PLAQUE ON THE WALL

"My soul is full of longing
For the secret of the sea
And the heart of the great ocean
Sends a thrilling pulse through me"
LONGFELLOW, The Secret of the Sea.

Plaque on the wall of your arteries presents no happy picture at all. Essential body nutrition is supplied by the blood following through the arteries. The blocking of arteries that nourish heart results in angina pain, of brain arteries, causes stroke and if plaque grow in the arteries of limb, blood circulation is severely restricted to various parts of the body.

The incidence of plaque formation is steadily rising in the younger Western population, due principally to the modern lifestyle and diet. The disease itself, however, is not modern. The Egyptian mummies, several thousand years olds, show extensive blocking of the arteries. Today, just about all of us have some plaques on our walls; only half of us will survive it.

WHY DO ARTERIES GET BLOCKED?

The many miles of arteries in our body are frequently damaged and blocked for reasons which vary from our diet to our personality (table 5.1).

Table 5.1
REASON FOR BLOCKING ARTERIES,

Physical damage to arteries
High fat concentration in the blood
High clotting activity in the blood
Old age-fragility of arteries
Diseases: hypertension, diabetics etc.
Hormones produced in stress
Cigarette smoking
Genetic effects
Immune system deficiencies.
Free radicals, such as from rancid fat
Deficiency of vitamins such as B-6
Reduced antioxidant levels (A, C, E, Bs)
high insulin levels due to sources in food
Reduced levels of selenium and zinc

Physical damage to the arteries is the most common starting point for plaque formation. The arteries are continuously damaged as some 1.5 gallons of blood flows through them every minute at high pressure. Just imagine, by the time you reach age 40 your heart has pumped about 30 million gallons of blood through your fragile arteries. Given this kind of stress and considering the chemically reactive nature of blood, even copper or steel plumbing would give out, so why not the fragile arteries.

Once damage is reported in any artery, the body goes into motion to repair it immediately. The repair process consists of calling upon the help of several blood components, especially the platelets and the red and white blood cells to form a quick plug at the cite of damage, the whole process taking only a few minutes to completes. You have experienced an analogous process when you bruised or received cut on the skin.

The clotting process in our best defense against bleeding. However, unless checked quickly after repairs, the clots will continue to grow and block arteries. To assure that the clotting and constriction of arteries stops when repairs are completed, the body has an elaborate control mechanism, whereby the arteries produce chemicals to counteract the clotting action. However, if the clotting process is strong or its control defective, the large plaque is formed in the arteries precipitating angina pains, heart attacks and stokes.

Excessive clotting activity is a result of the neurotic state of the body's defense systems engendered by our modern lifestyle. If arteries are continuously damaged due to stress, cigarettes smoke, carbon monoxide, diet or a host of other causes, the body stays in an alert stage of defense and any assault, albeit small, is handled head on and in a flagrant manner. It is quite obvious that our lifestyle keeps the body in a state of alert and tension most of the time.

Another causative factor for atherosclerosis is the free radicals floating in the body. Diets high in free radicals such as charbroiled foods and rotten cocking oil should therefore, be avoided. The free radicals are highly charges molecules produced, for example, when oils or fats become rancid or undergo oxidation. Several nutrients such as vegetables, minerals such as selenium and zinc and vitamins such as A, C, E, B-1 and B-6, prevents the formation and dissipation of free radicals in the body.

MECHANISM OF PLAQUE FORMATION

Formation of plaques in the arteries is a complex process that takes years to complete. The process begins with a rupture of the artery either due to physical damage or to accumulation of fat, mainly the low density type, in the lining of the arteries. This fat forms deposits, or atheromas, which is Greek for porridge. The artery, whose repair result in the formation of plaques (figures 5.1 and 5.2)

The repair of the arteries involves summoning blood platelets to the site (there are about 1-2 billion of these particles floating in our blood) to release a chemical messenger, thromboxane, which includes two actions to prevents blood loss: one is the clumping of platelets and other blood cells and second, the narrowing of the opening of the arteries. To keep this process under control, the arterial walls release another messenger, prostacycline, to counteract the effect of thromboxane (details in appendix A-6). Both thromboxane and prostacycline have very short life spans and last only a few minutes after they released at the site of damage. The body must, therefore, be always ready t synthesize these prostaglandins on demand. The raw material for these chemical messengers is the unsaturated fatty acids, more specifically, arachidonic acid, supplied in our food.

