Focus on fad dieting - Do fad diets really work?

Eulalee Thompson

High-protein diets are "very dangerous" and can have long-term effects especially in people who are at risk for diabetes and heart disease, warned Dr. Pauline Samuda, Caribbean Food and Nutrition Institute's (CFNI's) nutrition educator.

THE CONSTANT quest by many people to shed a few pounds here and there often leads them down the road of fad (or crash) dieting. It is a quest which the fad diet industry feeds into... happily.

But do fad diets really work? Dr. Pauline Samuda, Caribbean Food and Nutrition Institute's (CFNI's) nutrition educator said that if it sounds too good to be true, it probably is. No fad diet, she emphasised, has been proved to maintain weight loss for any period of time. Some of them are downright dangerous.

"Most fad diets can show a short-term, weight-reducing effect. This is mainly due to fluid loss from the body and once the individual returns to normal eating the weight is regained, sometimes more weight than was lost," Dr. Samuda said.

Cable television is exposing Jamaicans to many fad diets especially those used in North America. Here are examples of some of the more popular ones on the market, which Dr. Samuda was asked to comment on:

The cabbage soup diet ­ this diet is recommended for one week. One version of the cabbage soup has the following ingredients: cabbage, celery, green peppers, onions, tomatoes, V-8 juice, a packet of onion soup mix and water. On day 1, eat soup and any fruit excluding bananas; day 2, soup plus vegetables including a baked potato with butter for dinner; day 3, soup plus fruits and vegetables; day 4, up to eight bananas and skim milk, plus soup; day 5, six tomatoes and up to 20 ounces of beef, chicken or fish, plus soup; day 6, vegetables, chicken, fish or beef, plus soup and day 7, vegetables, brown rice, unsweetened fruit juice, plus soup.

The liquid diets ­ various brands of liquid diets are on the market, usually they are milk-based drinks used to replace one or two meals each day.

High-protein diets ­ the theory is that too much carbohydrates prevent the body from burning fat. These diets recommend eating unrestricted amounts of protein such as fish, chicken, fish, eggs and cheese but food items such as bread, pasta and foods with refined sugar are removed from the diet.

The grapefruit diet ­ grapefruit is believed by the proponents of this diet to contain a fat-burning enzyme. A typical day on this diet could be black coffee and one-half grapefruit for breakfast; for lunch, one-half grapefruit plus an egg, cucumber, toast and tea or coffee; and for dinner, a grapefruit, some lettuce, a tomato and coffee or tea.

The food-combining diet ­ this diet is based on the concept that fruits should not be eaten with starches and proteins and starches and proteins should not be eaten together. This diet might go like this­ for the first 10 days eat only fruits; then for the next week or so add one-half pound of bread, two tablespoons of butter and some corn; after that a complete protein can be added. Fatty treats are allowed on this diet.

Dr. Samuda says that the cabbage soup and liquid diets can be dangerous if used over an extended period. "These are very low-calorie, unbalanced diets and can have very dangerous effects on the health of the individual," she stressed.

High-protein diets are "very dangerous" and can have long-term effects especially in people who are at risk for diabetes and heart disease, Dr. Samuda said.

The grapefruit diet, she said is ridiculous, in fact, not to be mentioned.

The lure of fad diets is that they are simple and because they deprive the body of large amounts of calories, people do in fact lose weight in the short term. Nutritionists generally agree however, that starving the body of calories, triggers the metabolism into a slow-down mode where it actually begins to store energy.

Dr. Samuda also pointed out that fad diets tend to be low in certain minerals and can therefore lead to deficiency (iron) in the short term or osteoporosis (calcium deficiency) in the long term. She also said that these diets also tend to be low in certain minerals and vitamins and this can be potentially dangerous in specific circumstances, for example, during an injury, post-surgery or during pregnancy and lactation.

Fad diets, she said, also tend to have a nutrient imbalance (too much or one and too little of another) which can lead to metabolic changes in the body. "This can have both short-term and long-term effects, some of which can be very damaging, such as heart attacks and renal (kidney) failure," Dr. Samuda said.

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