Why Am I Not Losing Weight? Weight Loss Plateaus

When you begin your weight loss journey, you may notice the weight coming off quickly at first.

At some point in your weight loss journey, you’ll reach a point where your weight loss slows down or stops altogether. This is a completely normal part of the process and is a sign that you’ve reached a weight loss plateau.

Luckily, there are many things you can do to get your weight loss back on track and manage a weight loss plateau, and we’ll discuss them in more detail here.

A weight loss plateau put simply is when you stop losing weight or are losing weight at a much slower pace than you were before. It happens to everyone at some point in their weight loss journey, usually after a larger drop in weight at the start. It can also happen more than once.

Medically, it can often be explained by a slowing of your metabolism – meaning the things you were doing before to lose weight won’t cause the same results now. When you’re new to a weight loss programme that includes frequent exercising and healthy eating habits, your body is likely to lose weight quickly at first. However, over time our bodies adjust to this new way of eating and moving, and so a ‘weight loss plateau’ begins.

There are many reasons for this, for example, you could have simply been taking a day off your diet and calorie counting here and there. Or, it could be that your body has adapted and gotten fitter, meaning the same exercises as before aren’t burning as many calories.

There are many different reasons for a weight loss plateau, and they’re almost all down to how many calories you’re consuming and how your body burns these calories (metabolism). This can often be fixed by making a few small changes to your lifestyle and checking back in with your calorie counting, but there are other things to consider too.

Why does weight loss slow down?

Medically, weight loss plateaus can be explained by the way our bodies work. There are 3 main reasons for weight loss slowing down and while they can’t always be helped, you always have the power to make changes to get past them.

Fluid loss

Sudden drops at the start of a weight loss journey are common, and are often linked to fluid loss or ‘water weight’.

When you first start eating fewer calories, your body makes up the energy by releasing stored carbohydrates called glycogen. Each gram of glycogen is stored with at least 3 grams of water. So, as you use up glycogen, you’ll also use up the water – which is why this is called water weight.

Once your body has used up its carbohydrate stores, it will use stored fat for energy instead.

This isn’t to say you won’t lose fat within the first few weeks of your weight loss journey, only that a reason for such a big loss at the start can be linked to a loss of fluid.

Metabolism

Scientific evidence suggests that as we lose weight, our metabolism decreases. Metabolism or ‘metabolic rate’ is how much energy our body uses to power the chemical reactions needed to stay alive. Energy comes from the foods and drinks we eat, and also energy stores in the body like fat and glycogen. . A fast or high metabolism means you’ll burn more calories during activity and at rest, so it's easier to lose and maintain weight. This is also why some people can eat more food without gaining weight.

There are a number of theories behind metabolism and weight loss, which may explain why people get stuck in a plateau or find it more difficult to lose weight.

Adaptive thermogenesis

Adaptive thermogenesis is when your body adjusts how much energy it uses up by producing heat. When you’re losing weight and not getting as many calories as before, your body adapts to use less energy to make heat. These changes happen as your body tries to keep you safe, as it does not know if you’ll be able to get more calories again or if you’ll continue to lose weight. This was a handy survival mechanism in the past but can be unhelpful during a weight loss journey.

When adaptive thermogenesis kicks in, it causes a change in hormone levels. You might produce less leptin, which is an important hormone that sends signals to your brain to feel full. With less leptin, you will feel more hungry and want to eat more. The stress hormone cortisol may also increase, making it more difficult to stick to your diet and exercise plans.

The ‘set point’ theory

Another theory is called the ‘set point’ theory and is the idea that the body has a target weight range that it will try to maintain using hormones, your nervous system, metabolism, and even behaviour.

This theory suggests that once you reach a certain weight, your metabolism will slow down to maintain your ‘set point’, even if you’re still trying to lose weight.

Your appetite may also increase to help your body stay within the set point. Everyone has a different set point and this comes down to things like genetics, environment, and previous weight changes. Losing weight can become harder when set points are altered as they can change throughout our lives. For example during childbirth, or the menopause.

Set points can also alter if you develop diseases like:

• HIV
• gastrointestinal disorders - irritable bowel syndrome, inflammatory bowel disease
• endocrinological disorders - hyperthyroidism, diabetes, PCOS
• neuropsychiatric disorders - depression, anorexia, dementia

This may explain why some people get ‘stuck’ at a certain weight and cannot seem to get past it. This doesn’t mean you can’t lose weight past your set point, it’s just that you might need some additional support, such as using a weight loss medication and focusing on slow, steady weight loss.