There are two types of PGs formed, the type 2 from omega-6 fatty acids and the type-3 from omega-3 fatty acids. Whichever type of acid is present in higher quantity will provide its own type of PGs since the conversion of fatty acids to PGs is a competitive process where both types of fatty acids compete for the limited amount of enzyme available in the acids is high in blood, as a result of high consumption of vegetable fats, the type-2 PGs formed in excess will accelerate the process of plaque formation.

Saturated fatty acids, on the other hand, cause heart disease by promoting the initial infiltration of arterial walls which causes arterial damage. Therefore, both saturated and unsaturated fats in our blood are involved in causing atherosclerosis. It is difficult to assess which type of fatty acid is more harmful. In recent years, we have reduced the use saturated fats, but increased the use of vegetable oils, a situation which no better than if we had continued the use of saturated fats. This is contrary to the popular belief that only saturated fat is need to be avoided our diets but it certainly explains why the incidence of atherosclerosis has not declined in proportion to the reduced saturated fat intake. The key to reducing incidence of atherosclerosis is t reduce all type of fats, not just the saturated fat.

Most vegetable oils, rich in unsaturated fat, increase the concentration of arachidonic acid (AA), an omega-6 fatty acid, in the body which results in increased production of eicosanoids which elevated blood pressure, reduce the body's ability to fight off infections, especially cancer, and increase the tendency of saturated fat to collect in the arteries causing heart attacks and strokes. These findings shatter the myth that only people who consume large quantities of saturated fats have high risk of heart disease.

Similarly, stress and smoking also cause plaque formation by increasing the production of hormones such as epinephrine and norepinephrine, which are related to the clotting activity of the blood. It has been estimated that if all Americans stopped smoking, we would save at least 170 thousand lives per year, most highly productive men and women at the peak of their careers. It is encouraging that since 1965, the number of male smokers has declined by only 30 percent, but unfortunate that women smokers have decline by only 14 percent. On an average, there is about a 35 percent decline in the per capita consumption of all types of tobacco in this country. Yet, it is not enough. It is ironic that our government spends millions of dollars to prevent deaths from traffic accidents, but very little to save four times as many lives by discouraging the use of tobacco products.

The sex of an individual also determines his of her susceptibility to heart disease. Generally, younger women are relatively free from heart disease because of the protective effects of female hormones. However, when they reach the age of menopause their immunity is lost as a result of reduced female hormones. The male hormones, on the other hand, increase the blocking of arteries by keeping the clotting process hyperactive. This is a result of evolutionary adoption when man, facing uncertain elements, was victim of the "fight or flight" syndrome. Even today, stress from everyday chores is sufficient to keep the body's defense system alert and hyperactive. As women have increasingly taken on the role of breadwinners, their risk of heart disease has risen significantly. As we age, the risk dying of heart disease increases because our arteries harden, become more brittle and lose their resilience, all of which contribute to increased blocking of arteries.

The fact that each individual responds differently to the multitude of factors which govern blocking of arteries, proves that genes too play a role. Our genes determine how resistant we are to heart ailment; genes control the vulnerability of arteries to physical damage, infiltration of blood fats, and the decline balance of the chemical messengers involved in plaque formation; genes also control our stressability, fat metabolism and hypertension. However, at times, genes have been a catchall excuse for effects which defy scientific explanation.

