Food for Life: How the New Four Food Groups Can Save Your Life (10 page)

By now, you can see why we are hearing the
V
word so much these days. Vegetarian foods are the most powerful foods for a healthy heart. You may be wondering how one goes about making such a change in diet, and what will be left to eat. I made this change myself several years ago and I know many other doctors and patients who have done so as well.
Chapters 6
through 8 will guide you through the transition step by step, and I think you will be impressed by the power of this change and may well wish you had made it earlier.

When you do make the switch, give it a chance to work. Do not include small amounts of chicken or fish in your diet and expect to get the same effect. For many people, eliminating those last few bits of animal products can make a big difference.

What we have discussed so far is only half the story. It is important not just to lower the amount of cholesterol in the blood, but also to keep it contained so that it does not cause any harm.

To extend our earlier oil truck analogy for a moment, imagine what would happen if a stone were to fly up from the roadway and poke a hole in a tank truck. The truck is flagged over to the side of the road. Ambulances, police cars, and teams of investigators arrive on the scene, evaluating the risk of explosion and other hazards. Several lanes are blocked off, and traffic on the road is cut down to a trickle.

Something similar happens to your cholesterol transport packages. LDL packages can be attacked by free radicals, the dangerous molecules we learned about in
Chapter 1
. This free-radical damage is thought to be what actually sparks the formation of a plaque. When the LDL package is damaged,
the cells lining the artery pull it out of circulation. In turn, these cells are damaged by the LDL they have taken in.
⁸
Muscle cells in the area start to multiply and overgrow. These muscle cells are normally in the wall of the artery, giving it strength like the steel bands in a tire. But as they multiply they form a raised bump—a plaque—within the artery wall. And as the plaque grows in size, less and less blood can get past it.

Our bodies have a way of fending off free-radical damage to the LDL particles. Vitamin C is a powerful antioxidant in the bloodstream that is quick to neutralize free radicals. In addition, vitamin E molecules are packed onto the outside of the LDL, averaging six vitamin E molecules per LDL particle. Some free radicals will get past vitamin C, but vitamin E aims to limit the damage they do. As vitamin E stops free-radical damage, it is chemically altered. And vitamin C restores vitamin E again.
^9–
11

Beta-carotene also defends the LDL, working in areas of the body with different oxygen concentrations from those in which vitamin C is effective. For many years, the Physicians’ Health Study has been examining the effects of beta-carotene on 22,000 doctors. The study is run by Charles Hennekens of Harvard University. After six years, those consuming beta-carotene supplements had only about half the number of heart attacks, compared to those on a placebo. The subjects were using a supplement rather than vegetables. Their dose was 50 mg per day, the amount in four carrots or two sweet potatoes.
¹²
No one knows the exact amount for optimal protection, but it is clear that a vegetable-rich menu provides antioxidants that help the heart.

The antioxidants are not foolproof, however. To further protect LDL, we need to cut down on free-radical production. That means avoiding the omega-3 fatty acids in fish, which are unstable molecules that oxidize easily, causing the production of free radicals. Omega-3s are needed by the body for healthy skin, eyes, and nerves, and as raw materials for building other biological molecules; but vegetables such as broccoli, spinach, lettuce, and beans provide omega-3s in a form that is more stable and also more modest in quantity.
^13–
15

The value of fruits, vegetables, and grains, then, is not just that they contain no cholesterol at all and very little fat. They also supply antioxidant
vitamins that offer some protection and hold a more stable form of omega-3 oils.

As we saw in
Chapter 1
, iron is part of the problem, too. It acts as a catalyst for free-radical damage. When iron is plentiful in the body, free radicals have a field day. In a study of nearly 2,000 men published in 1992, researchers in Finland demonstrated that iron stored in the body is a major contributor to heart attacks. The more iron you have in your body, the higher is your risk of heart disease.
¹⁶

Luckily, the same kind of diet that lowers cholesterol levels also lowers iron. Cutting out meat doesn’t just cut out cholesterol and fat. It also cuts out some of the iron that can damage the heart. “Meat is a one-two punch,” said Harvard University biochemist Randall Lauffer. “It contains a certain form of iron that is very rapidly and easily absorbed. And it contains saturated fat and cholesterol. So every bite of meat is contributing to two problems in the body—both of which lead to heart disease and possibly other chronic diseases that are common in Western meat-eating cultures.”

Iron makes atherosclerosis more likely to start. It also makes atherosclerosis more deadly. The reason, apparently, is that as circulation is restored after a heart attack or after a surgical procedure such as angioplasty, the influx of blood causes more free radicals to form, a process which is greatly increased by iron.

It is not just people with extremely large amounts of stored iron who are at risk, as Dr. Lauffer points out. “We are also very concerned that even moderately elevated iron levels could increase the risk of atherosclerosis— the blocking of the coronary arteries that supply blood to the heart—as well as making a person’s heart more susceptible to damage when they do suffer a heart attack.”

Iron may help explain why men and women have very different risks of heart disease. Before menopause, women have a much lower risk, but after menopause their risk rises to match that of men. Scientists have assumed that the difference must be due to hormones, but have found no compelling explanation. But it may be that men’s higher risk of heart problems is because they start accumulating iron in their bodies at an earlier age. For women, menstruation naturally removes iron on a monthly basis. After menopause, iron accumulation rapidly occurs and heart disease rates climb.

“The iron levels match exactly the mortality rates of heart disease in men and women,” Dr. Lauffer said. “Men get very high iron levels early in life,
say twenty years old, whereas women’s iron levels are held down by the natural loss of iron through menstruation. As soon as that ceases, however, their iron levels bound up quickly to that of men and, at the same time, the incidence of heart disease increases.” As we noted in
Chapter 1
, vegetarians are not headed for iron deficiency. Rather, they have lower, safer amounts of stored iron in their bodies.