Although our body may sometimes work against us when it comes to metabolism and weight loss, we are not stuck when this happens. You can work on boosting your metabolism in many ways, including weight training, exercising and moving regularly, eating protein to build muscle mass, and reducing stress levels.

A change in lifestyle

The third reason that weight loss slows down is because there’s been a change in your lifestyle. This usually means you’re not sticking to the same calorie deficit as you were before and might be explained by eating too many calories, not exercising enough, or not eating enough. We’ll discuss this in the next section.

What causes a weight loss plateau?

As we’ve discussed, there are lots of causes for a weight loss plateau.

A slowing metabolism

Weight loss can reduce your metabolism, which means the same things you were doing before may not work now and a change in diet or lifestyle may be needed to increase your metabolism so weight loss can continue.

Other reasons for a slowing metabolism can be:

• undereating – this may cause the body to go into conservation mode, which can slow down weight loss
• losing muscle mass – it takes more calories to maintain and build muscle than fat; muscle contributes to BMR (basal metabolic rate) which means losing muscles can reduce metabolic rate

Changes to your calorie intake

A calorie deficit is needed to lose weight. As you continue following your diet plan, it can become easier to be less strict with your calorie deficit, such as snacking more often or eating more calories.

You may also be inaccurately counting your calories, so your calorie intake has increased without you realising. Don’t forget to include all calories from drinks and snacks too.

Changes to your activity levels

Burning calories through exercise is a great way to keep up with your calorie deficit. Some reasons for a weight loss plateau could be:

• slowing down with your exercise routine
• not moving around as much as before
• gaining muscle mass - you could be losing fat but putting on muscle, so the scales may not change

Stress

It can be difficult to not put pressure on yourself when you’re trying to lose weight but stress could cause or make a weight loss plateau worse. Stress can contribute to a build-up of abdominal fat and increase appetite and food intake.

Sleep

Not getting enough good-quality sleep is linked to a decrease in weight loss and an increase in food intake, especially food containing carbohydrates and fat.

Health conditions and medications

Conditions like diabetes, which influences how your body uses insulin, can make it harder to lose weight. Although rare, you may have an undiagnosed health condition that’s stopping you from losing weight.

Certain medications can also impact weight loss or even cause weight gain, such as certain antidepressants, corticosteroids, and hormone replacement therapy (HRT). Speak with your doctor if you take a medicine that has weight gain or fluid retention as a side effect and you think it could be contributing to your weight loss plateau.

You might be in a weight loss plateau if:

• you’re losing weight at a considerably slower pace than you were before, such as 1 or 2 lbs every few weeks
• your weight loss has stopped altogether

Other signs to look out for include feeling more hungry or tired, as your metabolism may be slowing down.

Weight fluctuations vs a weight loss plateau

Weight fluctuations happen every day or every few days and it’s important to not get these mixed up with a weight loss plateau.

It’s common for your body weight to change between 1 to 2kg or 2.2 to 4.4lbs over a few days. These fluctuations are caused by many normal bodily processes and don’t necessarily indicate a fat increase. Because of this, you should stick to weighing yourself every 2 to 4 weeks, at the same time of day.

A weight loss plateau is when you’re only losing a small amount of weight every few weeks, or none at all. You may even start gaining weight again and this will be consistent for weeks.

Weight loss plateaus can last anywhere from a few weeks to a few months depending on what is causing your weight loss to slow down or stop. Even during a weight loss plateau, you can begin taking measures to shorten its duration.

You’re never stuck in a weight loss plateau, even if it feels like you are. There are always changes you can make to restart your weight loss journey, it just takes time, patience, and consistency.

It’s also important to know that as you lose weight and begin reaching a healthier body mass index (BMI), your weight loss will naturally decrease in speed. It’s best to stick to a slow, steady weight loss, like 1 to 2lbs a week.

Checking your diet and calorie intake

One common reason for a weight loss plateau is that your calorie intake has increased. The NHS recommends a calorie deficit of around 600 calories per day, so if you’re not sure how many calories you’re eating, this could be preventing you from losing weight. Track your calories and be strict with it, as this is the best way to ensure consistent weight loss.

