Fit for Life is an alternative form of nutrition first published by the couple Harvey and Marilyn Diamond in 1985 in the book of the same name. The theories of the Fit for Life concept are based on the Natural Hygiene movement founded in the USA in the 19th century. On closer examination, the Fit-for-Life concept turns out to be a variant of Hay’s Food Combining Diet, supplemented by other dietary rules.
Principles and goals
The goal of Natural Hygiene teaching is to care for and maintain the health of the body as a whole. By providing people with the vital nature-given elements of air, water, food, sun, exercise, rest, sleep and love, the body’s self-cleansing, self-healing and self-maintaining powers are to be promoted in order to eliminate toxic “waste products” and thus also reduce weight. The Fit for Life principle is based mainly on four principles. The first principle is the principle of natural body cycles, according to which the body of:
- 12 to 20 ready to absorb food,
- 20 to 4 o’clock adjusted to the exploitation of the food component and
- 4 to 12 o’clock on the excretion of metabolic products (“slags”) is focused.
Particular attention is paid to the elimination phase between 4 and 12 o’clock, because a food intake in this phase to overload the body and eventually lead to obesity and disease. The so-called “energy ladder” is used to illustrate which foods should be consumed at what time of day. The second principle propagates as ideal food such, which contains 70% water. This is derived from the fact that the human body also consists of about 70% water. Water serves as a means of transporting nutrients and, more importantly, as a cleansing medium for detoxifying the body of “waste products.” Foods with high water content should therefore be the main component of the diet. The third principle regarding the right combination of foods is mainly based on the theories of Hay’s Food Combining Diet, according to which carbohydrates and proteins allegedly cannot be digested optimally when consumed at the same time. The resulting prolonged residence time of the food pulp in the gastrointestinal tract leads to fermentation and putrefaction processes. The fourth principle classifies humans as frugivores (fruit eaters). Fruits, vegetables and salads are especially recommended as so-called “sun food” or “living” food. However, fruit should not be eaten with other foods and only on an empty stomach, otherwise it would be prevented from passing into the intestines and cause them to ferment. Fruits and vegetables prevent hyperacidity of the body, as they can neutralize acids formed. The basic thesis of the Diamond couple is that the usual mixed diet pollutes the human body through the formation of “slags”. In addition, a “wrong diet” leads to toxemia (poisoning of the blood). Furthermore, humans are allegedly not adapted to the utilization of heated (“denatured”) foods, so that they cannot be completely digested. Moreover, since the “denatured” substances cannot be excreted, there is an excess in the body, which is the main cause of obesity. According to Diamonds, the incomplete utilization of food additionally leads to an “over-acidification” of the body, which the body tries to neutralize by storing water. This causes the body to become bloated, which in turn results in even greater obesity. Concentrated and processed foods with low water content such as bread, cereals, meat, dairy products and legumes are called “dead” foods. The consumption of meat is considered harmful to health. Milk and dairy products are rejected even more strictly because they lead to “sliminess” of the intestinal walls and mucous membranes, as well as being associated with allergies and, due to their highly acidifying effect, with the consumption of calcium. Based on the thesis that the minerals contained in water cannot be utilized and are deposited as “slags” in the arteries, for example, in combination with cholesterol, steam-distilled water is recommended as a beverage.
Principle of action
The Fit-for-Life concept contains many misleading and pseudoscientific statements as well as scientifically untenable or even false theses.
- There is no evidence for the existence of body cycles.
- Several studies in humans have shown that the consumption of a meal rich in carbohydrates and protein at the same time does not increase the passage time of the food pulp in the gastrointestinal tract (gastrointestinal tract) and does not lead in any other way to disturbances in the digestive process.
- A healthy body is able to keep its acid-base ratio in balance, so that it does not come to “overacidification” even with extremely unbalanced diet.
- There is no evidence that the digestion of fruit is affected by other food components.
- A “slag formation” is not medically detectable in the body. Absorbed food components are metabolized or excreted.
- Heated (“denatured”) foods are easier to digest and therefore even better digestible than raw food.
- Milk and dairy products, which are important suppliers of calcium, do not lead to mucus. In addition, about 85% of the population in Germany have the digestive enzyme lactase, which splits the carbohydrate lactose found in milk.
- Distilled water can affect the electrolyte balance of the body when consumed over a long period of time, as well as lead to the lack of minerals and trace elements.
- Minerals do not deposit in the arteries.
Implementation
Food selection
The main component of the diet should be foods with high water content, with preference given to raw foods. The ratio of water-rich foods such as fruits, vegetables and salads and “concentrated” foods such as cereal products, dairy products, meat, poultry, fish should be 70 to 30. Distilled water and freshly squeezed fruit and vegetable juices are the only approved beverages. Dairy products such as butter, yogurt, cream and cream cheese are recommended only unpasteurized. Honey should not be heated, oils should be cold pressed and not refined. Meat, milk, “denatured” foods and concentrated foods such as cereals, bread and legumes should be avoided. Mineral water, coffee, tea and alcohol are rejected.
Specifics
In the Fit-for-Life principle, the diet is adapted to the natural body cycles. Therefore, before 12 o’clock only fruit and fruit juice are allowed, at noon there are vegetables and salads and in the evening meat with salad or potatoes with vegetables. Carbohydrate-rich and protein-rich foods should not be combined within one meal. Fruit should only be eaten on an empty stomach. Foods with a high water content are preferred.
Nutritional assessment
Benefits
The Fit for Life concept is a diet high in fruits and vegetables.
Disadvantages
Separating carbohydrates and proteins within a meal can sometimes be difficult in practice. Nutritionally valuable legumes, which are high in carbohydrate and protein, should be avoided. Low consumption of grains and grain products, as well as milk and dairy products, can lead to deficiencies in B vitamins, vitamin D, calcium, magnesium, iron, and selenium. In addition, mineral deficiencies are also possible with the use of distilled water.
Conclusion
Fit for Life is in practice a predominantly vegetarian diet with a strong emphasis on raw foods. The concept is based on many false and misleading statements. In addition, it is partially contradictory. For example, meat, which according to Diamonds is harmful to health and should therefore be avoided, can be consumed daily according to the recommended diet plans. If the required food choices are followed, nutrition that meets needs is not possible, so micronutrient deficiencies can occur. The fit-for-life concept cannot be recommended as a permanent diet.
