Food for Life: How the New Four Food Groups Can Save Your Life (3 page)

I suggest that you think short term. Rather than resolve to make any long-standing changes in your eating habits, a three-week period is all you need to consider. Why three weeks? That is how long it takes to break an old habit or start a new one.

In my medical practice I have helped many people overcome all kinds of bad habits, ranging from tobacco and alcohol use to cocaine and heroin abuse, not to mention destructive food habits of every variety. Time and again I find that it takes an average of about three weeks for a new positive habit to take root, and a few weeks more for it to become really solid.

First, familiarize yourself with the concepts in Chapters 1 through 7. Then follow the menu program or take your pick of the recipes and food items in
Chapter 8
. For three weeks, stick to these foods. You can add others, too, if they meet the same nutritional criteria. Try the simple exercises and stress-reduction tips. At the end of three weeks, see how you feel. If you like the results, continue with the program for another three weeks.

Please note that every person has a different medical history, different genetic endowment, and different potential risks and benefits from dietary changes, so the results of dietary change will vary from one person to the next. The same is true of any medication or medical procedure.

Also, nothing in this book takes the place of medical decision making between yourself and your physician. If you have a particular medical condition, obesity, or are on medication, consult your doctor before making a substantial change in your diet. Dietary changes can sometimes change your need for medication or have other important effects. Also see your doctor before any substantial increase in physical activity if you are over forty or have any medical problem.

If you are pregnant or nursing, or if you follow this program for more than three years, please consult the guidelines in
Chapter 6
.

The science of nutrition is controversial and is changing gradually, so I encourage you to consult other sources of information, including the references listed in this volume.

If, for whatever reason after the three weeks, you decide to resume the average American diet, please see your doctor regularly, and reconsider changing to the powerful menu described in this book.

Some people seem to stay young forever. They never lose their hair, their skin stays youthful, and they remain slim and physically active. Others go bald before they reach twenty, develop an extra layer of fat by thirty, and have deep wrinkles by forty. The assaults of time are not entirely due to genetics. Foods can be part of the problem. And, more important, certain foods contain natural ingredients that can help protect against aging.

Since the 1950s a substantial body of evidence has shown how foods, properly selected, have a great deal of power to help us stay young. This evidence is now collectively known as the
free radical theory of aging
. While it was a heretical proposition in the 1950s, it is now widely accepted by scientists and nutritionists, who see free radicals as a contributor to skin aging, cataracts, arthritis, and, perhaps, to the most basic aspects of the aging process.

Certain foods slow the effects of time, while others speed them up. In addition, foods can change the amounts of hormones in the body. In turn, these hormones play a critical role in many bodily functions, from puberty to the onset of baldness.

In this chapter we look first at the signs of aging and how to guard against them: changes in our skin, our hairline, our eyesight, and our bones. Then we look at lifespan itself, and the factors that affect the speed with which we grow up and grow old.

Can you keep your hair by eating right? Can your skin keep its youthful appearance? Are you doomed to wrinkles, osteoporosis, and cataracts? The fact is, there are fascinating new scientific findings in each of these areas. And enough specific information is available that you can put it to use right now.

Your skin is made of millions and millions of tiny cells, as is your heart, your brain, and every other organ in your body. Each cell has many jobs to do. Skin cells, for example, are not just bricks in a wall. They are very busy repairing injuries, neutralizing the effects of too much sun or various toxins, and taking in nutrients and modifying them for use as needed.

But cells are fragile things. They have only so much capacity to survive. If a small sample of your cells was put into a laboratory dish and given all the nutrients that the cells needed, at first they would grow. Each cell would divide into two, and their progeny would also grow and divide again. But sooner or later they would stop. Typical cells can go through the cycle of growth and division only about fifty times before becoming exhausted.
¹
That is biologically predetermined, although the time between one division and the next can be hastened or slowed.

So what does this mean to you? It means that if your body is constantly exposed to the damage of sun, toxins, tobacco, or alcohol, not to mention the chemical wastes produced by normal body processes, you might rapidly use up your cells’ capacity to replace themselves. If, on the other hand, you have a way to protect yourself, your cells would need to replace themselves less often and would therefore be able to retain their youth much longer.

The changes that most of us attribute to the aging process actually have very little to do with the passage of time. Compare the skin on your face to the skin on the inside of your upper arm. The skin on your upper arm is not exposed to sun, and it keeps its youthfulness much longer. These protected skin cells also retain more of their ability to grow and multiply. Sun-damaged skin is nearer the end of its lifespan.
²
Although the surface skin cells are constantly being replaced, the underlying skin becomes wrinkled and leathery and loses its resilience.

Skin samples taken during facelifts show the same thing: There are dramatic differences between areas as close together as the skin in front of
your ear, which is sun-exposed, and the skin behind it, which is not: the sun-exposed areas age prematurely.
³

There is, in fact, very little evidence of normal skin aging before age fifty. What passes for aging is mostly sun damage, or
photoaging
, which starts early in life. Photoaging gradually causes rough skin texture, wrinkles, distorted blood vessels, and spots of too much or too little pigment. If you were to examine sun-damaged skin under the microscope, you would see that the tiny elastic fibers that keep the skin supple are damaged, the outer skin cells have overgrown, and the blood vessels are dilated and damaged, too.
⁴
If you put a skin sample from a sun-protected area under the microscope, however, its baby’s-bottom youthfulness is still there.