The biggest genetic myth was recently shattered when the statistics on atherosclerosis was summarized for the world population. Earlier observations from postmortem reports on soldiers killed in recent wars had shown massive atherosclerosis in the Americans as compared to Chinese and Japanese soldiers. This was attributed to genetic immunity in certain population and coincided with the belief that the Japanese and Chinese have genetic immunity to heart diseases. New studies show that the Japanese who settled I Hawaii lost immunity to heart disease once they adopted the Western lifestyle and diet, disproving the early myth.

Another interesting observation compares Eskimos and Finns. Although both belong to the same Mongolian race, the Finns show a much higher rate of heart disease than do the Eskimos.

HOW TO AVOID BLOCKED ARTERIES?

Having understood the factors that cause our heart to go on blink, we should be to devise concrete means to counteract them. Most of these measures can be classified as either dietary or nondietary. The nondietary measures comprise mainly the use of drug, physical exercise, reducing smoking and avoiding stress to keep our hearts healthy. However, the need for these measures can be significantly reduced and other factors, such as genetic tendencies and aging counteracted, if the dietary measures are properly instituted.

The dietary measures consist mainly of selecting food which least promotes plaque formation: the choice of saturated vs. unsaturated fats in our diet.

CHOICES OF SATURED VS. UNSATURATED FATS

Reducing the use of saturated fats, advice that has been constantly repeated, is of prime importance. Plaque formation is either caused by high fat concentration in the blood or the transformation of fat into plaque when an artery is ruptured. The type of fat which is most dangerous in this regard is the low and ultra low density lipids which are mainly made up of triglycerides, some cholesterol and plasma proteins. The concentration of these lipoproteins is decreased if we reduce the use of saturated fats.

The major contribution to our saturated fat (appendix A-1) comes from the cooking fat, and the meat and dairy products in our diet. It is relatively easy to cut down saturated fat coming from cooking oils. Whatever fat is present in our food first passes through our blood and if it is solid on our plate, chances are it will quickly turn solid in our blood also. The rule of thumb is that if a cooking fat solidifies at room temperature or clouds in the refrigerator, it is not good for health. Just remember if it does not solidify at room temperature, it has less than 20 percent saturated fat.

Reducing consumption of saturated fat is, however, not an easy task because of the concentration/quantity relationship of fatty foods. The quantity of saturated fat consumed depends not only on the concentration of saturated fat in the food but also on the quantity of food consumed; for example, a common serving of french fried potatoes has less saturated fat than a routine single serving of yogurt or milk. What is worse, therefore, french fries or yogurt?

Of course, there are additional considerations such as vitamins and minerals supplied by milk which are not provided by french fries. However, in a planned dietary program these supplements can be provided easily by other foods. The goal should be to reduce consumption of all saturated foods (table 5.2). It is interesting to note that, with few exceptions, most saturated fat foods provide about same quantity of saturated fat whether they are low or high in it because of the amount we eat.

TABLE 5.2
SATURATED FAT IN COMMON FOOD

Given the bad effects of saturated on our health, unsaturated fats, derived from vegetable sources, have become fats of choice during the past 20 – 30 years. These fats solidify at much lower temperature and are generally preferred because of their perceived lesser harmful effects. This theory has been refuted. Omega-6 fatty acids in vegetable fats increase the tendency to forms plaques exacerbating the effects of the saturated fats (appendix A-6). There are also other deleterious effects of omega-6 acids which will be discussed later in this book. The current consensus is that vegetable oils are equally as harmful as saturated fats are taken in excess.

It has become increasingly clear that we should avoid all types of fats, vegetable and saturated animal, but the type of food Americans prefer makes this next to impossible. There are too many sources of fat, based on cocking methods, that most us may not even be aware of (table 5.3)

Table 5.3
HIDDEN SOURCES OF FAT

Just when attempt to reduce fat in our diet may seem like a lost cause, comes the good news that not all types of fats are bad. The fat in fish can be highly beneficial to the body. The omega-3 fatty acids, available only in fish, counteract the effect of both the saturated and unsaturated fats in our diet and restore the body system damaged by these undesirable components of our diet.

