Why is gradual weight loss better than a crash diet?

Crash diets (where someone tries to quickly lose weight by cutting down on the amount of calories they eat) don't work for long-term weight loss and most aren’t healthy. 

It’s best to lose weight gradually:

• at a rate of 0.5-1kg (1-2lbs) a week
• by eating a healthy, balanced diet combined with regular physical activity

At a rate of 0.5-1kg (1-2lb) a week you’re more likely to maintain a healthy weight long-term. For the best results, you need to combine your healthy diet with regular physical activity. For more information, see What weight loss plans are recommended?

Crash diets

Many diets:

• radically restrict your daily calorie intake, or
• miss out entire food groups

Diet plans like this are not recommended for weight loss and can make you feel unwell.

“Because they are nutritionally unbalanced, crash diets can lead to long-term poor health,” says dietitian Ursula Arens.

Depending on the type of diet, it may:

• slow down your metabolism: the rate at which your body turns food into energy
• prevent you from getting important nutrients and vitamins that your body needs to work properly
• reduce your intake of carbohydrates (such as pasta, bread, and rice) that are an essential source of energy
• increase your intake of protein and fat: too much saturated fat can raise your cholesterol and increase your risk of heart disease and stroke

Read more about the pros and cons of the top ten diets.

Fast weight loss

When you lessen the amount you eat, your body uses up energy stored in the liver and muscles. However, most of this initial weight loss will be water and muscle.

What’s more your body's response to dieting like this is to reduce the speed at which it burns off calories. This means you're actually slowing down your ability to lose weight.

Weight gain

People who crash diet by missing out food or greatly cutting down on their daily calories tend to put weight back on quicker than those who follow a long-term healthy diet plan.

Healthy balanced diet

Most diets are not healthy, and crash dieting for a long time can be harmful. Also, some are so restrictive that you may not have the willpower to stick to them.

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