How can we protect ourselves from this destruction? We can avoid sunburn and even try to stay out of the sun, but there is no way to avoid it completely, nor would we want to. What is more important is a chemical reaction that occurs in the skin, and also in all other parts of the body. This chemical reaction is a chief suspect in the gradual destruction of the body we call the aging process.

Like all the cells of your body, your skin cells need oxygen. It is the very basis of animal life, including ours. But oxygen is biology’s double-edged sword. As sunlight slowly bakes your skin,
⁵
oxygen molecules often become extremely unstable. They pick up too many electrons, or carry electrons in unstable orbits. These destabilized oxygen molecules are called
free radicals
. They are also produced, but to a lesser degree, in the course of the normal workings of the cells.

Free radicals are unstable, destructive molecules. They come in a variety of chemical forms, but all have one thing in common: They can attack and damage bystander molecules, rendering them unstable and ready, in turn, to attack yet other molecules, starting a chain reaction of cellular destruction. They attack the very tissues that make up your body.

If you were a tiny observer cruising through the blood vessels in a microscopic submarine, you would see free radicals attacking the cells of the body. They attack cell membranes and the tiny intracellular machinery. They can even damage DNA, the cell’s central control machinery, causing normal cells to turn into cancer cells. These attacks occur in the skin, the heart, the brain, and other organs. If we did not have a means to neutralize these free radicals, we would self-destruct in short order.

The damaging effects of free radicals are not a recent discovery. Physician
and researcher Dr. Denham Harman is a professor at the University of Nebraska School of Medicine and is head of the American Aging Association. In the 1950s, he was studying free radicals, which at that time were mainly of interest to chemists dealing with vats of industrial products. Harman suggested that free-radical damage might play a part in the aging of the human body.

What was to become one of the most important theories in human biology began with a bit of daydreaming. “After I had completed medical school and an internship in June 1954,” Dr. Harman said, “I went to work as a research associate at the Dormer Laboratory of Medical Physics in Berkeley. My time was my own except for one morning a week in the Hematology Clinic; I could have spent most of my time playing tennis if I had wanted to. But I used my free time to pursue my long-time interest in aging.” Much was already known about the biology of aging, and about the chemistry of free radicals in our environment. But the two had never been put together.

“You know how sometimes you are struggling with a problem and cannot seem to find the answer to it, and then some time when you’re thinking about something else, or maybe even dozing off to sleep, all of a sudden the solution hits you.” One morning in November 1954, Dr. Harman was sitting in his office reading, and suddenly it struck him that free radicals were not just sitting in vats of chemicals in our factories and warehouses. They might actually be forming minute by minute in the blood coursing through our veins, attacking the insides of our arteries, aging our skin, sparking the cellular havoc of cancer. Could free radicals be the key to aging processes? Could they play a role in cancer or heart disease?

“I spoke with people on the Berkeley campus about this possibility,” Dr. Harman said. “Most thought it was too simple an idea.” But other researchers took an interest in the theory. There is now a huge body of research showing that free-radical damage occurs every minute of every day in the human body. “Evidence began to build up,” Harman said, “and now, about forty years later, many scientists accept this, both for disease processes and for aging
per se
.”

Plants are hit by direct sunlight hour after hour, day after day. They don’t shrivel up and die; they thrive on it. Instead of being bleached or burned
by the sun, they are able to use its energy to power the chlorophyll machinery of their leaves, turning water and minerals from the earth and carbon dioxide from the air into building materials.

The fact is, plants would rapidly be damaged by the sun if they did not have one vital chemical in their leaves:
beta-carotene
. As the sun beats down on plant leaves, free radicals form just as they do in your skin, but beta-carotene removes the free radicals before they can do their damage Beta-carotene is a vital chemical all chlorophyll-containing plants use to neutralize free radicals as they are formed. In the 1950s, another researcher in Berkeley, California, developed a mutant single-celled plant that lacked beta-carotene. When he exposed this plant to light and air, it was wiped out in short order.
⁶

The technical term for a protective chemical like beta-carotene is
antioxidant
, meaning that it neutralizes free radicals and blocks the tissue oxidation that they could cause. Antioxidants work by allowing themselves to be attacked and damaged by free radicals, sparing the cell itself.

As our ancestors plucked plants from the ground and fruits from trees, they took beta-carotene for themselves. It passed into their bloodstream and became part of their own defense against toxic molecules. Today, when you add a leaf of fresh spinach to a salad or bite into a carrot, this natural chemical enters the cells of your body. You cannot feel it, but it is busy knocking out free radicals that would age the skin or damage your heart or other organs.

Chemically, beta-carotene is made up of two molecules of vitamin A. In the body, some beta-carotene splits, yielding its two molecules of vitamin A, which also has some protective effect. But beta-carotene has antioxidant powers that vitamin A lacks. The skin cream Retin-A, which made headlines for its ability to reverse the signs of aging skin, is a relative of beta-carotene.

Beta-carotene helps protect the skin against the damaging rays of the sun, and makes it harder to sunburn and easier to tan. People who are extremely sensitive to the sun owing to genetic skin diseases can tolerate the sun much longer when they have beta-carotene-rich diets or supplements.
^7
,
8
But beta-carotene’s effect on the skin is not news to researchers. As long ago as 1926, a clinician named J. H. Bendes wrote in a Minnesota medical journal that,