I’m a nutrition expert. The above is what I hope everyone knows about weight loss.

lose weight continues to dominate public discourse—often seen as a matter of personal responsibility. But after working in the health and wellness field for almost 15 years Nutrition Through my research, I discovered that weight is treated differently than almost every other health issue.

People are often blamed for their body shape, despite strong evidence that weight is determined by a complex combination of factors geneticsbiological, environmental and socioeconomic factors. Limited access to affordable, healthy food and lack of safe spaces exerciselong working hours and chronic stress – more common in poorer areas – can make maintaining a healthy weight more difficult.

Five things I wish more people knew about weight loss.

1. It goes against our biology

obesity Since the 1990s, the UK has considered it a national health priority and has introduced many policies in response. Yet obesity rates have not declined. This suggests that current approaches that tend to focus on individual responsibility are not working.

Even if weight loss methods are successful, the results are often not long-lasting. Research shows that most people who lose weight eventually gain it back, while obese people have a very low chance of reaching and maintaining a “normal” weight.

Part of the reason is that when we lose weight, our bodies fight back—a response rooted in our evolutionary history. This process is called metabolic adaptation: When we reduce energy intake and lose weight, our metabolism slows down and hunger hormones (like ghrelin) increase, encouraging us to eat more and regain the weight we’ve lost.

This biological response would make sense in our hunter-gatherer past, when feast and famine were common. But today, in a world where high-calorie, ultra-processed foods are cheap and readily available, these same survival traits make it easy to gain weight and difficult to lose.

So if you’ve been struggling to lose or maintain weight, it’s not a personal failure but a predictable physiological response.

2. It’s not about willpower

Some people seem to maintain a stable weight relatively easily, while others have difficulty. The difference isn’t just about willpower.

Weight is affected by many factors. Genetics play a big role—for example, influencing how quickly we burn calories, how hungry we feel, or how full we feel after a meal. Some people are naturally prone to feeling hungry or craving energy-dense foods, which can make losing weight more difficult.

Environmental and social factors also play a role. Having the time, money, or support to prepare healthy meals, stay active, and prioritize sleep can make a real difference—but not everyone has these resources.

When we ignore these complexities and view weight as purely a matter of self-control, we create stigma. This stigma can make people feel judged, shamed, or excluded, which ironically increases stress, lowers self-esteem, and makes healthy habits harder to develop.

3. Calories aren’t everything

Counting calories is often the default weight loss strategy. While in theory, creating a caloric deficit is essential for weight loss, in reality, it’s a lot more complicated.

First, calorie labels on foods are only estimates, and our own energy needs change from day to day. Even the energy we absorb from food can vary depending on how the food is cooked, digested, and the makeup of the bacteria in our gut.

There’s also a deeply held belief that “a calorie is just a calorie” – but our bodies don’t treat all calories equally. A cookie and a hard-boiled egg may contain similar calories, but they have very different effects on our hunger, digestion and energy levels. Cookies may cause a quick blood sugar spike and crash, while eggs provide longer-lasting satiety and nutritional value.

These misconceptions have fueled the rise of fad diets—like drinking only shakes or cutting out all foods. While they can achieve short-term weight loss by creating a caloric deficit, they are rarely sustainable and often lack essential nutrients.

A more realistic and balanced approach is to focus on long-term changes: eating more whole foods, taking out less, drinking less, and developing habits that support overall health.

4. Exercise is good for health, but it doesn’t necessarily lead to weight loss.

Many people believe that the more they exercise, the more weight they will lose. But science tells a more complex story.

Our bodies are very good at conserving energy. After a hard workout, we may unconsciously exercise less throughout the rest of the day, or feel hungrier and eat more – offsetting the calories burned.

In fact, research shows that total daily energy expenditure does not consistently increase with increased physical activity. Instead, the body adjusts by increasing efficiency and reducing energy expenditure elsewhere, making losing weight through exercise alone more difficult than many people expect.

Still, exercise has a range of benefits: It promotes cardiovascular health, improves mental health, preserves muscle mass, enhances metabolic function, strengthens bones and reduces the risk of chronic disease.

Even if the numbers on the scale don’t change, exercise remains one of the most powerful tools we have to improve our health and quality of life.

5. Improved health doesn’t always require weight loss

You don’t have to lose weight to become healthier.

While conscious weight loss can reduce the risk of diseases such as heart disease and certain cancers, research also shows that improving your diet and being more active can significantly improve health markers such as cholesterol, blood pressure, blood sugar, and insulin sensitivity, even if your weight remains the same.

About the author

So if you don’t see significant changes on the scale, it might be more helpful to shift your focus. Instead of chasing numbers, focus on behaviors: nourish your body, move regularly in a way you enjoy, get a good night’s sleep, and manage stress.

Weight is just one piece of the puzzle – health is about so much more.