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Rating Alternative Diets for Seniors


Fit for Life for Seniors

This 1985 diet book by Harvey and Marilyn Diamond has sold millions of copies over the years and continues to be a popular volume, despite more than 15 years of scathing criticism from health experts.

Quick Take

  • Food-combining diet that dictates which foods should be eaten, in what combinations, and at which time of the day
  • Based on the theory that eating foods in the "wrong" combinations causes weight gain and illness
  • Deficient in several important nutrients

This Diet Is Best For

This diet is not recommended for anyone.

Who Should Not Try This Diet

This diet is not recommended for anyone.

The Premise

There are two basic tenets of this food-combining weight-loss diet: 1. It's not what you eat but when you eat and how you combine your food that determines weight loss and health. 2. Always eat fruit alone, never just before, just after, or with other foods.

Though those two themes are constant throughout the book, the Diamonds give many more dietary rules that must be followed in order to lose weight and be healthy. The book generally follows the food combination teachings of Herbert M. Shelton, a naturopath who developed the Natural Hygiene diet. According to Shelton's theory, the body experiences three digestive cycles during the day: appropriation, which is eating and digesting (noon to 8 p.m.), assimilation, which is absorption and use of nutrients (8 p.m. to 4 a.m.), and elimination of body wastes (4 a.m. to noon).

The Diamonds say that only by eating foods in the right combinations at the right times, following these natural cycles, can the body rid itself of toxins and excess weight. They also clearly suggest that following the program can fend off diseases related to aging, such as heart and kidney disease, stroke, diabetes, and other age-related conditions including balding and hearing loss.

The Rationale

The rationale behind Fit for Life is anything but rational. Among the nuggets of nutritional wisdom dispensed by the Diamonds are: Eating foods in the wrong combinations causes them to rot so they cannot be used by the body and they turn to fat; fruits and vegetables, because of their high water content, wash and cleanse the body of toxins, but if fruit is eaten at the end of a meal, it ferments and causes digestion and weight problems; all the nutrients the body needs are found in fruits and vegetables; eating combinations of foods, such as meat and potatoes or bread and cheese, causes obesity and disease; and toxic waste material is kept inside the body if there is not enough energy (through proper food combining) to excrete it. Improper food combining, they say, leads to many age-related diseases.

Eating on the Fit for Life Diet

If you follow the Diamonds' do's and don'ts, a typical day's menu calls for only fruit or fruit juice before noon, fruit and a salad for lunch, vegetables and either a starch or protein food for dinner, and fruit for a snack -- but only if you wait at least three hours after dinner.

Eggs and dairy products (except for unpasteurized butter, sour cream, whipping cream, white cheese, and yogurt) are all but forbidden. Simply put: Any food besides fruits and vegetables is considered a "concentrated food" (having a low water content) and these cannot be combined with one another; fruit must be eaten on an empty stomach.

What the Experts Say

Although Shelton died in 1985, the basics of his theories have been recycled and reinvented many times over by several diet book authors in addition to the Diamonds. Despite their broad appeal, these theories have been universally panned by experts as unscientific, ineffective, and potentially dangerous.

That's because they dictate a nutritionally unbalanced diet, recommend eating unpasteurized dairy products, and ignore potential negative physical reactions dieters might have to the eating plan. No scientific proof exists that this food-combining diet either prevents the buildup of harmful toxins or helps weight loss.

On the plus side, the Diamonds encourage dieters to eat lots of fruits and vegetables. Unfortunately, that's at the expense of other healthful foods. Though anyone who sticks with the Diamonds' program will likely lose weight, it's not because the food-combining diet rids the body of fat-causing toxins.

You lose weight on this diet because it's quite restrictive and low in calories. One analysis of the diet found it to be low in several nutrients that are important for seniors, including calcium, zinc, and vitamins B12 and D. Especially alarming is the fact that the Diamonds urge dieters to ignore signals that something could be wrong, such as diarrhea, dizziness, or headaches, which they attribute to the body ridding itself of toxins.

Calorie quota: Calories are not counted or restricted on the Diamond program. However, calorie intake is likely to be reduced because the emphasis is on fruits and vegetables, which are low in calories, and many foods are forbidden or severely restricted.

Yes: Lots of fruits and vegetables (but only if eaten in the right combination with other foods)

No: Combining different types of food, such as proteins and carbohydrate foods, or combining fruit with any other foods; dairy products (except butter); sugar; cooked eggs

Other similar diets: Suzanne Somers' Eat, Cheat, and Melt the Fat Away

The next page in this article discusses the Making the Case for Yourself for Seniors diet.

To learn more about senior health, see:


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