Why am I not losing weight? 8 causes and what does work

8 reasons why you are not losing weight

People who get stuck usually aren't doing one thing wrong, but are up against three or four factors at once. In the Netherlands, 50.6% of adults are overweight and 15.7% have obesity, according to the Leefstijlmonitor (Lifestyle Monitor) by CBS (Statistics Netherlands) and RIVM (the National Institute for Public Health and the Environment) for 2025. Being overweight is therefore the rule rather than the exception.

1. You eat more calories than you think

On average, the number of calories people take in is significantly underestimated. Oils, sauces, a handful of nuts, the milk in your coffee and your children's leftovers all count, but rarely end up in your mental arithmetic. Weighing and recording everything for two weeks, without changing anything, gives a clear picture of your actual calorie intake.

2. You actually eat too little

Eating too little slows your weight loss rather than speeding it up. On a crash diet you lose muscle mass as well as fat, and muscles are precisely the tissue that burns energy. The result: you lose weight quickly for a few weeks, then it stalls, and as soon as you start eating normally you gain weight faster than before.

3. You exercise intensively, but sit still the rest of the day

Exercise does little to compensate if the other fifteen waking hours are spent sitting. An hour of exercise three times a week is healthy, but uses less energy than 8,000 steps a day, taking the stairs and getting up every hour. For many people, that everyday background movement is the biggest untapped gain.

4. You consistently sleep too little

Lack of sleep raises your hunger hormone and lowers your feeling of fullness. People who sleep too little demonstrably choose fast-acting carbohydrates more often the next day and keep eating later into the evening. When you are losing weight, seven to eight hours of sleep is not a luxury but part of the treatment.

5. You have been under stress for a long time

Chronic stress holds on to weight, especially around your belly. Under sustained pressure your cortisol rises, which stimulates fat storage around the organs and increases cravings for sugar and fat. On top of that, for many people food is the fastest way to feel a moment of calm, which only makes the pattern around willpower more stubborn.

6. Your hormones have changed

Hormonal changes shift where you store fat and how much energy you use. The menopause is the clearest example, but an underactive thyroid, PCOS or insulin resistance can also make losing weight considerably harder.

7. You take medicines or have a medical condition

Some commonly used medicines increase your weight as a side effect. Certain antidepressants, antipsychotics, corticosteroids, beta blockers and hormonal medicines can increase your appetite or change your fluid balance. These medicines are often necessary and you need to keep taking them, but they can make losing weight on your own very difficult. So never stop a medicine yourself; instead, discuss with your doctor whether there is an alternative and what support helps in your situation.

8. You expect a straight line down

Weight loss happens in steps, not in a straight line. Your weight fluctuates by one to two kilos a day because of fluid, salt, hormones and the contents of your intestines. So weigh yourself once a week at the same time and look at the trend over four weeks. That applies doubly to the phase of losing the last kilos, when the margin between intake and expenditure is smallest.

Lifestyle or medical: where is your brake?

I'm not losing weight despite diet and exercise

If you are doing everything right and nothing happens, something other than discipline is almost always going on. Three explanations are the most common. Your energy deficit is smaller than you think, because your intake has grown along with your training. You are building muscle while losing fat, so your clothes fit more loosely but your weight stays the same. Or your body has adapted to months of eating less.

In that case, don't just measure your weight. Your waist circumference, the fit of your clothes and a photo each month together tell you much more than the scales alone. If none of those show any change after eight weeks of consistent effort, it is time to look beyond diet and exercise.

Why won't my body lose weight? Your metabolism in energy-saving mode

When you lose weight, your body deliberately starts running more economically. This is called metabolic adaptation: you burn less energy at rest than you would expect based on your new weight, and at the same time your hunger increases. For your body this is not a fault but a survival mechanism.

How stubborn this is becomes clear from research that followed participants of a major weight loss programme for six years. After six years, their resting energy expenditure was on average more than 700 kilocalories per day below the starting point, while most of the weight they had lost had already returned. The researchers concluded that the adaptation is not temporary, but persists.

The same saving mode occurs when you lose weight with GLP-1 medication: your resting energy expenditure also falls and your body keeps defending its old weight. That is exactly why such a programme is medically supervised and why stopping without a plan is often followed by weight gain.

This explains why "just being a bit stricter" rarely works after a few months. You are then not fighting your habits, but a system that actively defends your weight. That is exactly where people who have already tried everything get stuck.

Hormones, stress and the menopause

For women over 45, it is not just the scales that change during the menopause, but also where fat is stored. Because oestrogen falls, fat storage shifts from the hips and buttocks to the belly. In research on the menopausal transition, fat burning fell by 32% in women who became postmenopausal, while this decline did not occur in women who had not yet reached the menopause. Energy expenditure during sleep also fell more sharply.

