There are 4 sources of calories: carbohydrates, proteins, fats and alcohol. People can make good and bad choices for each of these types of calories. Carbohydrates, for example, are not inherently bad; rather there are good and bad carbohydrates. Similarly, proteins, fats and alcohol are not inherently bad, but there are good and bad choices within each of these categories. Whole grains like brown rice, legumes such as lentils and beans, and above-ground green vegetables are examples of good carbohydrates. They have a low glycemic index, meaning they do not turn into sugar quickly in the body. There are ‘‘bad’’ carbohydrates, however. Bad carbohydrates are ones which tend to turn into sugar quickly, causing excessive weight. Refined sugar, refined flour products, breads, root vegetables that grow underground, such as potatoes and beets, have a high glycemic index and are not optimal sources of energy.9 Consumption of these should be limited. Proteins are available in good and bad varieties. Fish and seafood, vegetable-based protein sources such as tofu and other soy products are good proteins. Less beneficial proteins are fatty red meats, which are high in saturated fat, and egg yoke, high in inflammatory arachidonic acid.
There are good and bad fats. Fish and fish oils are good as are avocado and olive oils; raw, unsalted nuts and seeds contain beneficial fats. Bad fats include deepfried foods, processed vegetable oils like corn oil, and ‘‘trans’’ fats such as are found in margarine.10,11 People are often surprised to learn that alcohol is also available in good and bad varieties. Red wine has benefit, as it is rich in phytonutrients such as resveratrol, an anticancer agent.12–14 Beer is an example of a somewhat bad alcohol, since beer is rich in amylose, which has a high glycemic index. Although this is the conventional wisdom, this is controversial.15
Caloric restriction
Caloric restriction has been proven to extend lifespan of laboratory animals.16,17 Lifespan is how long the longest living individual in a species can live. Currently, the maximum human lifespan seems to be about 120 years. No human being has ever been scientifically documented as living more than 124 years. But, like Olympic records, we expect this soon to be broken and rebroken again and again as Bridge Two and Three therapies come into their own.
For now, however, caloric restriction is the only thing proven to help lifespan. For example, fruit flies have a lifespan measured in days or weeks; laboratory rodents have a lifespan of two or three years. In animal experiments involving caloric restriction, researchers were able to extend the healthy lifespan of laboratory animals and insects drastically. Increases in lifespan of 50– 100 percent or more were seen. We know that consuming excess calories reduce life expectancy; conversely, restricting calories can extend lifespan, at least in laboratory animals.18
In yeast experiments done by David Sinclair, caloric restriction was shown to activate the SIRT1gene that expresses SirT1 deacetylase that stabilizes DNA, extending lifespan. The authors postulate that caloric restriction ‘‘could extend life-span by inducing SIRT1 expression and promoting the long-term survival of irreplaceable cells’’.19 Polyphenols are a dietary substance that also activates this gene and may extend lifespan by 70 percent in yeast. A potent polyphenol known as resveratrol is found in red wine.
Rodent experiments have been done by Richard Weindrich at the University of Wisconsin, and he has done gene profiling to find out which genes are turned on and which genes are turned off during the aging process. It seems only a handful of genes are involved. By caloric restriction, he was able to show 30–50% increase in lifespan in rodents, fish, spiders and other animals. We know that in youth certain genes are active and certain genes are not, and in aging, these often change. We know that caloric restriction can move those genetic switches in older animals to more closely resemble the gene expression of a younger animal.20 For humans we have the results of real life experiments, not laboratory data. For example, on the Japanese island of Okinawa, a common phrase is ‘‘hara hachi bu,’’ which means ‘‘belly 80 percent full.’’ This concept means you should try to eat approximately 80 percent of what you would need to feel full. You try to leave the table a little hungry. The caloric intake of the average adult Okinawan is 1800 calories per day compared to Americans who eat 2500 calories or more each day. This seems clearly related to their lifestyle choices and not genetics, because as Okinawans move away from their homes on Okinawa and adopt different lifestyles, they live shorter lifespans like their neighbors. So there is nothing genetic about their long lifespans. They live longer because of their lifestyle choices, particularly caloric restriction.21,22
Other lifestyle choices
Japan is a land of other healthy lifestyle choices – at least as far as diet is concerned. Even though many Japanese smoke and live high stress lifestyles, the number of Japanese over 100 years of age has doubled in the past five years. This is a new phenomenon felt to be due to improved health-care coupled with their underlying healthy diet. In 1998 there were 10,000 Japanese over 100 years of age. In 2003, five years later, the number had doubled over 20,000. Women, by the way, constitute 85 percent of this centenarian population in Japan.
It is interesting to compare this to the United States, a land characterized by bad lifestyle choices, certainly as regards diet. A leading cause of death in the United States is, in fact, poor lifestyle choices. Half of the deaths in the U.S. are the result of easily modifiable lifestyle choices. The number one cause of death in the U.S. is tobacco, which causes 18.1 percent of deaths. The second is bad diet and lack of exercise, which causes 16.6 percent of deaths.23
Another healthy lifestyle choice that people can make is regular aerobic exercise. Proper aerobic exercise consists of getting your heart rate up to 60–80 percent of your maximum predicted heart rate (which is equal to 220 less your age) and keeping it there for a sustained period of time. Some type of aerobic exercise should be done continuously for 30 minutes at least every other day. In addition to aerobic exercise, weight training and stretching are valuable.
In addition we can take nutritional supplements. Modern farming methods unfortunately have led to significant decreases in the vitamin and mineral content of our food.24 Also, almost no one eats enough fruits and vegetables to get adequate nutrition without taking supplementation. Chemical reactions in the body occur because of enzymes and many enzymes in the body need vitamins and minerals as cofactors in order to function properly. By taking nutritional supplements, you can ensure that the raw minerals are always available to ensure that your youth-sustaining enzymes function optimally at all times. By taking supplements we can help neutralize the now outdated genetic time bombs programmed within our genes designed to take us out of competition for scarce calories as we age. We can help accomplish some of the same goals by caloric restriction, namely turning genes of youth on and genes of aging off at least for a while.25 In effect, by aggressive supplementation and other lifestyle choices we’re trying to ‘‘reprogram our biochemistry.’’
Answers to all your Biology Questions
