Chapter Three

THE HEART OF THE MATTER

The heart is an ordinary muscle with an extraordinary responsibility: keep pumping non-stop, two and a half billion times in an average lifetime. Blood needs to constantly transport oxygen and nutrients to cells and carry carbon dioxide and waste products away. The only thing keeping blood flowing is the heart. Anything that works so hard deserves a break once-in-awhile, right? But what we call a "heart-attack" is just an exhausted heart taking a break. Of course, no one wants to suffer a heart attack. Unfortunately, sometimes it takes actually having a heart attack to get some to change destructive dietary habits. Other times, despite the best efforts to keep the heart healthy, some individuals still suffer heart problems due to factors they cannot control. In this chapter, we explore the heart, the risk factors for developing heart problems, and how DHA might help lower the risk of developing heart disease for some people.

Q. How does genetics affect heart problems?

A. Heredity plays a great role in our lives. Our genes dictate the color of our eyes and hair, whether we are right or left handed, even to some extent our talents and interests, as well as how susceptible we are to health ailments like heart disease. According to some studies, people with two immediate family members suffering from heart attacks before age 55 are 5-10 times more likely to have heart attacks than those in families with no history. Heredity also influences several of the other risk factors, such as susceptibility to high blood pressure or high cholesterol levels.

Through a new and exciting field called genetic therapy, modern medicine may soon change heredity from an uncontrollable to a controllable factor. Researchers are exploring whether they can actually alter the genetic code in cells to treat heart disease, cancer, and other diseases. By introducing new genetic material into defective cells, they hope to change those cells into healthy ones, capable of producing the essential proteins and other factors, which normally protect against heart disease. For those genetically predisposed to heart disease, this represents the ultimate intervention, which may save their lives.

Q. Is it true men are more prone to heart ailments than women?

A. Heart disease does not distinguish between the sexes. Women suffer, too, although the female hormone estrogen helps to delay the onset of disease by about ten years. Consider these statistics from the American Heart Association:

One in nine women between the ages of 45-64 has some form of heart disease or stroke; this ratio soars to one in three at age 65 and beyond.

One in six men aged 45-64 has some form of heart or blood vessel disease; in men 65 and older the ratio decreases to one in eight.

Apparently, the risk for men is higher earlier, while the risk for women increases after menopause.

Q. Why is smoking bad for the heart?

A. Of the factors we can control, smoking is the most damaging to the heart. Nicotine constricts blood vessels, increases blood pressure and heart rate, and thus places great stress on the heart. Carbon monoxide poisons all the cells in the body by starving them of oxygen. Smoking also makes blood cells sticky, increasing the risk of forming clots inside blood vessels. Overall, smokers are 70% more likely to die of heart disease than non-smokers. Quitting smoking is the only remedy, and fortunately, the damages caused by smoking are reversible. Ten years after quitting smoking, the risk of developing heart disease is nearly the same as for non-smokers. Recent studies show significant improvements even after 1 year of smoking cessation. Actually quitting, though, may be impossible for some people without professional help, which is readily available through the local American Lung Association and other health organizations.

Q. Can stress really cause heart problems?

If your doctor orders a vacation, take her seriously! Stress releases adrenaline, a hormone which constricts blood vessels, raises heart pressure and rate, and readies your body to fight or flee a threatening situation. In an emergency, that is exactly what you need, because adrenaline provides the extra energy and alertness you need to jump out of the way of a swerving car or other danger. You may even find this feeling exhilarating, as your enhanced senses makes you feel more alive. In fact, some people live for this "adrenaline high" and seek out thrilling activities even for fun.

Chronic stress definitely harms the body. Quite simply, it exhausts it. The high blood pressure may damage the inner walls of blood vessels, increasing the risk of collecting sticky cells there and forming clots, which may then diminish the flow of blood. Moreover the nervous system becomes negatively conditioned, promoting processes which affect the heart.

Much advice has been given to help reduce stress, including practicing relaxation exercises, making time for hobbies and other interests, regular exercising (though, not in competitive sports), and learning not to take offense too easily. If stress comes as a natural part of your occupation, making efforts to deal effectively with stress is especially important.

Q. How can DHA reduce my risk for developing heart problems?

A. A standard part of all medical check-ups is the blood test. The health of your cardiovascular system is reflected in many ways in the blood. Doctors pay close attention to such things as

- HDL (high-density lipoprotein) cholesterol levels, the higher the better
- LDL (low-density lipoprotein) cholesterol levels, the lower the better
- triglyceride (fat) levels, the lower the better
- platelet stickiness, the lower the better.

Here is where DHA and fish oils can help. For a long time, medical researchers have known that eating fish and fish oils reduces the risk of heart disease. They pinpointed the agents of these benefits to the two omega-3 fatty acids, EPA and DHA. At first, both were thought to be act similarly in helping the heart, but recent studies suggest each play unique roles. (Some of the studies that follow are double-blind studies. This simply means that neither the participants nor the doctors or nurses involved knew who was getting the active substances, in these cases, DHA or EPA, or the placebos. This design minimizes psychological effects, placebo effects, which may cause some participants to manifest beneficial results, even when they got only placebos.)

