Popular diets

Diet books are rarely off the top ten best-sellers list and their appeal is understandable. They are frequently celebrity endorsed, promise a new and unique approach and often provide compelling accounts of personal success stories. The eating rules of popular diets are generally the most novel aspect of the diets, rather than their scientific basis, as is often claimed. The most popular diet books include:

 

  • Low carbohydrate diets e.g. Dr Atkins diet, radiant health, South Beach
  • Detox diets e.g. Carol Vordeman¬ís 28-day detox diet
  • Food combining diets e.g. The Hay diet
  • Blood type diet e.g. Dr Peter D¬íAdamo¬ís Eat Right For Your Type

In addition, diets which could be termed as ‘few foods’ diets (for example the cabbage soup diet or the grapefruit diet) are also popular.

The Atkins diet appears to prompt most enquiries from both patients and healthcare professionals. As yet, too few well-controlled studies exist to make a firm recommendation about the efficacy and long-term safety of the Atkins diet.4,5 However, the British Dietetic Association, the American Heart Association, and other professional health groups do not recommend it for the general public.

The mechanism by which high-protein diets induce rapid weight loss is in the main due to the diuretic effect of such diets.6 The nature of this diet is such that choice and variety are limited and, as protein is more satiating than carbohydrate and fat,7 it potentially limits the volume of food eaten. In addition, the novelty factor of such a diet is likely to aid compliance.

Vitamin and mineral supplements are required to ensure nutritional adequacy. A main concern is that the diet restricts fruit, vegetables and wholegrain foods, which have been shown to be protective to health when consumed regularly in the diet. Increased protein in the diet can lead to urinary calcium losses, raising concern about the risk of developing osteoporosis. The diet is not suitable for those with kidney disease or gout. Data from the respected Nurse Health Care Study also indicated that a high protein intake may increase the risk of developing kidney disease among those with mild renal insufficiency8, raising concern for the long-term implications of a diet such as the Atkins diet.

Many patients place a great deal of hope in a popular diet, leaving the practitioner unsure of what is best to advise. In addition, a practitioner may have observed other patients who have had success following a popular or fad diet plan. It seems wise to discuss with patients the likely benefits and disadvantages for them of using a novel diet in order to lose weight.

  • Prompt patients to ponder the ardent marketing of such diets
  • Share information about the reported side effects, and discuss the success and failure of other patients who may have tried this approach
  • Offer information about the level of scientific support for the claims of the diet and remember to explain clearly why the medical community exerts caution with anecdotal evidence
  • Remember to always discuss with the patient their long-term plans for maintaining weight loss

More information regarding popular diets can be found in the recently published ‘BBC Diet Trials’ book.9 The book also provides lots of sound advice and guidance for people who wish to lose weight and can be recommended to patients as part of a home-based weight loss programme.