Crash diets, fasting, or living on tiny amounts of food in order to lose weight, are not recommended by medical doctors. They can be dangerous, and present extreme health risks.
Crash Diets and Eating Disorders
Crash dieting is a type of food deprivation often seen in someone with an eating disorder. Anorexia sufferers starve themselves for long periods of time, while those with bulimia sometimes restrict their food intake to compensate for binge eating episodes.
Food restriction behaviour is not restricted to people with eating disorders, but it can be a slippery slope to acquiring an eating disorder.
The Effects of Extreme Dieting
Someone who is attempting to crash diet is likely to experience intense hunger, misery, depression, low energy and tiredness, and food cravings.
More serious health effects include impaired immunity, electrolyte imbalances, reduced red and white blood cell counts, organ failure (including liver, kidney and heart), and osteoporosis.
The irony is that although a crash dieter will be malnourished due to not getting enough vitamins and minerals and vital nutrients from food, food will consume their thoughts for much of the time.
Rapid weight loss is often seen during a food-restricting diet, and while this may be perceived as a positive thing, the reality is that water and muscle mass, as well as fat is being lost.
(Muscle is metabolically active (it burns calories) whereas fat is metabolically inactive.)
Weight Gain and Yo-yo Dieting
When a person returns to normal eating after a period of calorie restriction, they will inevitably gain weight as their body tries to replenish its fat reserves. The result will be a higher percentage of body fat than before.
And so begins the 'yo-yo' diet effect. People diet to lose weight, end up putting even more weight back on, and have to diet again. It's a vicious circle, and long-term, dieters can end up in a worse situation than in which they started.
Lose Weight the Healthy Way
For most people who want to lose weight, a diet which leaves them feeling starving all the time or any kind of diet designed to help them lose weight quickly is not the answer. They should seek professional advice from their doctor or nutritionist about healthy eating and safe exercise.
By losing weight safely and slowly, a person will stand a much better chance of maintaining his or her new weight.
If you don't have to starve yourself, then don't.