In other words: you are doing the same as ten years ago and yet you are gaining weight. That is not in your head and it is not a failure. What achieves most in this phase is strength training to maintain muscle mass, more protein and fibre, and realistic expectations. You can read more about this in our article on losing weight during the menopause.

Stress works along a similar route. Ongoing tension, poor sleep and emotional eating reinforce each other, and together they hold on to a weight that on paper should have fallen long ago.

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Medical causes: when should you see a doctor?

See a doctor if your weight doesn't go down despite a healthy lifestyle, or if your BMI is 30 or higher. At that threshold doctors speak of obesity, and overweight is then a medical condition that calls for treatment rather than yet another diet. Not sure where you stand? Calculate your BMI and take that figure with you to the appointment.

A doctor first looks at causes you cannot solve yourself: thyroid function, blood sugar and insulin resistance, hormonal changes, medication use, sleep apnoea and low mood. Exactly which conditions and medicines these are is set out in our overview of medical conditions that prevent weight loss.

If lifestyle turns out not to be enough, medical treatment is available. Medicines such as liraglutide (Saxenda), semaglutide (Wegovy) and tirzepatide (Mounjaro) act on your hunger and satiety, so you eat less without fighting it all day. According to the College ter Beoordeling van Geneesmiddelen (CBG, the Dutch Medicines Evaluation Board), they are available on prescription only and should always be used under a doctor's supervision. Side effects do occur, usually nausea, vomiting, constipation or diarrhoea, and they are precisely a reason why you need to be able to contact the doctor treating you quickly.

Not losing weight: what now?

Start by establishing where things get stuck, not with yet another diet. This order works best in practice.

1. Measure objectively for four weeks. Weight weekly, waist circumference monthly, and record everything you eat for one week.
2. Fix sleep and stress first. Without rest, nothing else gets off the ground.
3. Build muscle mass. Strength training twice a week and enough protein protect your metabolism while you lose weight.
4. Choose a deficit you can keep up for a year. Losing weight slowly gives a much lower chance of regaining it than losing weight quickly.
5. Have medical causes ruled out if nothing has changed after eight to twelve weeks.
6. Consider medical weight loss with a BMI of 30 or higher, or if you have already made several serious attempts.

This is how it works with us: first a consultation and intake with the doctor, then a prescription with home delivery if appropriate, and after that a follow-up every four weeks with that same doctor. Most people notice the first effects after about four weeks, mainly because the constant feeling of hunger decreases. Especially when it comes to side effects, quick and easy contact with your doctor is the most important thing a programme has to offer.

We are deliberately small-scale: we have supported around 50 people so far, with a 5.0 rating on Google from more than 20 reviews. We are not a budget clinic and don't intend to become one.

Do you recognise the energy-saving mode, the menopause or years of yo-yo dieting in your own story? One doctor of your own, personal contact every four weeks and your medication delivered to your home. Take the eligibility check →

Frequently asked questions about not losing weight

Why won't my body lose weight?

Your body defends its weight by lowering your metabolism and increasing your hunger as soon as you eat less. That adaptation can last for years. In addition, hormones, the menopause, medication, lack of sleep or a condition such as an underactive thyroid can slow weight loss.

What actually makes you lose weight?

A sustained energy deficit: consistently taking in less energy than you use. All diets that work ultimately do this, whether they are called low-carb, high-protein or time-restricted. What differs is how well you can keep it up, and that is mainly determined by satiety, habits and support.

What should you absolutely not eat if you want to lose weight?

There is no single product you are obliged to cut out. Liquid calories do make it unnecessarily hard, though: soft drinks, fruit juice, alcohol and speciality coffees provide a lot of energy without filling you up. The same goes for heavily processed snacks where you rarely stop at one portion.

What is the best way to lose 10 kilos?

Expect four to six months at a pace of half a kilo per week. That pace preserves muscle mass better and gives a lower chance of regaining weight than a crash diet. Combine a modest calorie deficit with strength training, enough protein and seven to eight hours of sleep. If it doesn't work after three months, have medical causes ruled out.

Not losing weight: should I see my GP?

Yes, see your GP (huisarts) if your BMI is 30 or higher, if you have symptoms such as extreme fatigue or severe menopausal symptoms, or if your weight doesn't go down despite a healthy lifestyle. The GP can do blood tests, review your medication and refer you to a dietitian or lifestyle programme.

Can I buy weight loss medication without a prescription?

No, weight loss medication requires a prescription and buying it online without one is prohibited in the Netherlands. The inspectorate warns about counterfeit injection pens with unknown contents or doses. If you go through a doctor and a registered pharmacy, you know what you are using and there is someone who assesses your side effects.