The Okinawan islands in Japan are home to the world’s largest concentration of people over the age of 100. These centenarians follow an extremely healthy diet based on nutrient-dense foods such as green vegetables, sweet potatoes, fish, soy-based foods and whole grains. They eat very little, if any, meat, eggs or dairy products, and few sweets. Also notable is the fact that they eat 17 percent less food than the average Japanese and 40 percent fewer calories than the average American. While the type of food they eat certainly contributes to their longevity, the amount they eat is believed by many to be a central factor in their long life spans.
In the United States, the Okinawan diet has many followers, and now a small group of individuals has adopted a similar calorie-restrictive way of eating they believe is indeed the key to longer life. Sometimes referred to as followers of the CRON (Calorie Restriction for Optimal Nutrition) or CR diet, these dedicated souls eat 10–40 percent fewer calories than the national average. They eat a well-rounded, nutrient-rich diet, just less of it than most people. Their medical checkups are said to show that they are aging slower than an average American of the same age.
The CR diet developed from data compiled by bionaut Dr. Roy Walford during the scientific study Biosphere 2. The main objective is to create meals that combine nutrient-dense and calorie-lean foods in different ways, in the belief that the diet will activate a specific anti-aging gene. Calorie restriction is one of the few dietary disciplines that has been documented to increase both the median and maximum life span in a variety of animals, among them fish, rodents, dogs and non-human primates. Scientists who study calorie restriction and practitioners of the CR diet believe it may also be true for humans.
If you are interested in following a CR diet, it is very important to note that calorie restriction does not simply mean eating less, which can lead to malnutrition. It means getting the most out of what you put into your body. Lisa Walford, co-author of The Longevity Diet (Marlowe & Company, 2005) encourages us to “begin slowly; replace fatty and unhealthy foods with healthy ones, lots of vegetables and good sources of protein. Anyone practicing CR intelligently will recognize that every bite either nourishes and replenishes the body, or congests particular physiological systems and forces the body to work hard to overcome unhealthy fare.”
The Okinawan diet and the CR diet plan are not so different from one another. The concept of the Okinawan diet is limiting calorie intake by emphasizing high volume, high-nutrient foods with a low caloric density. Both diets emphasize eating green vegetables which are low in calories but high in nutrients, along with carbohydrates having a low glycemic index such as tofu, sweet potatoes, fruits, vegetables and whole grains like quinoa and barley. Low glycemic carbohydrates have numerous health benefits. They increase the body’s sensitivity to insulin, improve blood cholesterol levels and sustain energy while keeping dieters feeling full until the next meal.
The Okinawan diet advises eating miso soup before each meal so as to reduce the tendency to overeat. Many CR practitioners eat a “tease meal” before a regular meal to keep glucose levels low and to discourage overeating. The CR tease meal may consist of a small handful of walnuts, almonds, blueberries and cranberries, or half of a boiled sweet potato. Sweet potatoes are staples in both the Okinawan diet and the CR diet plan due to their high level of antioxidants.
Both diets advocate eating very small amounts of fish in order to benefit from omega-3 fatty acids. The CR diet plan suggests that your dietary fat should come from monosaturated fats found in olive oil, avocadoes and nuts. Nuts are also staples among Okinawans. Both diets advocate the elimination of simple sugars and flours because they provide very little nutritive value for the amount of calories they contain. They also have a high glycemic index which should be avoided whenever possible.
Ali Ronan, a fair-weather CR practitioner says, “The best advice I can give is to get some software that allows you to track what you are eating. This will give you information that you probably never knew about regarding what is going into your body. I would also recommend researching as much as you can about CR, dieting, healthy eating, exercise and other related topics. Having this information will be key in developing your own way of practicing CR. CR is not like Weight Watchers. The plan isn’t laid out for you, so you really have to step up and take an active approach to planning what you are eating, not just your calories, but your nutrients too.”
Before jumping headfirst into CR, you should consult your physician. Talk with your doctor about the plan and have some basic tests done to see where your body stands. Tests such as blood pressure, body weight, body temperature, complete blood cell count (CBC), a lipids panel, liver function panel and basic metabolic panel should be taken first to see whether your body is ready. If you are practicing CR to lose weight, it is absolutely necessary that you lose weight slowly. Losing weight rapidly can release toxins into the bloodstream, causing more harm than good. Your goal should be to lose one pound every two months until you reach your goal. For further information, visit www.crsociety.org.
(I wrote this article for Seattle Woman magazine’s Jan. 2010 issue.)