THE UNIQUE FISH FAT

The effect of a fish diet on blood chemistry is related to its consumption in large quantities. For example, a recent study reported from Japan compared the blood level of omega-3 fatty acids in people living in Kawazu, a fishing village, with that of the population in the neighboring Kamagaya, a predominantly farming village. The report showed that when the fish is preferred diet (250 G/day), the ratio of omega-3 over omega-6 fatty acids in the blood remained high, whishes the key to reducing risk of heart diseases. In this study, the fishing population had only one-third the clotting activity compared to the farming-village population. The incidence of heart disease was proportionally smaller in the fishing population as well.

Additional studies in Denmark have been shown that whereas more than half of the deaths there are attributed to heart disease, less than eight percent of Eskimos deaths are a result of heart problems. A comparison of the diet of the Danes and the Eskimos (appendix A-7) quickly solves this discrepancy.

The Eskimos take twice as much cholesterol per day as the Danes, but their consumption of omega-3 fats is about 5 times higher than the Danes. Of great importance in our diet is the "P/S" ratio, the polyunsaturated to saturated fat ratio, which is about four times higher in the Eskimo diet compared to the Western diets.

Omega-3 acids exert two distinct actions in the body, physical action due to their low freezing points and oily nature, and a chemical action altering the type of chemical messengers produced in the body.

THE PHYSICAL ACTION

Fish sailing in the cold arctic water remain supple and flexible because of high concentrations of omega-3 fatty acids, which keep the membranes of the cells from freezing; in other words, the low freezing property of these fatty acids maintains the "fluidity" of the body membranes at low temperatures. Thus, the cellular membranes of anyone consuming large quantities of fish will have higher "fluidity", reducing the rigidity of arteries and lowering the blood pressure, both of which contribute to reduce blocking of arteries.

The higher concentration of omega-3 fatty acids in the body also makes the red blood cells more flexible and comfortable, allowing them to more readily and reach oxygen starved tissues which improves the utilization of energy in the body.

THE CHEMICAL ACTION

Omega-3 fatty acids produce PGs such as thromboxane and prostacycline, similar in chemical structure to the ones produced by the omega-6 fatty acids but with different effects in the body. The thromboxane causes clotting and narrowing the arteries whereas prostacycline counteracts these effects. The thromboxane formed from omega-3 acid does not have the clotting ability therefore the net effect is that fish fatty acids prolong bleeding, reduce plaque formation, all by soothing the hyperactive clotting mechanism of the body (appendix A-6).

The effectiveness of a diet rich in omega-3 acids is measured by how it alters the ratio of the omega-3 to omega-6 fatty acids in the blood. A high ration means either a higher concentration of omega-3 r a lower concentration of omega-6 acids. Keeping this ratio high result in a substantial reduction in plaque formation. This ratio in the Eskimos is four times higher than in the Japanese population and 70 time higher than U.S. and European populations. The overall incidence of heart disease among these populations can be correlated to his ration directly. It is easy to understand why this ratio, and not the concentration of either types of fatty acids in blood, is important. The omege-3 and omega-6 fatty acids compete for conversion to the chemical messengers responsible for plaque formation; hence, whichever type of fatty acid is present in higher quantity with respect to the other prevails. The goal is to have a high concentration omega-3 and low concentration of omega-6 acids in the blood.

It is important to know that all of the effects of omega-3 fatty acids are transient nature and if one stops eating fish or taking supplements of fish oil, the platelet counts and their ability to stick to the wall return to normal.

A similar mechanism applies when aspirin acts to reduce plaque formation, except that this effect is much more prolonged. Aspirin destroy the enzymes which cause conversion of fatty acids to prostaglandin, whereas in the case of omega-3 fatty acids, they are only temporarily blocked. A fish diet combined with aspirin, will prove tremendously effective in prolonging bleeding times while reducing the stickiness of platelets to cell walls.

The phenomenal effects of a fish diet or omega-3 acids, on reducing the incidence of heart disease should be appreciated by all those who are at high risk for these diseases.