For anyone who has ever dieted to lose weight, weight regain is the most feared nightmare. Unfortunately, the very biology of those who lose weight predisposes them to weight regain, meaning that, despite their initial success, they are likely to regain the weight they lost. Fortunately, there are strategies that can help people fight against this tendency.
A widely held belief in the weight loss community, among trainers and their clients, is that if you lose more than 10% of your body weight, you will most likely regain it all within a year. For someone who has struggled to maintain their weight after a rigorous diet, this blunt statement is disheartening.
The bad news is that, unfortunately, this statement is true to some extent. Regaining weight after dieting is so common that it has its own nickname: the yo-yo diet, named after the famous children’s game. However, it is no laughing matter when the percentage of weight lost exceeds 10% and is lost not for the sake of fashion, but to combat obesity, one of the most insidious diseases of our time.
The good news is that, even though most people who diet to lose weight regain their original shape despite a well-thought-out and well-followed diet, a small number manage to break the pattern and keep the weight off for a year or longer.
One study states bluntly: “Substantial weight loss is possible across a range of treatment modalities, but long-term sustenance of lost weight is much more challenging, and weight regain is typical.”
A meta-analysis of 29 studies on long-term weight loss found that over half of the participants who lost weight regained it within two years, and 80% within five years. In other words, only around 20% of people who diet to substantially reduce their body weight are able to maintain their weight loss for at least one year.
However, other studies tone down the pessimism of “almost no one succeeds”, showing that the rate of desirable weight maintenance among obese patients in the United States may be higher than previously thought. This is supported by statistics from the National Weight Control Registry (NWCR), which has documented the success stories of thousands of members who lost an average of 33 kilograms and maintained their new weight for over five years. These cases challenge the notion that weight regain is inevitable, although achieving and maintaining the desired weight requires considerable effort to counteract the tendency to regain lost weight. But why is weight regain so widespread? What do those who manage not to regain the excess weight do differently?
Metabolic adaptation
As might be expected, biology has a powerful way of pushing people back to square one when it comes to weight. When we lose a significant percentage of our body weight, the body undergoes changes that increase the risk of weight regain. One such change is metabolic adaptation, or adaptive thermogenesis. After weight loss, the body becomes more efficient in terms of energy consumption. In other words, it burns fewer calories than would be expected for a body of its size. This mechanism helps the body protect itself from what it perceives as starvation. This is a natural strategy of the body, the management of which requires complex approaches.
A team of researchers who analysed long-term competitors in a US weight-loss show found that six years after losing a significant amount of weight, the participants’ resting metabolic rates were about 500 calories lower than expected for individuals with their body composition. In practical terms, this metabolic slowdown means that a person who has lost weight needs to eat significantly less than a person of the same height and weight who has never been obese in order to maintain their weight. Metabolic adaptation is a process that can take years, putting constant pressure on the individual to regain weight.
Hormonal changes
As well as a slower metabolism, people who have lost weight are affected by hormonal changes that occur after weight loss, leading to increased appetite and decreased satiety. Weight loss causes a sharp drop in leptin (the hormone that makes us feel full) and a significant increase in ghrelin and other hormones that make us feel hungry.
One study found that, even one year after a 10-week diet, participants had significantly lower levels of leptin and other satiety hormones and higher levels of ghrelin. They also reported feeling hungrier than before they started the weight loss process.
In short, after going on a weight-loss diet, our body predisposes us to hunger and makes us want to eat more than before. Unfortunately, these changes are not just short-term fluctuations; they persist in the long term, as if our entire body is conspiring to help us regain the lost weight.
The impact of increased appetite affects us more than the slowing of our metabolism. Researchers in the field estimate that for every kilogram of excess weight lost, the basal metabolic rate decreases by about 20–30 kcal/day and hunger increases, causing us to consume around 100 kcal/day more than before.
Over time, the imbalance between our increased desire to eat and our decreased metabolic need to do so will lead to regaining the excess weight.
Behavioural and lifestyle factors that work against us
While biology plays a role in our weight loss efforts, behavioural and environmental factors can also push us in a counterproductive direction. After losing weight through lifestyle changes (modifying diet and physical activity levels), many people return to their old eating habits or reduce their physical activity levels once their initial motivation wanes. This sets them on a path to regaining the weight.
Unfortunately, Western society is characterised as being “obesogenic”: processed foods that are high in calories and available in large portions are extremely accessible, while our lifestyles are becoming increasingly sedentary. It takes tremendous effort to swim against the tide. However, if healthy eating and regular exercise are not adopted permanently, weight regain is almost guaranteed.
Emotions
Psychological factors also play a role in long-term success. After the “honeymoon” phase of weight loss (when the reduction in weight is satisfying in itself), mental fatigue, loss of motivation, and a sense of personal loss and deprivation of tasty, enjoyable food set in. This can lead to “behavioural relapse”—a gradual return to unrestricted eating and a sedentary lifestyle. Those who experience emotional eating will also find it hard to maintain their desired weight, particularly during stressful periods.
