The human body requires a well-balanced diet, comprising adequate proportion of carbohydrates, proteins and fats. Essential vitamins and minerals are necessary in the right proportion. A healthy body and mind are a prerequisite for a healthy sex life.
Sex is a human need. People from all walks of life can have a good sex life. Size is no criteria for sex. Thus overweight people can have as good a sex life as thin people.
In fact, over-dieting may have its own adverse effects. Before indulging in self-starvation, it is better to consult the doctor or the dietician.
Instead of crash dieting, it is better to indulge in regular exercises under competent guidance.