Diet myths

Myth 2: You don't need to exercise to lose weight

To maintain your body weight, the calories you take in should equal the calories you expend, so the most effective way to lose weight is by reducing calories and increasing exercise.

However, exercise is important even if you are not trying to lose weight, as it also improves cardiovascular health, circulation and decreases your risk of heart disease and diabetes.

Doctors have stated that it is better to be fit and slightly overweight than thin and unfit, as physical activity is as important as weight in preventing heart disease.

Myth 3: Drinking water helps you lose weight

Drinking water helps to keep you hydrated and fills you up without any calories, but it won't help you burn calories.

Water works well in combination with a sensible diet and regular exercise.

With high-fibre diets in particular, water can keep your gut healthy by helping to move things through your system more quickly.

Myth 4: A diet is successful only if you lose more than two pounds a week

Your main goal when trying to lose weight is to reduce fat rather than muscle.

But if you lose more than two pounds a week you'll also lose lean tissue (or muscle).

Because your basal metabolic rate (or the speed at which you burn calories) is determined by the amount of lean tissue you have, less muscle means your metabolism slows down and it becomes difficult to sustain weight-loss.

Myth 5: Reduce the foods you eat to lose weight

Diets based on a particular food or food type promise rapid weight-loss in a short period of time, but only work because they severely restrict calories.

These diets are unsustainable in the long-term and can lead to deficiencies since single foods don't contain the range of nutrients we need to stay healthy.

The Academy of General Dentistry in the US suggests that certain diets like this can even negatively affect oral health because they lack nutrients like calcium and vitamin D, which are necessary for maintaining healthy teeth and gums.

Myth 6: Fat is a four-letter word

Fat is not bad for you. In fact, it is important to get 35 per cent of your daily calories from fat (if you eat around 2000 calories a day, you'll need about 70g fat).

Fat has many crucial functions aside from being a concentrated source of energy. First, it circulates fat-soluble vitamins such as A, D, E and K through the blood so they can be absorbed by the body.

Secondly, fat contains essential fatty acids such omega-3 and omega-6, needed for the proper formation of the nerve walls.

Note: it's better to eat poly and mono-unsaturated fats (such as olive oil) which are good for your heart, than saturated fats (such as animal fats) which increase the risk of heart disease. Because fat is a concentrated source of energy, you don't need to eat a lot of it.

Myth 7: Potatoes and other carbs are fattening

Carbs such as potatoes, rice and pasta play an important role in diets since they satisfy our appetite without being too high in calories.

Fats have over twice the amount of calories per gram as carbs (9 calories per gram compared to 3.75 calories per gram respectively).

However, the type of carbohydrate you eat does count; choose whole wheat and wholegrain over white every time to keep your sugar levels on an even keel.

Myth 8: You can't have fat/alcohol/carbs if you're on a diet

The main goal of a diet is to eat fewer calories than you need to maintain your current body weight.

For most of us who want to lose weight permanently, we should follow a diet or eating plan that is nutritionally sound, tasty and not based on a single or limited range of foods such as the GI diet.

A realistic diet will not completely cut out whole food groups as this will only make you feel deprived. For many people, an eating plan that doesn't allow the occasional treat is a short-lived one.

Additionally, if you severely restrict your calories while dieting, then once you stop the diet you may be tempted to binge and put all the weight you lost back on again in double quick time.

Myth 9: Dairy is a no-no

Research shows that enjoying three servings of milk, cheese or yoghurt each day as part of a reduced-calorie weight-loss plan can give adults better results, than just cutting calories and consuming little or no dairy.