(Anyone can do it)
Seventy years of scientific research shows that restricting calories to 30% below normal intake can extend life span by up to 50% in laboratory animals. New research shows that calorie restriction may extend the life span of human beings as well.
Bottom Line/Personal interviewed Paul McGlothin and Meredith Averill, internationally recognized experts on calorie restriction and authors of The CR Way: Using the Secrets of Calorie Restriction for a Longer, Healthier Life. Here, some of their important findings…
Reporting in Science in 2009, researchers from the University of Wisconsin revealed the results of a study on calorie restriction in rhesus monkeys, our closest “relatives.” The researchers studied 76 adult rhesus monkeys (which live an average of 27 years and a maximum of 40), dividing them into two groups. One group ate a calorie-restricted diet, and one didn’t. After 20 years, 37% of the monkeys in the nonrestricted group had died, compared with only 13% in the calorie-restricted group. The calorie-restricted monkeys also had fewer incidences of heart disease, diabetes, cancer and brain disease.
In research published in 2007, scientists at Washington University School of Medicine in St. Louis studied the biomarkers of aging of 33 people, average age 51, who ate a calorie-restricted diet for an average of six years. Compared with another group of people who ate a typical American diet, the calorie-restricted practitioners had lab results that are typical of people much younger than themselves. They had lower cholesterol, lower blood pressure, less body fat and lower glucose (blood sugar) levels.
The study participants also had lower levels of insulin (the hormone that regulates blood sugar)… C-reactive protein (a biomarker for disease-causing inflammation)… tumor necrosis factor (a biomarker for an overactive immune system)… and thyroid hormone T3 (lower levels indicate a slower, cell-preserving metabolic rate).
WHY IT WORKS
There are several theories as to why calorie restriction improves health and may increase life span. It may…
EASY WAY TO CUT BACK
The level of calorie restriction probably required to extend life in humans — about 20% to 30% of typical intake — is more than most people are willing to do on a regular basis, but reducing calories by even 5% can produce significant health benefits.
Estimated calorie requirements for a moderately active person age 51 or older are 2,200 to 2,400 calories a day for a man and 1,800 for a woman. Reducing calories by 5% would mean cutting between 110 and 120 daily calories for a man and 90 for a woman.
With just a few changes in your dietary routine, you easily can reduce calories by 5% or more and improve your health…
Animal protein: Salmon (Alaskan wild, canned, fresh or frozen), sardines, tuna.
Good fats: Nuts…avocados… grapeseed oil, extra-virgin olive oil.
Beans: Adzuki, limas, black-eyed peas, black turtle beans, garbanzos (chickpeas), lentils (red or green), mung, pinto, soy.
Veggies: Arugula, beets, bok choy, broccoli, cabbage, carrots, chard, collard greens, garlic, kale, kohlrabi, leeks, mushrooms (maitake, portobello, shiitake), mustard greens, onions, romaine lettuce, spinach, squash (butternut, summer), sweet potatoes, tomatoes.
Grains: Barley, quinoa, wild rice, sprouted-grain breads.
Fruit: Apricots, blackberries, blueberries, cantaloupe, cranberries, kiwi, lemons, limes, oranges, peaches, raspberries, strawberries, tangerines.
Spices and herbs: Season foods with herbs and spices rather than salt, butter or sugar. Examples include basil, chives, ginger, parsley and turmeric.
The best way to regulate glucose and insulin is to choose carbohydrates with a low-to-moderate score on the Glycemic Index (GI) — carbohydrates that digest slowly so that glucose and insulin levels don’t suddenly skyrocket.
The beans, veggies, grains and fruits that are nutrient-dense have low-to-moderate GIs.
Other ways to keep glucose low…
Start your meal with one cup of water with one tablespoon of lemon juice, which lowers glucose.
Finish your last meal of the day as early as possible, eating complex carbohydrates and a fat source.
After your evening meal, take a 45-minute or longer walk.
Each day, eat 0.36 grams of protein per pound of body weight — at your healthiest, ideal body weight. That’s 43 grams of protein a day for a woman whose ideal weight is 120 pounds and 55 grams of protein a day for a man whose ideal weight is 154 pounds. For comparison, typical intake for US adults is 65 grams to 90 grams. One ounce of meat or fish contains about seven grams of protein.