Dieting is a global multi-billion dollar industry.
However, there is no evidence that people are getting thinner 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 is obese, and that number increases to 35% in the United States ( 1 , 2 ).
Interestingly, there is some evidence that weight loss diets don’t work in the long run and that they can actually lead to weight gain.
Diet 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 are not the only ones on a diet. Losing weight is a priority for many people who are underweight or slightly overweight, especially women.
Many researchers believe that this is related to having a bad body image aggravated by the constant exposure of the media to skinny models, celebrities and athletes ( 3 , 4 ).
The desire to be thinner can start as early as primary school. In one study, over 50% of underweight girls aged 6 to 8 years said that their ideal weight was less than their actual weight ( 5 ).
Girls’ beliefs about diet and weight are often learned from mothers.
In one study, 90% of mothers reported having recently dieted. The results of the study showed that the five-year-old daughters of dieting mothers were twice as likely to have thoughts about diet, compared to daughters of non-dieting mothers ( 6 ).
The desire to be thin is very common in women and can start as early as 5 years of age. Early awareness of the diet is usually due to the mother’s dietary behavior.
The billion dollar diet industry
Losing weight is big business worldwide.
In 2015, weight loss programs, products and other therapies were estimated to have generated more than $ 150 billion in profits in the United States and Europe combined ( 7 ).
The global weight loss market is forecast to reach $ 246 billion by 2022.
Not surprisingly, weight loss programs can be quite expensive for anyone who wants to lose more than a few pounds.
One study found that the average cost to lose 11 pounds. (5 kg) ranged from US $ 755 for the Weight Watchers program to US $ 2,730 for the drug orlistat ( 8 ).
What’s more, most people eat a lot of diets during their lifetime.
When these various attempts are taken into account, some people end up spending thousands of dollars in pursuit of weight loss, often without long-term success.
The diet industry generates billions of dollars each year and is expected to continue to grow in response to people’s desire to lose weight.
Weight loss diets success rates
How successful are weight loss diets in achieving long-term weight loss? Overall, the results are quite disappointing.
In one study, three years after participants completed a weight loss program, only 12% maintained at least 75% of the weight they lost, while 40% regained more weight than they originally lost ( 9 ).
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 the initial weight, on average ( 10 ).
However, another study found that only 19% of people were able to maintain a 10% weight loss for 5 years ( 11 ).
It also appears that weight recovery occurs regardless of the type of diet used for weight loss, although some diets are linked to less recovery than others.
For example, in a study comparing three diets, people who followed a diet rich in monounsaturated fat regained less weight than those who followed a low-fat or control diet ( 12 ).
A group of researchers who reviewed 14 weight loss studies pointed out that, in many cases, recovery may be greater than reported, because follow-up rates are very low and weights are usually reported by phone or mail ( 13 ) .
Research shows that most people will regain most of the weight they lose during the diet and will even end up weighing more than before.
Although a small percentage of people are able to lose weight and maintain it, most recover all or part of the weight they have lost and some recover even more.
Chronic diet and weight gain
Studies suggest that instead of achieving weight loss, most people who diet frequently end up gaining weight in the long run.
A 2013 review found that in 15 of the 20 studies of people who are not obese, recent dietary behavior predicted weight gain over time ( 14 ).
One factor that contributes to recovering people with less weight is the increase in appetite hormones.
The body increases its production of these hunger-inducing hormones when it feels that it has lost fat and muscle ( 15 ).
In addition, caloric restriction and loss of muscle mass can cause your body’s metabolism to slow down, making it easier to regain weight once you get back to your normal diet again.
In one study, when men with less weight followed a diet providing 50% of their caloric needs for 3 weeks, they started to burn 255 fewer calories per day ( 16 ).
Many women diet for the first time in their teens or teens.
There is much research showing that the diet during adolescence is associated with an increased risk of overweight, development of obesity or disorder in the future ( 17 ).
A 2003 study found that adolescents who were on a diet were twice as likely to be overweight as those who were not on a diet, regardless of their initial weight ( 18 ).
Although genetics play an important role in weight gain, studies with identical twins have shown that dietary behavior can be equally important ( 19 , 20 ).
In a study carried out in Finland, which followed 2,000 pairs of twins for 10 years, a twin who reported dieting once was twice as likely to gain weight as the non-dieting twin. In addition, the risk increased with additional attempts at dieting ( 20 ).
However, remember that these observational studies cannot prove that diet causes weight gain.
People who tend to gain weight are more likely to follow a diet, which may be the reason why the behavior of the diet is associated with an increased risk of gaining weight and developing obesity.
Instead of producing lasting weight loss, dieting among people who are not obese is associated with an increased risk of gaining weight and developing obesity over time.
Diet alternatives that really work
Fortunately, there are some alternatives to the diet that offer better chances of preventing or reversing weight gain.
Focus on healthy choices and conscious eating
Try to shift the focus from a diet mindset to eating in a way that optimizes your health.
To start, choose nutritious foods that keep you satisfied and allow you to maintain good energy levels so that you feel better.
Eating consciously is another useful strategy. Slowing down, enjoying the eating experience and listening to the signs of hunger and fullness in your body can improve your relationship with food and can lead to weight loss ( 21 , 22 , 23 ).
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 maintaining weight ( 24 , 25 ).
The best form of exercise is something you like and can commit to doing in the long run.
Accept that it is not possible to reach your “ideal” weight
The body mass index (BMI) is a measure of your weight in kilograms divided by the square of your height in meters. It is often used to help people determine their healthy weight range.
The researchers challenged the usefulness of BMI in predicting health risk, because it does not explain differences in bone structure, age, sex, muscle mass or where a person’s body fat is stored ( 26 ).
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 obesity.
However, it is important to recognize that you can be healthy, even if you are not at your ideal weight. Some people feel and perform better with a weight greater than what is considered a normal BMI.
While many diets promise to help you achieve your “dream body,” the truth is that some people are simply not cut to be too thin.
In fact, studies suggest that being in shape with a stable weight is healthier than losing and regaining weight through repeated diet cycles ( 27 , 28 , 29 ).
Accepting your current weight can lead to increased self-esteem and body confidence, in addition to avoiding life-long frustration at trying to achieve an unrealistic weight goal ( 30 , 31 ).
Try to focus on being healthier, rather than looking for an “ideal” weight. Let weight loss follow as a natural side effect of a healthy lifestyle.
The desire to lose weight usually starts early, especially among girls, and can lead to a chronic diet and restrictive eating patterns.
This can do more harm than good. Contrary to popular opinion, a permanent change in lifestyle is necessary.
Breaking the diet cycle can help you develop a better relationship with food and maintain a stable and healthy weight.