Some people have used the free-radical theory as an excuse to return to burgers and fried chicken. Who cares about cholesterol, they say, if you have lots of antioxidants in your body? Well, there are several things wrong with that thinking. First, these animal products contribute a load of fat and iron that
encourages
free-radical damage. Second, the more cholesterol you have in your blood, the more likely it is that some of the LDL will be hit by a free-radical assault.

We do not want high cholesterol levels any more than we want convoys of oil trucks continually traveling up and down every highway and street, even if they try to drive safely. Accidents happen, both on the road and in your body.

It is no surprise that grains, vegetables, fruits, and legumes are powerful foods for a healthy heart. They contain no cholesterol at all. They have very little saturated fat. The iron they contain is less likely to contribute to iron overload, owing to more modest absorption. And plants contain enormous amounts of natural antioxidants.

Certain foods seem to have a particular cholesterol-lowering effect, and it is not just oat bran anymore. Oat bran, of course, displaces high-fat, high-cholesterol foods. Every spoonful of oatmeal you have for breakfast displaces the eggs and bacon you might otherwise have ingested. And oat bran seems to have an additional effect owing to the
soluble fiber
it contains.
^17
,
18
(Soluble fiber simply means fiber that dissolves in water, as opposed to wheat bran, which does not dissolve.)

If you want a technical explanation of oat bran’s effectiveness, here it is. The liver converts cholesterol into bile and sends it down the bile ducts and into the intestine. There, fiber carries it away along with the digestive contents.
¹⁹
In order to replace these lost bile acids, the liver pulls cholesterol out of the blood and uses it to make new bile acids. The result is lower cholesterol levels. If there is not enough fiber in your diet, however, the bile
acids moving along the intestinal tract can be broken back down into cholesterol, which can be reabsorbed into the blood. Fiber also seems to block some of the absorption of fat from the digestive tract and may actually reduce cholesterol synthesis in the liver.
^20
,
21

The good news is that there are plenty of other sources of soluble fiber. Fruits, particularly apples and citrus fruits, are very rich in
pectins
, a soluble fiber found in their cell walls and between the cells. Cooks are familiar with pectin as something that is in some fruits and that gels as it cools to make jams and jellies. In scientific studies, pectins have been shown to help lower cholesterol levels.
^22
,
23

Even the humblest of foods, the bean, contains substantial amounts of soluble fiber. As little as four ounces of cooked beans daily has been shown to lower cholesterol and triglyceride levels more than 10 percent in just three weeks.
²¹
Chickpeas,
²⁴
canned beans,
²¹
and other whole beans
^25–
28
and bean extracts such as guar gum (a bean extract often used in commercial food products) are all effective.

Researchers at the University of Toronto used pinto beans, chickpeas, kidney beans, and lentils in a cholesterol-lowering study.
²⁹
The subjects lowered their cholesterol levels and triglycerides, and they also liked the addition to their diet. They kept the beans on the family menu after the study was over.

Barley, which is commonly used in soups, also contains soluble fiber and effectively reduces cholesterol levels. My suggestion is not to focus on the variety (e.g., oat bran, soybeans, or barley) that is getting press attention for the moment, but simply to build your menu from a variety of grains, vegetables, fruits, and beans—the real power foods for a healthy heart. Among them you will get lots of beneficial soluble fiber.

Although this is a book about healthful foods, I do want to touch briefly on some other contributors to heart disease. It is not much use having a healthful meal if it is followed by a cigarette. Researchers have studied other risk factors and found that these factors can affect your heart, just as a bad diet can.

There is no doubt whatsoever that tobacco use is a risk factor for heart disease. People who smoke have a much higher risk than others do. Moderation in tobacco use is not what should be recommended. It is essential to quit.

I used to smoke cigarettes on my way to the hospital during my internship. I knew how risky tobacco was, but it was very hard to stop. The answer, I believe, is simply to keep trying. It took me many tries, and eventually it stuck.

Regarding alcohol, there has been more conflict. There is a long-standing debate as to whether alcohol boosts HDL and whether it might actually help the heart. Some studies have shown that teetotalers do not live as long as moderate drinkers. On the other hand, some teetotalers are people who have been forced to stop drinking after years of alcoholism or in the face of illness, and it would be a mistake to conclude that what these people need is a good drink.

However this debate ends, martinis before dinner will not protect you against the steak that follows. And while there is no apparent harm with occasional use, regular alcohol use clearly contributes to other health problems, including an increase in risk of breast cancer.

Regular physical activity cuts death rates dramatically. The good news for nonathletes is that most of the benefits come from light physical activity such as daily walking. There is relatively little difference in the value of intense physical activity versus modest exercise, such as walking. But there is a big difference between getting any form of physical activity and never getting any at all.
^30
,
31
If you are spending long hours in your recliner, you may as well be test-driving your coffin.

Having said that, do not buy into the myth that exercise can undo the effects of a bad diet. This is simply not true. Take soldiers, for example. They get a lot of exercise, and tend to stay physically fit. But when doctors examined the hearts of 300 American soldiers killed in Korea, 77 percent had some atherosclerosis. In many, the plaques were of substantial size, and in some cases they had blocked off entire coronary arteries.
³²
These young men had grown up eating the typical American diet, and they had no hint of the powder keg waiting in their hearts. If you looked at the soldiers who
had plaques that were big enough to block at least half of the artery opening, they seemed fit. They were not overweight; their average weight was 153 pounds. They did not have high blood pressure. And their average age was under 23.
³³
But their “physical fitness” did not keep their arteries clear.