't get enough sleep have a greater risk of developing obesity, type 2 diabetes, and other health conditions. The amount of uninterrupted sleep your child needs depends on their age group, but the key is a consistent bedtime—even on weekends.

  • Minimize screen time: Too much screen time in childhood increases the risk of obesity, poor sleep, unhealthy eating, and more. Whenever possible, it's important to replace screen time with family time or physical activity. At a minimum, screens should be turned off at least one hour before bed.

If you are concerned about your child's weight, reach out to a healthcare provider. Your provider may be able to help you identify lifestyle factors that are contributing to your child's weight gain. They can also assess any health risks your child may have based on their weight or your family history.4

Diet to Prevent Obesity

Obesity can be prevented by following basic principles of healthy eating. Here are simple changes you can make to your eating habits that will help you lose weight and prevent obesity.

Eat More Fruits and Vegetables

Eating a diet rich in fruits and vegetables decreases the risk of obesity.5 Fruits and vegetables contain a variety of beneficial nutrients and are associated with a lower risk for diabetes and insulin resistance.6 They are also high in fiber, which keeps you feeling full with fewer calories and ensures your digestive system stays regulated.

Focus on filling your plate with whole vegetables and fruits at every meal. Aim for lots of natural colors—carrots, sweet potatoes, broccoli, bananas, eggplant—the more color, the merrier.

Go easy (or eliminate altogether) protein sources that are heavy in saturated fats, such as red meat and dairy. If you choose to cut out meat entirely, consult with a healthcare provider to ensure you are not at risk for nutritional deficiencies.6

Does a Plant-Based Diet Prevent Obesity?

Eating more plant foods and less animal foods lowers insulin resistance and contributes to a healthier BMI.6 Following a plant-based diet will not increase the risk of obesity. However, more research is needed to evaluate the benefits of plant-based diets for reducing obesity long-term.

Avoid Processed Foods

Highly processed foods, like white bread and many boxed snack foods, are a common source of empty calories, which tend to add up quickly. A 2019 study found that people who were offered a highly processed diet consumed more calories and gained weight, while those offered a minimally processed diet ate less and lost weight.7

There are many healthy alternatives to processed snacks that can be just as satisfying, such as:

  • Unsalted almonds, cashews, walnuts, and pistachios

  • Roasted chickpeas

  • Crispy lettuce wraps

  • Frozen yogurt covered blueberries

  • Baked banana chips

While it may take a little more time and creativity, planning and preparing healthy snacks can be an enjoyable and rewarding experience.

Limit Sugar and Artificial Sweeteners

It is important to keep your intake of added sugars low. According to current dietary guidelines, most adult women should have no more than 24 grams of sugar per day, while most adult men should have no more than 36.8

Major sources of added sugar to avoid include: 

  • Sugary beverages, including sodas and energy or sports drinks

  • Grain desserts like pies, cookies, and cakes

  • Fruit drinks (which are seldom 100% fruit juice)

  • Candy

  • Dairy desserts like ice cream

Artificial sweeteners have been linked to obesity and diabetes, too.9 While some natural sweeteners like agave do not raise glucose as fast as table sugar, they still raise blood sugar and should also be used in moderation.10

Reduce Saturated Fats

Numerous studies show that eating foods high in saturated fat contributes to obesity. Foods that are high in saturated fats include:11

  • Pizza

  • Cheese

  • Whole and reduced fat milk

  • Butter and dairy desserts

  • Meat products, such as sausage, bacon, beef, hamburgers

  • Cookies and other grain-based desserts

  • Many fast food dishes

Focus instead on sources of healthy fats (monounsaturated and polyunsaturated fats) like:

  • Avocados

  • Olive oil and canola oils

  • Tree nuts

  • Pumpkin and sesame seeds

  • Fish

Although these fats are healthier for you, they should still be limited to about 20% to 35% of daily calories.12 People with elevated cholesterol or vascular disease may need an even lower level.

Pay Attention to Beverages

A single, 12-ounce can of Coca-Cola contains 39 grams of sugar. That means one can of Coke alone exceeds the recommended daily intake of sugar.8

Sugar and calories in soft drinks, energy drinks, sports drinks, and juices quickly add up and may contribute to weight gain. But drinks marketed as "sugar-free" and "low-calorie" aren't much better. Artificially sweetened drinks also carry a risk of numerous health problems, including obesity.13

Rather than focusing on which artificial sweetener is best, it's better to avoid sweeteners in general. Make water or unsweetened drinks and your go-to instead.

Cook at Home

People who prepare meals at home are less likely to gain weight or develop type 2 diabetes, studies show.

One such study found that people who ate home cooked meals more than five times per week were 28% less likely to have an overweight BMI than people who ate home cooked meals less than three times per week. Eating more home cooked meals was also associated with having less body fat.14

Body Composition: Definition and Insights into Health

Exercising to Prevent Obesity

Most national and international guidelines recommend that the average adult get at least 150 minutes of moderate-intensity physical activity per week. That means at least 30 minutes per day, five days per week.15

Researchers have also found that people who walk at a brisk or fast pace are more likely to have a lower weight, lower body mass index (BMI), and lower waist circumference compared to individuals doing other activities.16 

In addition, experts recommend keeping active throughout the day, whether by using a standing desk, taking frequent stretch breaks, or finding ways to work in walking meetings throughout your day.

Reducing Stress to Prevent Obesity

Chronic stress raises levels of the stress hormone cortisol and leads to weight gain. It can also result in poor dietary choices, as cortisol and other stress hormones can increase “carb cravings” and make it difficult to exercise good judgment and willpower.17

Look into the many healthy ways to beat stress, and find what works best for you. This might include:

  • Going for a daily walk

  • Engaging in regular yoga or tai chi

  • Meditating

  • Listening to music you love

  • Getting together with friends

  • Journaling

Studies show having a pet can lower blood pressure.18 Additionally, pets, especially dogs, can increase your level of physical activity and help you stave off weight gain.19

Improving Sleep to Prevent Obesity

The role of sleep in overall well-being cannot be overstated. This extends to the goal of preventing obesity, too. The Centers for Disease Control and Prevention recommends seven or more hours of sleep for adults 18 and over and even more sleep for younger people.20

Studies have linked later bedtimes to weight gain over time. One of these studies included 137,000 people from 26 countries. It showed that, compared to people who go to bed before 10 p.m., people who go to bed after 10 have a 20% greater risk of general and abdominal obesity. Meanwhile, the risk is up to 38% higher in people who go to bed after 2 a.m.21

If you are having trouble falling asleep earlier, it may help to:22

  • Set a consistent bedtime.

  • Make sure your bedroom is quiet, dark, and a comfortable temperature.

  • Keep phones, computers, and televisions out of the bedroom.

  • Cut off screen time within one hour of going to bed.

  • Avoid large meals and caffeine before bedtime.

  • Increase physical exercise to help your body relax better at night.

How to Sleep Better by Forming New Habits

Summary

There are several possible contributors to obesity. The fact that the two biggest ones—diet and activity—are ones you can influence is good news. A healthy lifestyle that puts exercise and eating at its center can also bring myriad other health benefits. Getting good sleep and finding ways to reduce stress is important, too.

If you have made significant lifestyle changes and are still gaining weight or unable to lose weight, see a healthcare professional to rule out other possible causes of weight gain.