Good health and well-being are vital if we are to enjoy life to the full - and normally, we can expect to maintain our vitality through a balanced lifestyle which includes healthy food, plenty of exercise and lots of rest. However, there are times when our reserves run low - because of the stresses and strains of daily life, through lack of sleep and regular exercise, or because sometimes we may not eat a balanced diet which contains the vitamins, minerals and nutrients we need.