Yo-yo dieting, also known as “weight cycling,” describes the pattern of losing weight, regaining it and then dieting again.
It’s a process that causes weight to go up and down like a yo-yo. This type of dieting is common — 10% of men and 30% of women have done it (1, 2).
This article will discuss some of the problems related to yo-yo dieting.
1. Increased Appetite Leads to More Weight Gain Over Time
During dieting, fat loss leads to decreased levels of the hormone leptin, which normally helps you feel full.
Under normal circumstances, your fat stores release leptin into the bloodstream. This tells the body that energy stores are available, and signals you to eat less.
As you lose fat, leptin decreases and appetite increases. This leads to increased appetite as the body tries to resupply depleted energy stores.
In addition, the loss of muscle mass during dieting causes the body to conserve energy (3).
When most people use a short-term diet to lose weight, they will regain 30–65% of that lost weight within one year (4).
Moreover, one in three dieters ends up heavier than before they dieted (3, 4).
This weight gain completes the “up” phase of yo-yo dieting, and may prompt dieters to begin another cycle of weight loss.
Summary: Losing weight causes the body to increase appetite and cling to its energy storage. As a result, some yo-yo dieters gain back more weight than they lost.
2. Higher Body Fat Percentage
In some studies, yo-yo dieting has led to an increased percentage of body fat.
During the weight gain phase of yo-yo dieting, fat is regained more easily than muscle mass. This can result in your body fat percentage increasing over multiple yo-yo cycles (5).
In one review, 11 out of 19 studies found that a history of yo-yo dieting predicted higher body fat percentage and greater belly fat (6).
This is more pronounced following a weight loss diet than with more subtle and sustainable lifestyle changes, and may be responsible for the yo-yo effect (3).
Summary: A majority of studies show yo-yo dieting leads to a higher body fat percentage. This can lead to other changes that make it harder to lose weight.
3. It Can Lead to Muscle Loss
During weight loss diets, the body loses muscle mass as well as body fat (7).
Because fat is regained more easily than muscle after weight loss, this can lead to more loss of muscle over time (6).
Muscle loss during dieting also leads to decreased physical strength (8).
These effects can be reduced with exercise, including strength training. Exercising signals the body to grow muscle, even when the rest of the body is slimming down (9).
During weight loss, the body’s dietary protein requirement also increases. Eating enough quality protein sources can help reduce muscle loss (10, 11, 12).
One study showed that when 114 adults took protein supplements as they were losing weight, they lost less muscle mass (13).
Summary: Weight loss can lead to muscle loss, and this can deplete your muscle mass over yo-yo dieting cycles. Exercise and eat quality protein sources to mitigate your muscle loss.
4. Weight Gain Leads to Fatty Liver
Fatty liver is when the body stores excess fat inside the liver cells.
Obesity is a risk factor for developing a fatty liver, and gaining weight puts you particularly at risk (14).
Fatty liver is associated with changes in the way the liver metabolizes fats and sugars, increasing the risk of type 2 diabetes.
It can also occasionally lead to chronic liver failure, also known as cirrhosis.
A study in mice showed that several cycles of weight gain and weight loss caused fatty liver (15).
Another mouse study showed that fatty liver led to liver damage in weight-cycling mice (16).
Summary: Weight gain leads to fatty liver, which can cause liver disease. In mice, this is exacerbated by weight cycling, though human studies are needed.
5. An Increased Risk of Diabetes
Yo-yo dieting is associated with a higher chance of developing type 2 diabetes, although not all studies found evidence for this.
A review of several studies showed that a history of yo-yo dieting predicted type 2 diabetes in four out of 17 studies (6).
A study of 15 adults showed that when participants regained weight after 28 days of weight loss, it was mostly belly fat (17).
Belly fat is more likely to lead to diabetes than fat stored in other locations, such as the arms, legs or hips (18).
One study showed increased insulin levels in rats that went through 12 months of weight cycling, compared to those that gained weight consistently (19).
Increased insulin levels like these can be an early sign of diabetes.
Although diabetes has not been seen in all human studies of yo-yo dieting, it is probably most increased in people who end up at a higher weight than before their diet (6).
Summary: In a few studies, yo-yo dieting increased the risk of diabetes. The risk is greatest in those who end up at a higher weight than before their diet.
6. An Increased Risk of Heart Disease
Weight cycling has been associated with coronary artery disease, a condition in which the arteries that supply the heart become narrow (20).
Weight gain, even more than being overweight, increases the risk of heart disease (21).
According to a study of 9,509 adults, the increase in the risk of heart disease depends on the size of the swing in weight — the more weight lost and regained during yo-yo dieting, the greater the risk (22).
One review of several studies concluded that large variations in weight over time doubled the odds of death from heart disease (23).
Summary: The risk of heart disease increases with weight gain and fluctuating weight. The greater the change in weight, the greater the risk.
7. It Can Increase Blood Pressure
Weight gain, including rebound or yo-yo weight gain after dieting, is also linked to increased blood pressure.