Q. How does DHA supplementation affect HDL and triglyceride levels?

A. In a double-blind study led by Dr. S. Grimsgaard at the University of Tromso in Norway, 234 health, non-smoking men were divided into three groups. The first group took 3.8 g EPA per day, the second group, 3.6 g DHA per day, and finally, the control group, 4.0 g corn oil per day. On average, triglyceride levels dropped 26% in the DHA group and 21% in the EPA group, compared to the control group. Although the difference isnÌt great, the decreases occurred consistently for every one in the DHA group, strengthening the argument that DHA had a definite role in reducing the triglyceride levels. Moreover, HDL increased in the DHA group.

Dr. Grimsgaard also noticed something very interesting. In the DHA group, not only did the blood levels of DHA rise by 69%, the EPA levels went up by 29% as well! Remember, these people were not taking EPA. And yet, the EPA levels in their blood significantly increased, too. In the EPA group, the blood levels of EPA rose 297%, understandably, but the DHA levels actually decreased by 15%! What all this suggests is that DHA was actually converted into EPA in the body, but the reverse did not happen. This is called retroconversion of DHA into EPA, because DHA is actually longer by 2 carbon atoms than EPA. As we discussed in chapter one, the body normally converts EPA to DHA, so this finding is very significant and may lead to a better understanding of the biochemistry of this process.

Q. How does DHA help control fat levels from rising after a meal?

A. Generally, after eating a meal, the triglyceride (fat) levels in the blood increase, a phenomenon medically known as postprandial triglyceridemia.. The more fatty the meal, the greater the increase in triglycerides. In a study by Dr. J. Hansen at the Tromso University Hospital in Norway, 14 healthy volunteers were given 4 g/day of either EPA or DHA. The EPA group enjoyed a small 19% decrease in the buildup of triglycerides after meals, while the DHA group had a much greater 49% decrease. That is, taking DHA helps cut the buildup of triglycerides in the blood after a meal by nearly a half! (Again, retroconversion of DHA to EPA was found, but no conversion of EPA to DHA. Rather, EPA was elongated only to another fatty acid, DPA, which is the same length as DHA with 22 carbons, but one less double-bond.)

Q. Which increases HDL more, taking fresh fish or DHA supplements?

A. Fish and fish oils are whole foods, providing not only DHA, but many other fatty acids and naturally occurring substances. A good question is whether the whole food is helpful, or a single nutrient from the food, such as DHA. To find out, researchers led by Dr. J.Agren at the University of Kuopio, Finland, performed a very interesting experiment with 55 healthy male volunteers. One group ate four fish meals a week (providing 700 mg DHA/day), another group took 4 g/day of fish oil (providing 950 mg DHA/day), and the third group, 4 g/day of DHA rich oil (providing 1680 mg DHA/day). In all groups, HDL increased and triglycerides decreased substantially, with no great differences. So, take your choice ÷ fish, fish oils, and DHA all promote healthy hearts!

Q. How does DHA directly help the heart itself?

A. So far, weÌve seen DHA and EPAÌs effect on various factors in the blood, such as HDL, triglycerides, and platelets. This double-blind study by Dr. S. Grimsgaard at the University of Tromso, Norway, examines how DHA and EPA affect the heart itself. Blood pressure, heart rate, and the physical mechanics of the heart were monitored in 224 healthy, non-smoking men, who took 4 g/day of purified DHA, EPA or corn oil. No change was found in blood pressure for all three groups. In the DHA group, heart rate decreased about 2 beats/minute, whereas in the EPA group, it increased about 2 beats/minute. The corn oil group experienced no change in heart rate. Finally, both DHA and EPA groups enjoyed improved heart pumping efficiency compared to the corn oil group. The results of this study are enlightening. DHA and EPA seem to affect the heart itself, making it a more efficient pumping muscle.

Q. How can vegetarians improve their heart health with DHA?

A. Vegetarians generally enjoy better health and lower risk of heart disease than their meat-eating counterparts. However, as first mentioned in Chapter Two, vegetarians have markedly lower DHA levels. As we saw, this may be detrimental during pregnancy and breast-feeding. One way to remedy the shortage is by taking DHA supplements. As first described in Chapter Two, Dr. J. Conquer at the University of Guelph, Canada, gave twenty-four healthy vegetarians either DHA (1.62 g/day) or corn oil for 6 weeks. Those who took the DHA enjoyed a 246% increase in blood DHA levels and a 225% increase in DHA levels in a certain kind of blood cell, the platelets, which help form blood clots. Moreover, they also had a 117% increase in blood EPA levels, and a 176% increase in platelet EPA levels. Here, we see retroconversion from DHA to EPA again. The researchers even estimated that about 11 to 12% of the DHA was retroconverted to EPA. The HDL of those taking DHA did rise, and their triglyceride levels decreased, a combination that lessens the risk of getting heart disease.