Fast Weight Loss: Why it Doesn't Work

Fasting diets generate fast but false results. Here's why:

You lose fluid, not fat And any fluid lost will return as soon as the fast is completed, in other words you'll re-gain any weight that you lost.

Lowered metabolism During fasting your metabolism slows by up to 40% to prepare for starvation, so when you eat normally again your body burns fewer calories and you gain weight.

Hunger and lethargy Fasting leads to hunger and cravings - not what you need when you are trying to lose weight! And when you drastically cut your calorie intake you will feel weak, making it even more difficult to maintain your resolve to lose weight.

Yo yo dieting Fasting often leads to cycles of weight loss and weight gain called 'yo yo' dieting. 95% of people who go on fast weight loss diets regain any weight lost - plus more - within two years (1).

Abstinence leads to binging When your food intake is restricted you experience physical and emotional deprivation. This compels you to eat, which commonly leads to overeating or binging. As a result, you are likely to feel sensations of guilt and failure. This often becomes a cycle which is difficult to break and has devastating effects on your self esteem (1).

Nutritional deficiencies Prolonged fasting may lead to nutritional deficiencies. For example, if you don't consume enough calcium you may be at risk of osteoporosis, or if you don't consume enough fibre you may experience constipation.

Poor Health Fast weight loss is bad for your health because it:
- Increases your risk of medical complications such as gallstones, gout and constipation (2)
- Lowers your immunity
- Leaves you deficient in important vitamins and minerals.

Impracticalities Fast weight loss involves restricting food intake to the point where you are constantly hungry and lack the nutrients you need to maintain physical health and energy levels. This situation can't be sustained in the long term. Plus fasting makes it difficult to carry out normal social interactions - people who are dieting often avoid social situations and family mealtimes, leading to feelings of isolation and loneliness.

Some people claim that fasting can help rid your body of 'toxins' (i.e. the food you eat). 'Toxins' occur naturally in your body, and your body has fantastic systems to cleanse itself (your kidneys and liver).

Healthy Weight Loss

A sensible weight loss goal is 0.5 - 1kg per week, and the best way to achieve this is to make healthy changes to your eating and exercise habits. These changes should always be sustainable - that way you will lose weight and keep it off.

References:
1. Why Diets Don't Work, Eating Disorders Foundation of Victoria
2. Rapid Weight Loss Linked to Gallstones, Flinders Medical Centre