Fit for Life
Fit for Life (FFL) is a diet and lifestyle book series stemming from the principles of Natural Hygiene. It is promoted mainly by the American writers Harvey and Marilyn Diamond. The Fit for Life book series recommends dietary principles including eating only fruit in the morning, eating predominantly "live" and "high-water-content" food, and if eating animal protein to avoid combining it with complex carbohydrates.
While the diet has been praised for encouraging the consumption of raw fruits and vegetables, several other aspects of the diet have been disputed by dietitians and nutritionists, and the American Dietetic Association and the American Academy of Family Physicians list it as a fad diet.
The diet is based on Diamond's exploration of Herbert M. Shelton theories of food combining. Both authors claimed to be able to bring about weight loss without the need to count calories or undertake anything more than a reasonable exercise program. In the first version of the program, Diamond claimed that if one eats the foods in the wrong combination they "cause fermentation" in the stomach. This in turns gives rise to the destruction of valuable enzymes & nutrients. Diamond categorized foods into two groups : "dead foods" that "clog" the body, and "living foods" that "cleanse" it. According to Fit for Life principles, dead foods are those that have highly refined or highly processed origins; while living foods are raw fruits and vegetables. The basic points of Fit for Life are as follows:
- Fruits are best eaten fresh and raw. Where possible they should be eaten alone.
- Carbohydrates & Proteins should never be combined in the one meal.
- Water dilutes stomach digestive juices and should never be drunk at meals.
- Dairy products are considered of limited value and due to their allergic capacity, should seldom, if ever, be eaten.
In the 2000s, the Fit for Life system added the Personalized FFL Weight Management Program, which employs proprietary protocols called Biochemical "Analyzation", Metabolic Typing and Genetic Predispositions. The Diamonds claim that these protocols allow the personalization of the diet, which thus customized is effective only for one individual, and can be used for that person's entire life. This version of the diet also puts less emphasis on "live" and "dead" foods, and instead talks of "enzyme deficient foods." The Diamonds posit that enzymes that digest proteins interfere with enzymes that digest carbohydrates, justifying some of the rules above. They also began to sell nutritional supplements, advertised as enzyme supplements, many of which are strongly recommended in the newest version of FFL.
Publications and marketing 
The diet came to public attention in the mid-1980s with the publication of Fit for Life, a New York Times best seller which sold millions of copies, over 12 million according to Harvey Diamond. Harvey Diamond has also appeared on dozens of television talk shows promoting his theories. In Fit for Life II (1989) the Diamonds warned against eating artificial food additives such as hydrogenated vegetable oil, which at the time was being promoted by the food industry as a healthy alternative to saturated fat. Tony Robbins promoted the Fit for Life principles and veganism to increase energy levels in his book Unlimited Power.
Book series 
- Fit for Life (1985) - by Harvey and Marilyn Diamond ISBN 0-446-30015-2
- Fit for Life II (1989) - by Harvey and Marilyn Diamond ISBN 0-446-35875-4
- Fit for Life: A New Beginning (2001) - by Harvey Diamond ISBN 1-57566-718-5
- Fit for Life Not Fat For Life (2003) - by Harvey Diamond ISBN 978-0-7573-0113-1
- Living Without Pain (2007) - by Harvey Diamond ISBN 0-9769961-0-3
Harvey Diamond's competence to write about nutrition has been contested because his doctoral degree came from the American College of Life Science, a non-accredited correspondence school founded in 1982 by T.C. Fry, a high-school dropout. FFL's personalized diet program has been criticized for providing a "Clinical Manual" that is heavily infused with alternative medicine claims about how the body works, which are scientifically inaccurate and not accepted by conventional medicine.
Despite the fact that FFL web site mentioned "clinical trials", the principles and benefits of FFL diet are not supported by scholarly research, and some of the claims have actually been directly refuted by scientific research. For example, a dissociated diet as that advertised by FFL is no more effective for weight loss than a calorie-restricted diet.
Financial controversy 
Bradenton, Florida, attorney Andre Perron filed civil suit in July 2009 against Diamond and his son, Beau, complaining that Beau operated a Ponzi scheme based on foreign currency exchanges (Forex), alleging the squandering $38 million of investors' money. Harvey Diamond has contended he has no connection with any wrongdoing, and that he himself has been a victim, having also lost money in this case.
See also 
- Tish Davidson (2007). "Fit for Life diet". In Jacqueline L. Longe. The Gale Encyclopedia of Diets: A Guide to Health and Nutrition. Thomson Gale. p. 383–385. ISBN 1-4144-2991-6.
- "BEST SELLERS". New York Times. 1986-01-05. Retrieved 2009-02-09.
- McDowell, Edwin (1988-01-06). "Best Sellers From 1987's Book Crop". New York Times. Retrieved 2009-02-09.
- Fein, Esther B. (1993-02-01). "THE MEDIA BUSINESS: Publishing; Where literary lightning hits, book houses often hope for a second strike". New York Times. Retrieved 2009-02-09.
- Diamond, Harvey (2003-11-17). Fit for life, not fat for life. HCI. p. 82. ISBN 978-0-7573-0113-1.
- Golay A, Allaz AF, Ybarra J, et al. (April 2000). "Similar weight loss with low-energy food combining or balanced diets". Int. J. Obes. Relat. Metab. Disord. 24 (4): 492–6. doi:10.1038/sj.ijo.0801185. PMID 10805507. Lay summary – WebMD (2009-02-09). Unknown parameter
- Harvey Diamond's official website
- Criticism by James J. Kenney, Ph.D., R.D.(written in 1986)
- ChaseFreedom's criticism by dietitian