What makes us obese

Learn about childhood obesity, risk factors, classes, and more. Health Conditions Discover Plan Connect. Obesity is one of the biggest health problems in the world. Obesity and Willpower. Share on Pinterest. Summary Some people appear to be genetically susceptible to weight gain and obesity.

Engineered Junk Foods. Heavily processed foods are often little more than refined ingredients mixed with additives. Summary Stores are filled with processed foods that are hard to resist. These products also promote overeating. Food Addiction. Summary Some people experience strong food cravings or addiction.

This especially applies to sugar-sweetened, high-fat junk foods which stimulate the reward centers in the brain. Aggressive Marketing.

Junk food producers are very aggressive marketers. Insulin is a very important hormone that regulates energy storage, among other things. Summary High insulin levels and insulin resistance are linked to the development of obesity. To lower insulin levels, reduce your intake of refined carbs and eat more fiber. Certain Medications. Summary Some medications may promote weight gain by reducing the number of calories burned or increasing appetite. Leptin Resistance.

Leptin is another hormone that plays an important role in obesity. Food Availability. How can it be a matter of choice if there is none? Summary In some areas, finding fresh, whole foods may be difficult or expensive, leaving people no choice but to buy unhealthy junk foods. Added sugar may be the single worst aspect of the modern diet. For all these reasons, sugar contributes to increased energy storage and, ultimately, obesity.

Kids who drink sugary sodas and eat high-calorie, processed foods develop a taste for these products and continue eating them as adults, which tends to promote weight gain.

Likewise, kids who watch television and play video games instead of being active may be programming themselves for a sedentary future. Many features of modern life promote weight gain. In short, today's "obesogenic" environment encourages us to eat more and exercise less.

And there's growing evidence that broader aspects of the way we live — such as how much we sleep, our stress levels, and other psychological factors — can affect weight as well. Between and , the average man added calories to his daily fare, while the average woman added calories a day.

What's driving this trend? Experts say it's a combination of increased availability, bigger portions, and more high-calorie foods. Practically everywhere we go — shopping centers, sports stadiums, movie theaters — food is readily available. You can buy snacks or meals at roadside rest stops, hour convenience stores, even gyms and health clubs. In the s, fast-food restaurants offered one portion size.

Today, portion sizes have ballooned, a trend that has spilled over into many other foods, from cookies and popcorn to sandwiches and steaks. A typical serving of French fries from McDonald's contains three times more calories than when the franchise began. A single "super-sized" meal may contain 1,—2, calories — all the calories that most people need for an entire day. And research shows that people will often eat what's in front of them, even if they're already full.

Not surprisingly, we're also eating more high-calorie foods especially salty snacks, soft drinks, and pizza , which are much more readily available than lower-calorie choices like salads and whole fruits. Fat isn't necessarily the problem; in fact, research shows that the fat content of our diet has actually gone down since the early s. But many low-fat foods are very high in calories because they contain large amounts of sugar to improve their taste and palatability.

In fact, many low-fat foods are actually higher in calories than foods that are not low fat. The government's current recommendations for exercise call for an hour of moderate to vigorous exercise a day. Our daily lives don't offer many opportunities for activity. Children don't exercise as much in school, often because of cutbacks in physical education classes. Many people drive to work and spend much of the day sitting at a computer terminal.

Because we work long hours, we have trouble finding the time to go to the gym, play a sport, or exercise in other ways. Instead of walking to local shops and toting shopping bags, we drive to one-stop megastores, where we park close to the entrance, wheel our purchases in a shopping cart, and drive home.

The widespread use of vacuum cleaners, dishwashers, leaf blowers, and a host of other appliances takes nearly all the physical effort out of daily chores and can contribute as one of the causes of obesity. The average American watches about four hours of television per day, a habit that's been linked to overweight or obesity in a number of studies.

Data from the National Health and Nutrition Examination Survey, a long-term study monitoring the health of American adults, revealed that people with overweight and obesity spend more time watching television and playing video games than people of normal weight. Watching television more than two hours a day also raises the risk of overweight in children, even in those as young as three years old. Part of the problem may be that people are watching television instead of exercising or doing other activities that burn more calories watching TV burns only slightly more calories than sleeping, and less than other sedentary pursuits such as sewing or reading.

But food advertisements also may play a significant role. The average hour-long TV show features about 11 food and beverage commercials, which encourage people to eat.

And studies show that eating food in front of the TV stimulates people to eat more calories, and particularly more calories from fat. In fact, a study that limited the amount of TV kids watched demonstrated that this practice helped them lose weight — but not because they became more active when they weren't watching TV.

Similarly, you may not have been taught healthy ways of cooking, or you may not have access to healthier foods.

In addition, the people you spend time with may influence your weight — you're more likely to develop obesity if you have friends or relatives with obesity.

Obesity can occur at any age, even in young children. But as you age, hormonal changes and a less active lifestyle increase your risk of obesity. In addition, the amount of muscle in your body tends to decrease with age. Generally, lower muscle mass leads to a decrease in metabolism. These changes also reduce calorie needs and can make it harder to keep off excess weight.

If you don't consciously control what you eat and become more physically active as you age, you'll likely gain weight. Even if you have one or more of these risk factors, it doesn't mean that you're destined to develop obesity. You can counteract most risk factors through diet, physical activity and exercise, and behavior changes.

People with obesity are more likely to develop a number of potentially serious health problems, including:. Obesity can diminish the overall quality of life. You may not be able to do physical activities that you used to enjoy. You may avoid public places. People with obesity may even encounter discrimination.

Obesity care at Mayo Clinic. Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission. This content does not have an English version. This content does not have an Arabic version. Our obesity epidemic took off in the s, it follows, not simply because we started to eat more calories in the form of processed food, but because we began to replace the healthy fats in our diet with refined sugars and grains.

To appreciate how obesity researchers could have missed the hormonal connection to weight gain for so long, consider that refined sugars and grains, the same molecules that elevate insulin levels, also happen to be a source of calories.

The great mistake, according to proponents of the carbohydrate-insulin model, was blaming refined carbohydrates primarily for their energy content, their calories, rather than for their influence on our hormones. For the public, scientific debates about the nuances of obesity and the way our bodies store and access energy can seem like so much squabbling over minor points. But given the link between obesity and chronic disease, there may be no single question in American life more important than which side of this debate is correct.

If the carbohydrate-insulin model is correct — and its proponents acknowledge that we need more research before saying so with absolute certainty — it suggests a radically different approach to restoring health to the nearly three-quarters of American adults who are overweight. Instead of aiming to eat fewer calories, an approach that follows from the energy-balance model and that has failed for so many of us, we should replace the refined carbohydrates in our diets with healthy fats and protein without much concern for counting calories.

Such a high-fat, low-carbohydrate diet would lower insulin levels and allow our fat cells to release the calories they are hoarding. Whether the debate among scientists leads to a revolution in how we understand the science of getting fat remains to be seen.

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