At the opposite end of the spectrum, researchers say, are people who have established a certain way of thinking and a set of habits that help them. Those who manage to maintain their desired weight are most capable of regulating their emotions and have lower levels of “disinhibition” (i.e. they are less prone to compulsive overeating and binge eating). Those who fully enjoy the results of weight loss and cultivate the ability to focus on long-term goals are the winners in the battle with the scales.
The winner’s allies
The key to maintaining weight loss is twofold: the ability to resist biological impulses and behavioural consistency, as well as developing coping skills to help fight personal temptations, stress and environmental factors.
As with any other personal crisis, sustained support and accountability are extremely important factors for success. Many weight loss programmes are time-limited (e.g. a three-month diet), but people regain the weight once the nutritionist’s support is no longer available. Studies show that patients maintain their weight loss for longer if some form of formal intervention or post-diet follow-up is maintained. This is why experts recommend that any weight loss programme should include a maintenance phase with support for at least one year. In fact, some argue that weight loss programmes should focus on providing psychological support rather than on diet.
Strategies for maintaining your desired weight after a weight loss programme
Although there are real challenges for anyone who has lost a significant amount of weight, weight loss experts have identified strategies and habits that are strongly associated with successfully maintaining weight loss. The minority who succeed have several characteristics in common.
Consistent exercise is the most commonly reported strategy and involves approximately 60 minutes of moderate-intensity physical activity per day (such as brisk walking). As well as helping to burn calories and counteracting the slowing of metabolism to some extent, physical activity also helps to maintain cardiovascular health and a positive mood, which can indirectly support weight maintenance.
Maintaining a healthy, low-calorie, nutrient-rich diet is also associated with successful weight maintenance. A diet low in fat but high in fibre, fruit and vegetables is associated with success. Portion control is important to avoid overeating just because food is low in calories.
Sticking to a meal schedule and eating frequently also helps. Developing a meal routine and eating small, frequent meals can help to avoid the vicious cycle of extreme hunger and overeating.
Monitoring weight and food intake helps detect slip-ups early on so significant weight gain can be prevented. Keeping a food journal or using a food tracking app can make people more aware of their current status if they want to maintain their weight.
Managing psychological factors and expectations enables people to develop strategies to cope with cravings and stress by finding healthy alternatives to emotional eating. Those who are successful in maintaining their weight after losing it accept that plateaus are normal and stay motivated by focusing on their well-being rather than just their weight. Rather than seeing mistakes as failures, they view them as lessons to be learned.
Controlling the food environment is another key to success, achieved by planning meals and avoiding storing high-calorie foods at home. In order to maintain weight loss, it is necessary to plan healthy meals, avoid fast food and choose balanced, easily accessible snacks. Reducing exposure to temptations makes it easier to maintain healthy habits.
The miracle of maintenance
In the nutritionist’s office, I had a revelation when I heard the words, “Obesity is a chronic disease.” I knew, of course, that chronic diseases are not curable but can, at best, be properly managed so that patients can maintain their quality of life. Until then, I hadn’t associated this with my tendency to gain weight, although over the years I had sensed that my enjoyment of food probably had more to do with the emotional eating that many people complain about, for which there seems to be no permanent cure.
Two years after completing a weight-loss programme, during which I had lost 12% of my body weight (mostly fat), it felt as if I had blinked and woken up 6 kg heavier than when I first went to see the nutritionist.
For the first time in my short experience of dieting, but long history of blaming myself for gaining weight, I heard that “if you lose more than 10% of your body weight, you will put it all back on within a year.” Strangely, I felt understood. I hadn’t yet verified the accuracy of this statement or joined a support group, but I no longer felt alone. Me and my lack of willpower. Me and my unhealthy cravings for sweets. Me and my memories of fried food and high fat butter on white bread.
When science largely backed up that shocking statement, I felt motivated to go ahead with my plan to get my body back. As a woman, I have fought against my own biology many times before. Every month, I have to push through a thick emotional haze that dulls even the simplest pleasures as a result of premenstrual syndrome, an issue that affects so many women that it has become anecdotal. It is evident, therefore, that the preceding statements, rather than constituting an apology for biological determinism, are a tactical exposition of the adversary. This is what we are up against. And I believe that like any improbable (but not impossible) change, maintaining a healthy lifestyle—especially after losing weight—requires something of a miracle. I have witnessed miracles occur, and just as I believe education is one such miracle, I also believe the miracle of maintaining weight loss is possible.
As a process of relearning, maintaining weight loss is not linear—there are challenges—but if we view each obstacle as an opportunity to learn and improve our personal strategies, over time, new habits will become automatic and easier to maintain.
