Anti-aging diets are regimes that reduce the number of calories consumed by 30–50% while allowing the necessary amounts of vitamins, minerals, and other nutrients the body needs to sustain itself and grow. This calorie restriction has been shown to increase the lifespan of various animals, including rats, fish, fruit flies, dogs, and monkeys, by 30–50%. Some human studies have also been done—and longterm studies are underway— but evidence of its impact on humans is very limited compared to results available from the animal studies. The completed studies indicate that calorie restriction can increase the maximum human lifespan by about 30%. The problem preventing scientists from offering substantive proof that humans can greatly increase their lifespan by restricting calories is that the current maximum human lifespan is 110–120 years and full compliance with the diet is difficult. A 30% increase would extend the human lifespan to 143–156. This is an exceptionally long time for a scientific study and requires involvement of several generations of scientists. Only several hundred people have ever been documented to lived past age 110 and there are only two people with confirmed documentation who have lived to at least age 120: Jeanne Louise Calmet (1875–1997) of France who lived 122 years and 164 days; and Shigechiyo Izumi (1865–1986) of Japan who lived 120 years and 237 days, according to Guinness World Records.
Since 1980, dozens of books have been published offering specific calorie reduction diets aimed at increasing lifespan. The most popular diets include the Okinawa Diet, Anti-Inflammation Diet, Longevity Diet, Blood Type Diet, Anti-Aging Plan, and the 120-Year Diet.
Calorie restriction is a lifelong approach to eating by significantly lowering daily calorie intake while still getting all the body’s required nutrients. People who experience starvation or famine receive no longevity benefits since their low calorie intake contains little nutrition. The diet is believed to most benefit people who start in their mid-20s, with the beneficial effects decreasing proportionately with the age one begins the diet.
Although there are variations between anti-aging diets, most reduced calorie diets recommend a core set of foods. These include vegetables, fruits, fish, soy, low-fat or non-fat dairy products, nuts, avocados, and olive oil. The primary beverages recommended are water and green or black tea.
Guidelines on calorie reduction vary from diet to diet, ranging from a 10% reduction to a 50% reduction of normal intake. Roy L. Walford (1924–2004), author of several books on anti-aging diets, says a reasonable goal is to achieve a 10–25% reduction in a person’s normal weight based on age, height, and body frame. The Anti-Aging Plan diet recommends men of normal weight lose up to 18 % of their weight in the first six months of the diet. For a six-foot male weighing 175 lb, that means a loss of about 31 pounds. For a small-framed woman who is five-foot, six-inches tall and weighs 120 pounds, the plan recommends losing 10% of her weight in the first six months, a loss of 12 lb.
Walford’s Anti-Aging Plan is a diet based on decades of animal experimentation. It consists of computer generated food combinations and meal menus containing all of the U.S. Department of Agriculture’s Recommended Daily Allowances of vitamins and other essential nutrients using foods low in calories. On the diet, the maximum number of calories allowed is 1,800 per day. There are two methods for starting the diet: rapid orientation and gradual orientation.
The rapid orientation method allows people to eat low calorie meals rich in nutrients. This is a radical change for most people and requires a good deal of willpower. All foods low in nutrients are eliminated from the diet. The nutritional value and calories in Page 52 foods and meals is determined by a software program available for purchase from Walford’s Calorie Restriction Society.
The gradual orientation method allows people to adopt the diet over time. The first week, people eat a high-nutrient meal on one day. This increases by one meal a week until participants are eating one meal high in nutrients every day at the end of seven weeks. Other meals during the day are low-calorie, healthy foods but there is no limit on the amount a person can eat. After two months, participants switch to eating low-calorie, high-nutrition foods for all meals.
On his Web site (http://www.walford.com ), Walford states: “Going for longevity on the Anti-Aging Plan requires caloric limitation. We advise, however, that you view this as a lifestyle change and not a quick-fix program or a diet. Any person can physiologically adapt to this level of limitation and experience no physical hunger provided that nearly every calorie eaten is a nutrient-rich calorie.”
