Updated 27 September 2013

How fast can you lose weight?

So is it okay to lose several kilograms a week, or should you rather take it slowly? A dietician comments.


An important aspect of weight loss is the rate at which the human body sheds unnecessary kilograms.

It's only human to want quick fixes and, thanks to the television and internet, we're used to instant gratification. But when it comes to the workings of the human body, we need to be more patient.

Most people don't gain large amounts of weight in a few days or weeks. It takes time to deposit those 10 extra kilograms on the tummy or hips. So, if you've gained the weight you want to lose over a period of years, it's unrealistic to think that you're going to shed the 10kg in a few brief weeks.

Research has shown that the most successful weight-loss programmes are the ones that allow us to lose weight at a rate of about 1kg per week.

If you steadily lose weight at the rate of 1kg per week, you'll not be stressing your body, and the chances of maintaining weight loss are so much greater.

Magic diets
There are many fad diets out there that promise fantastic weight-loss results in the fastest possible time.

But these diets don't help you to keep your weight down once you stop, because you can’t face another prune or fried egg! You'll regain all the weight you've lost and you may easily slip into the misery of yo-yo dieting - and that's something you should try to avoid at all costs.

Yo-yo dieting
Yo-yo dieting is the vicious cycle many people get trapped in when they try to lose weight by using fad, quick-fix diets. The person uses a fad diet and loses a large amount of weight in super-quick time.

As these diets are usually boring or highly unpalatable, the dieter decides to quit the diet and, within a short time, his or her weight has shot up again to previous levels, or (even more distressingly) to higher levels. What happens now, is that this person’s metabolism is suppressed and it becomes even more difficult to lose the excess weight.

If, on the other hand, you use a balanced, low-fat, high-fibre diet combined with plenty of exercise, your body will adjust to the weight loss. Once you've got rid of the excess kilograms, you'll not easily pick them up again.

By continuing with a low-fat diet and just increasing the portion sizes and keeping up with your exercise schedule, you're for all practical purposes guaranteed of not regaining the weight you've lost.

Overnight weight losses
Certain pills, which usually contain diuretics (this also applies to herbal products), will make you lose 1-2kg overnight. Wonderful news, you may think. But stop right there. You've lost water, which weighs about 1g per ml.

The moment you replenish the water supply in your body by drinking fluids (and this is essential if you're not to become dehydrated), you'll regain that weight. So don’t even bother to take such pills, because they're not making you lose fat and can have a negative effect on your kidneys, and/or cause dehydration.

Weigh yourself once a week
If you weigh yourself every day, you're just going to get stressed. Weight varies slightly from day to day, and even during a single day. For example, most people weigh less when they get up in the morning than at night.

To preserve your sanity when slimming, make it a golden rule to only weigh yourself once a week in the morning, wearing the same clothes each time.

- (Dr I.V. van Heerden, DietDoc, updated April 2011)

Any questions? Ask DietDoc


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