Dieting myths

Most adults in the UK are living with overweight or obesity, which increases the risk of heart and circulatory diseases. But when you’re trying to reduce your weight, it can be hard to know what information to trust.

So, to help you find a balanced approach, we look at the truth behind 10 common diet and weight loss myths.

Healthier foods are more expensive

The increased cost of living has meant less money to spend, especially on food. But there are ways to buy healthier options without spending more money. You can:

• Buy frozen fruit and vegetables. They come ready to use and it’ll help you reduce waste. You can use only what you need and put the rest back in the freezer. It will last longer in the freezer than fresh products.
• Try cheaper or supermarket own brands. The value range is usually similar in taste to premium brands.
• Write a shopping list and stick to it. Planning each of your meals for the week can help you stop your shopping bill going up by adding things you don’t need like sugary treats.
• Use more pulses in your meals. Pulses (like beans, lentils, chickpeas and peas) are usually one of the cheapest supermarket items. They are low in fat and full of vitamins and fibre to keep you fuller for longer. They’ll also add flavour and texture to any tasty meal.
• Cook from scratch rather than eating ready-meals or takeaways. Making your own food at home is great way to make your food budget go further. You can make savings if you buy the loose fruit and vegetables instead of pre-packed ones. You can also control what goes in your meal to make it healthier.

Carbs are fattening

Carbohydrates (like bread, pasta, potatoes and rice) are part of a balanced diet. But choosing the right types and the right amount is the key to success. Carbs give your body:

• energy
• vitamins like iron, calcium and B vitamins
• fibre to support your digestion and help you feel fuller for longer.

Choosing high fibre starchy carbs and avoiding making high-fat additions helps. Like adding butter and cheese on your jacket potato or a creamy sauce on your pasta. Instead, you can:

• Top your jacket potato with flaky tuna or baked beans.
• Choose wholegrain bread, pasta, rice and breakfast cereals. They taste just as good and might help you feel fuller.
• Use a vegetable-based sauce for your pasta. A tomato sauce can taste just as good. And if you buy cans of chopped tomatoes, they’ll keep for longer in the cupboard than a cream sauce will in the fridge.

Intense exercise is the only way to lose weight

This isn’t true. The most effective way to lose weight is to reduce the number of calories we eat and drink. Exercise can support weight loss when we consume less calories.

Adults should get at least 150 minutes of moderate intensity activity every week, like walking and cycling. Or 75 minutes of intense activity every week, like playing sports such as football. If you’re exercising to lose excess weight, you may want to do more than this, and reduce your calorie intake.

Intense (or vigorous) exercise, like running and swimming, makes you breath hard and fast. It’s usually difficult to speak to someone without pausing during intense activities. Intense exercise isn’t suitable for everyone. If you have a medical condition, your doctor will be able to suggest types of activities and the intensity that’s safe for you.

Some moderate intensity exercises that can still help you be physically active are:

• dancing
• riding a bike
• washing a car
• water aerobics
• walking up and down stairs
• pushing a lawn mower or hoovering
• brisk walking with your dog or friends.

Being physically active can be fun too. It can be a way to connect with friends and family, like playing with a frisbee in the park after a picnic. Or a way to break up your schedule, like arranging a walk with your colleagues rather than sitting in a meeting room.

Regular exercise is good for your physical and mental health. It can improve your mood; make you feel more energised and help you sleep better. 

No snacks, no treats and restricted portions

Some diets are hard to stick to because they’re too restrictive. And the limited foods they allow can leave you lacking essential nutrients and feeling tired. This can make you crave foods high in fat and sugar. 

Crash diets, or fad diets, are a type of restrictive diet. They often require the person following the diet to eat a lot less calories than the recommended daily calorie intake for adults. They usually restrict whole food groups as well. Crash diets are not a safe way to lose weight. If you’re worried about your weight, your doctor, practise nurse or dietitian can advise you on the best diet and physical activities for you, to help you lose excess weight safely.

You might be surprised to know that having an occasional treat can make it easier to stick to a healthy balanced diet. And eating a healthy snack in between meals can reduce the temptation to eat foods high in fat and sugar. Some healthy snacks are:

• fresh fruit
• rice cakes
• unsalted nuts
• vegetables with a hummus dip.

Slimming pills and teas are safe and effective for weight loss

Many unprescribed weight loss products available to buy can contain ingredients that can be harmful to your health.

The most effective way to lose excess weight is to reduce the number of calories you eat and drink and be more physically active. Different approaches to doing this work for different people and you may have to experiment or try several times before you find what works for you. 

There are prescribed medicines for weight loss available from GP services. But they are not suitable for everyone. If you are worried about your weight, you can talk to your doctor at your local GP.

Skipping meals will keep the weight off

Skipping meals can make you lack essential nutrients and feel tired. If you miss meals like breakfast, you might feel tempted to eat foods high in fat and sugar when you feel hungry. This can mean you eat more calories than you need throughout the day.

Eating healthy balanced meals at regular times during the day can help you lose weight more successfully than if you skip meals.

‘Low fat’ foods are a healthy option

A lower fat option might not be better for you. Sometimes, the fat will be replaced with more sugar or salt to make it taste like the original product. This might not make the lower fat option healthier.

Even if your food’s packaging says it’s lower fat, you might want to check its nutrition label. You can check the amount of ‘total fat’ and the amount of ‘saturated fat’ (unhealthy fat) per serving on the label.

Drinking water helps you lose weight

Water doesn’t make you lose weight. But drinking water and staying hydrated is part of a balanced diet and can support your weight loss.

Sometimes, if you feel hungry you might actually be thirsty. If you’re tempted to snack, try drinking a glass of water first.

Water doesn’t have any calories or sugar so it’s a healthier option than sugary or caffeinated drinks. You can make water more exciting by adding:

• sweet, fresh berries
• a slice of fruit like lemon, lime, orange or apple
• fragrant herbs like fresh mint leaves, rosemary or a slice of ginger
• a herbal teabag like peppermint, camomile or jasmine in hot water.

Certain foods help you burn fat

There is very little evidence to prove that some foods and drinks can help you burn more fat. You may have heard this about:

• chilli
• green tea
• citrus fruits
• black coffee
• energy drinks.

Although certain foods and drinks might not burn more fat, eating a healthy balanced diet and physical activity can.

Eating after 8pm will make you gain weight

Gaining weight isn’t caused by the time you eat. If you don’t eat more than your recommended daily intake of calories, eating late won’t make you gain weight.

However, eating dinner earlier can also help your body digest your food properly. This can prevent you having indigestion before bedtime. It might also help you sleep better.

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Page last reviewed: October 2021
Next review due: October 2024