What you eat is also very important, and you should be sticking to a healthy, balanced diet which includes:

• filling up on healthy sources of fibre and protein, which keep you fuller for longer
• getting enough protein, especially after strength training, as this can help build and maintain muscle
• reducing food portions
• not snacking, or eating healthier snacks and adding these to your daily calorie count
• limiting the amount of high-calorie foods in your diet, especially unhealthy fats and processed foods
• getting lots of fruits and vegetables in your diet

Following an exercise regime

Regular exercise can contribute to weight loss and keep you in a calorie deficit. You should be doing around 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity exercise every week if you’re between 19 and 64 years old. If you’re not doing enough exercise, this could be the reason for your weight loss plateau.

If you’re already doing enough exercise each week, there are a few other things that you focus on.

1. Regular strength training that works the major muscle groups is just as important as cardio. Gaining muscle will increase your metabolism so you burn more calories during exercise and at rest.
2. Doing different types of exercises – your body can get used to exercising pretty quickly, so you’ll need to change things up or do a few more reps to keep burning the same amount of calories as before.
3. Spreading exercise over at least 4 or 5 days per week, or every day.
4. Being more active in your everyday life, such as taking more walks, getting up more often if you spend a lot of time sitting down, or getting in small workouts throughout the day. Things like gardening or cleaning the house can all help with calorie burning and metabolism.

Working on your mentality

Weight loss can be mentally draining and reaching a weight loss plateau can cause many people to give up on their hard work. It’s important to take a step back from time to time and celebrate what you’ve achieved so far, and not just the number on the scales. You may have more energy, fit into clothes you couldn’t before, or just feel generally more confident and happier with your body.

A weight loss plateau isn’t the end of your weight loss journey and you do have the power to make changes. You can also speak with a doctor if you need further help and support with exercising or eating healthily. As stress can negatively affect your weight, we recommend finding coping mechanisms to reduce it, such as:

• getting enough sleep
• avoiding stress eating and getting help from friends, family, your GP, or a counsellor if stress makes it hard for you to continue losing weight
• exercising when you feel stressed, as this can trigger the release of feel-good endorphins as well as being good for you
• finding stress-busting activities that work for you, like yoga, meditation, walking, talking to someone, or taking part in a particular sport or hobby
• distracting yourself and doing something fun, such as an exercise class with your friends, reading a book, or listening to music

See your GP

If you’ve tried everything else and you still don’t seem to be losing weight after a few months, it’s best to get checked out. You can discuss what actions you’ve been taking with your doctor to see if there’s something in your lifestyle that could be causing your weight loss to stall. They may also check your medical history, as some conditions and medications make weight loss harder.

Your GP can also refer you to a weight management specialist or recommend a weight loss medication.

Do weight loss medications help with plateaus?

Yes, weight loss medications can help you if you struggle to lose weight through diet and exercise alone, especially if you’ve reached a weight loss plateau and can’t seem to get past a certain weight. There are 2 types of weight loss medications available: weight loss injections and weight loss tablets.

Weight loss injections

These work by reducing your appetite and delaying the emptying of food from your stomach, so you also feel full from less food. Weight loss injections can help massively when trying to maintain a calorie-controlled diet.

Weight loss injections available at ZAVA include:

• Mounjaro (tirzepatide) – people lose up to 22.5% of their weight in 72 weeks on the highest dose of 15mg, once per week
• Wegovy (semaglutide) – people lose up to 14.9% of their weight in 68 weeks on the highest dose of 2.4mg, once per week
• Liraglutide (generic Saxenda) – people lose up to 8% of their weight in 56 weeks on the highest dose of 3mg, once a day

Note: Saxenda is long-term out of stock. The generic version, Liraglutide is approved for weight loss treatment in the UK and will soon be available.

Weight loss tablets

These work in different ways depending on the active ingredient.

Orlistat reduces the amount of fat absorbed from your food, so around a third of the fat you eat is removed through your stool. This helps you lose weight as you’re taking in less fat. It helps around 37% of people lose 5% of their starting weight within 12 weeks.

Orlistat-based medications include:

• orlistat 120mg generic tablets
• Xenical 120mg branded tablets
• alli 60mg over-the-counter tablets (may be less effective as it’s only half the dose, but can be bought without a prescription)

Mysimba is another weight loss tablet that works on your brain to reduce cravings and hunger levels, so you’re less likely to snack or overeat. It helps people lose around 8.1% of their weight after 56 weeks on the highest dose of 2 tablets, twice a day.

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