Do 'Diets' Really Just Make You Fatter?

Dieting is a multibillion-dollar global industry.

However, there’s no evidence people are becoming slimmer as a result.

In fact, the opposite seems to be true. Obesity has reached epidemic proportions worldwide.

About 13% of the world’s adult population has obesity, and this number increases to 35% in the United States (1, 2).

Interestingly, there’s some evidence that weight loss diets don’t work in the long term and may actually lead to weight gain.

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Dieting and body image

As the obesity epidemic continues to grow, many people turn to calorie-restricted diets in an attempt to lose weight.

However, people with obesity aren’t the only ones dieting. Losing weight is a priority for many people who either have less weight or are slightly overweight, particularly women.

Many researchers believe this is related to having a poor body image, which is made worse by constant media exposure to slim models, celebrities, and athletes (3, 4).

The desire to be thinner can begin as early as grade school. In one study, more than 50% of girls ages 6–8 with less weight said that their ideal weight was lower than their actual weight (5).

Girls’ beliefs about dieting and weight are often learned from their mothers.

In one study, 90% of mothers reported they had dieted recently. Study results showed 5-year-old daughters of dieting mothers were twice as likely to already have thoughts about dieting, compared with daughters of non-dieting mothers (6).

Summary

The desire to be thin is very common in women and can begin as early as 5 years old. Early awareness of dieting is often due to a mother’s dieting behavior.

The billion-dollar diet industry

Losing weight is big business worldwide.

In 2015, it was estimated that weight loss programs, products, and other therapies generated more than $150 billion in profits in the United States and Europe combined (7).

The global weight loss market is predicted to reach $246 billion by 2022 (8).

Not surprisingly, weight loss programs can be quite expensive for someone who wants to lose more than a few pounds.

One study found that the average cost to lose 11 pounds (5 kg) ranged from $755 for the Weight Watchers program to $2,730 for the medication orlistat (9).

What’s more, most people go on many diets during their lifetime.

When these multiple attempts are taken into consideration, some people end up spending thousands of dollars pursuing weight loss, often without long-term success.

Summary

The diet industry generates billions of dollars every year and is expected to continue to grow in response to people’s desire to lose weight.

Weight loss diets success rates

Unfortunately, weight loss diets have a disappointing track record.

In one study, 3 years after participants concluded a weight loss program, only 12% had kept off at least 75% of the weight they’d lost, while 40% had gained back more weight than they had originally lost (10).

Another study found that 5 years after a group of women lost weight during a 6-month weight loss program, they weighed 7.9 pounds (3.6 kg) more than their starting weight on average (11).

Yet, another study found that only 19% of people were able to maintain a 10% weight loss for 5 years (12).

It also appears that weight regain occurs regardless of the type of diet used for weight loss, although some diets are linked to less regain than others.

For instance, in a study comparing three diets, people who followed a diet high in monounsaturated fat regained less weight than those who followed a low fat or control diet (13).

A group of researchers who reviewed 14 weight loss studies pointed out that in many cases, regain may be higher than reported because follow-up rates are very low and weights are often self-reported by phone or mail (14).

Research shows that the majority of people will gain back most of the weight they lose while dieting and will even end up weighing more than before.

Summary

Although a small percentage of people manage to lose weight and keep it off, most people regain all or a portion of the weight they lost, and some gain back even more.

Chronic dieting and weight gain

Studies suggest that rather than achieving weight loss, most people who frequently diet end up gaining weight in the long term.

A 2013 review found that in 15 out of 20 studies of people without obesity, recent dieting behavior predicted weight gain over time (15).

One factor that contributes to regain in people with less weight is an increase in appetite hormones.

Your body boosts its production of these hunger-inducing hormones when it senses it has lost fat and muscle (16).

In addition, calorie restriction and loss of muscle mass may cause your body’s metabolism to slow down, making it easier to regain weight once you return to your usual eating pattern.

In one study, when men with less weight followed a diet providing 50% of their calorie needs for 3 weeks, they started burning 255 fewer calories each day (17).

Many women first go on a diet in their early teen or preteen years.

A lot of research shows that dieting during adolescence is associated with an increased risk of developing overweight, obesity, or disordered eating in the future (18).

A 2003 study found that teens who dieted were twice as likely to become overweight than non-dieting teens, regardless of their starting weight (19).

Although genetics play a large role in weight gain, studies on identical twins have shown that dieting behavior may be just as important (20, 21).

In a Finnish study that followed 2,000 sets of twins over 10 years, a twin who reported dieting even one time was twice as likely to gain weight compared with their non-dieting twin. Also, the risk increased with additional dieting attempts (21).

However, keep in mind that these observational studies don’t prove that dieting causes weight gain.

People who tend to gain weight are more likely to go on a diet, which may be the reason why dieting behavior is associated with an increased risk of gaining weight and developing obesity.

Summary

Rather than producing lasting weight loss, dieting among people who don’t have obesity is associated with an increased risk of gaining weight and developing obesity over time.

Alternatives to dieting that actually work

Fortunately, there are some alternatives to dieting that give you a better chance of avoiding or reversing weight gain.

Focus on healthy choices and mindful eating

Try shifting the focus from a dieting mentality to eating in a way that optimizes your health.

To start, choose nourishing foods that keep you satisfied and allow you to maintain good energy levels so you feel your best.

Eating mindfully is another helpful strategy. Slowing down, appreciating the eating experience, and listening to your body’s hunger and fullness cues can improve your relationship with food and may lead to weight loss (22, 23, 24).

Exercise regularly

Exercise can reduce stress and improve your overall health and sense of well-being.

Research suggests that at least 30 minutes of daily physical activity is particularly beneficial for weight maintenance (25, 26).

The best form of exercise is something you enjoy and can commit to doing long term.

Accept that achieving your ‘ideal’ weight may not be possible

Body mass index (BMI) is a measure of your weight in kilograms divided by the square of your height in meters. It’s often used to help people determine their healthy weight range.

Researchers have challenged the usefulness of BMI for predicting health risk, as it doesn’t account for differences in bone structure, age, gender, or muscle mass, or where a person’s body fat is stored (27).

A BMI between 18.5 and 24.9 is classified as normal, while a BMI between 25 and 29.9 is considered overweight, and a BMI above 30 refers to having obesity.

However, it’s important to recognize that you can be healthy even if you’re not at your ideal weight. Some people feel and perform best at a weight higher than what’s considered a normal BMI.

Although many diets promise to help you achieve your “dream body,” the truth is that some people simply aren’t cut out to be very thin.

Studies suggest that being fit at a stable weight is healthier than losing and regaining weight through repeated cycles of dieting (28, 29, 30).

Accepting your current weight can lead to increased self-esteem and body confidence, along with avoiding the lifelong frustration of trying to achieve an unrealistic weight goal (31, 32).

Summary

Try to focus on being healthier instead of aiming for an “ideal” weight. Let weight loss follow as a natural side effect of a healthy lifestyle.

The bottom line

The desire to be thin often begins early in life, particularly among girls, and it can lead to chronic dieting and restrictive eating patterns.

This can do more harm than good. Contrary to popular opinion, permanent changes in lifestyle habits are needed.

Breaking the dieting cycle can help you develop a better relationship with food and maintain a healthier stable weight.