1. Yo-yo dieting can cause long-term damage to major organs, such as the kidney, liver, heart and muscles as well as hypertension.
  2. Dieting denies your body the essential food nutrients it needs, therefore it’s impossible to stay on a diet permanently without damaging your body.
  3. Constant dieting has been found to reduce the body’s natural killer cells. This means your immune system won’t function so well and this can increase your chances of getting cancer.
  4. Restricted diets result in the digestive system becoming unused to a variety of nutrients. As a result, digestive problems are far more likely.
  5. Dieting messes up your metabolic rate. Harsh diets slow down your metabolism and eventually bring about the rebound effect (where food intake makes you fatter than you were before you went on a diet!).*
  6. Miracle drugs are just as bad, and sometimes even dangerous (if in doubt, read the warnings and disclaimers they come with).
  7. Yo-yo dieting damages the skeleton. Each time you lose weight you lose bone density. This isn’t replaced when you regain the weight and the risk of osteoporosis (brittle bone disease) increases to dangerous levels.
  8. A single episode of sudden weight loss followed by rapid weight gain may actually increase your odds of developing heart disease so will actually do you more harm than good.
  9. The production of an important enzyme in fat production and storage increases when large amounts of weight are lost. The increased activity leads to more fat storage and makes continued weight loss very difficult. The faster the weight is lost, the more active the enzyme becomes.
  10. Other physical consequences of over-dieting include dry skin, headache, hair loss/discoloration, light-headedness, menstrual irregularities, sleepiness, gallstones, and constipation.

* Shirley described how this happened to her. ‘I’ve always dieted but each time I lose weight I put it back on eventually – plus a bit more each time. So now I’m actually bigger than I am usually before I diet. Each time I diet my default weight seems to go up slightly’.