Making matters worse, yo-yo dieting may blunt the healthy effect of weight loss on blood pressure in the future.
A study of 66 adults found that those with a history of yo-yo dieting had less improvement in blood pressure while losing weight (24).
A longer-term study found that this effect may fade after 15 years, suggesting that weight cycling during youth may not affect the risk of heart disease in middle age or later (25).
A third, long-term study also found the harmful associations of prior yo-yo dieting were strongest when yo-yo dieting had occurred more recently, rather than decades prior (26).
Summary: Weight gain, including rebound weight gain in yo-yo dieting, increases blood pressure. This effect can linger for years, but appears to fade over time.
8. It Can Cause Frustration
It can be very frustrating to see the hard work you put into losing weight vanish during the rebound weight gain of yo-yo dieting.
In fact, adults with a history of yo-yo dieting report feeling dissatisfied with their lives and health (20).
Yo-yo dieters also report poor self-efficacy regarding their body and health. In other words, they feel a sense of being out of control (27).
However, yo-yo dieting does not appear to be related to depression, self-restraint or negative personality traits (27).
This distinction is important. If you have had trouble with yo-yo dieting in the past, do not allow yourself to feel defeated, hopeless or guilty.
You may have tried some diets that didn’t help you achieve the long-term results you wanted. This is not a personal failure — it’s simply a reason to try something else.
Summary: Yo-yo dieting can make you feel out of control, but it’s not a sign of personal weakness. If you haven’t found the long-term health changes you’re after with dieting, it’s time to try something else.
9. It May Be Worse Than Staying Overweight
Losing weight if you’re overweight improves your heart health, reduces your risk of diabetes and boosts your physical fitness (28).
Losing weight can also reverse fatty liver, improve sleep, reduce the risk of cancer, improve mood and extend the length and quality of your life (29).
In contrast, weight gain leads to the opposite of all these benefits (30).
Yo-yo dieting is somewhere in between. It’s not as harmful as gaining weight, but it is definitely worse than losing weight and keeping it off (21).
It’s controversial whether yo-yo dieting is worse for you than maintaining a steady weight, and not all studies agree (6, 31, 32).
One of the larger studies available followed 505 men aged 55–74 for 15 years.
Their weight fluctuations were associated with an 80% higher risk of dying during the study period. Meanwhile, obese men who maintained a consistent weight had a risk of dying that was similar to normal-weight men (33).
One difficulty with this research is that researchers don’t always know why the participants were weight cycling, and changes in weight may be related to some other medical condition that shortened their lifespans (34).
Summary: It’s unclear from the available research whether it’s better to yo-yo or stay overweight. What is clear is that making small, permanent healthy lifestyle changes is the best option.
10. Short-Term Thinking Prevents Long-Term Lifestyle Changes
Most diets prescribe a set of rules to follow for a set period of time, usually to meet a weight loss goal or other health goal.
This kind of diet sets you up to fail, because it teaches you that the rules need to be followed until your goal is met.
Once you finish the diet, it is easy to slip back into the habits that caused weight gain to begin with.
Because the body increases appetite and holds on to fat stores during dieting, all too often a temporary diet becomes self-defeating, leading to temporary improvement followed by weight gain and disappointment (3).
To break the cycle of temporary changes producing temporary success, stop thinking in terms of a diet and start thinking in terms of a lifestyle.
A large study of more than 120,000 adults in the United States found that several habits could help gradually decrease and maintain weight over several years (35).
Here are some of the behaviors it found worked for long-term weight loss:
- Eating healthy foods: Such as yogurt, fruits, vegetables and tree nuts (not peanuts).
- Avoiding junk foods: Such as potato chips and sugary beverages.
- Limiting starchy foods: Using starchy foods like potatoes in moderation.
- Exercising: Find something active that you enjoy doing.
- Getting good sleep: Get 6–8 hours of sleep each night.
- Limiting television viewing: Limit your TV time or exercise while you watch.
By making permanent lifestyle changes that promote a healthy weight, you can have permanent success and break the yo-yo cycle.
Importantly, a study of 439 overweight women showed that a lifestyle intervention designed to promote gradual and consistent weight loss over time was equally effective in women with or without a history of yo-yo dieting (36).
This is encouraging, showing that even if you may have had difficulty keeping weight off in the past, making long-term lifestyle changes can still help you lose weight.
Summary: Yo-yo dieting is a cycle of temporary changes producing temporary results. To break the cycle, start thinking in terms of permanent lifestyle changes.
The Bottom Line
Yo-yo dieting is a cycle of short-term changes in eating and activity. For those reasons, it leads to only short-term benefits.
After losing weight, appetite increases and your body hangs on to fat. This leads to weight gain, and many dieters end up back where they started or worse.
Yo-yo dieting can increase your body fat percent at the expense of muscle mass and strength, and can cause fatty liver, high blood pressure, diabetes and heart disease.
To break the frustrating cycle, make small, permanent lifestyle changes instead.
These kinds of changes will prolong and improve your life, even if your weight loss is slow or small.