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3. HOMOCYSTEINE
Early in 1997 the American Journal of Clinical Nutrition published research confirming a strong association between coffee consumption and elevated blood levels of a biochemical known as homocysteine.48 Elevated homocysteine is a powerful contributor not only to heart disease, but also to stroke, miscarriage, birth defects, and possibly Alzheimer’s disease. And the data is incontrovertible.
A huge study group (over 16,000 people), almost equally divided between men and women, was evaluated, and the researchers were careful to factor out variables like smoking, vitamin intake, and history of cardiovascular disease.
The study’s conclusion is definitive and crystal clear: As coffee intake increases,
so does the level of dangerous homocysteine in the blood.
But when I went on-line to see what my cardiologist colleagues were planning to do about this remarkable data, I found only stony silence. The consensus of opinion was to “wait for more information.” In other words, no medical organization was even going to mention this report to their members, let alone recommend moderation of coffee intake
More Information Comes In
A few months after the coffee and homocysteine report appeared the Journal of the American Medical Association (JAMA) published another landmark study, this one looking at homocysteine and heart disease.49 Turns out the homocysteine factor is far more important than anyone thought. In fact, the JAMA study concluded that, in terms of risk for cardiovascular disease, elevated homocysteine is “equivalent to [high cholesterol] or smoking.” People with the highest homocysteine levels had more than three times the risk for cardiovascular disease than those with low homocysteine.
There are now over fifty studies that illustrate precisely how homocysteine increases your risk of cardiovascular disease. While this is not the place for a detailed lesson in physiology, I’m not sure you’ll be hearing anything about the matter soon from your doctor, and it’s too important to ignore. This information could very well save your life (or at least a painful and expensive trip to the hospital).
You know that proteins are composed of amino acids. One of those amino acids, methionine, is commonly found in meat and dairy products, and when the body processes or metabolizes methionine, homocysteine is created as a byproduct. Normally, the body breaks down the homocysteine into harmless metabolites, but there are a number of factors that either prevent this breakdown or overwhelm the body’s ability to clear homocysteine from the blood.
Caffeine raises homocysteine levels in two ways. We know that the elimination of homocysteine from the blood requires optimal amounts of folic acid, vitamin B-12, and vitamin B-6. Caffeine depletes these vital nutrients.
Secondly, caffeine appears to interfere with the normal breakdown of homocysteine. A diet high in meat and dairy products, on the other hand, tends to overload the system. Combine the two and you have real trouble. Add smoking to the mix and you’re a walking time bomb.
What Exactly Does Homocysteine Do to the Body?
Research suggests that homocysteine damages blood vessel walls. These injury sites, known as lesions, start to collect the substances your body sends to repair the damage. This material builds up over time, accumulating protein, calcium, and cholesterol from the bloodstream and forming plaque, which ultimately
and cholesterol from the bloodstream and forming plaque, which ultimately blocks the artery.
Other researchers have found that homocysteine increases the stickiness of platelets, cells in the blood that are essential for clotting. As platelets become more sticky, the likelihood of abnormal clot formation (and subsequent stroke or heart attack) increases dramatically.
Elevated homocysteine also affects the blood vessels’ ability to dilate.
Remember that every time your heart beats, your arteries must expand (dilate) to accommodate the increased pressure. As homocysteine levels increase, however, the blood vessels lose this elastic ability and are damaged as a result.50 Consider that as we age, most people’s overall blood pressure increases.
Consider also the damage done to rigid blood vessels under conditions of strenuous exercise. Normally, blood pressure rises and arteries expand to meet the body’s increased need for oxygen and fuel. But when homocysteine levels are high, blood pressure increases and the blood vessels don’t expand. The result: accelerated damage, cardiovascular disease, and increased risk for heart attack and stroke.
Who’s at Risk?
While all caffeine users are at increased risk for elevated homocysteine, the following groups have been identified as very high-risk populations.
1. People with other risk factors. If you have high blood pressure or high cholesterol, or if you smoke, even a small increase in homocysteine will greatly increase your risk of cardiovascular disease.51
2. Diabetics. People with diabetes are at increased risk because homocysteine appears to be far more damaging to their blood vessels.
What’s more, they have reduced ability to clear homocysteine from their bodies. This greatly increases risk for heart disease, as well as degeneration of the eyes and peripheral circulation.52, 53 In fact, there are a number of reasons why diabetics should not drink coffee (see list on pages 199–200).
3. People with rheumatoid arthritis. Recent research has shown that people with rheumatoid arthritis also have a defect in homocysteine metabolism that makes them particularly vulnerable to even slight elevations of this biochemical.54 That may account for the observation that people with
rheumatoid arthritis often improve on a vegan diet (no meat, eggs, or dairy), which is naturally low in methionine.
4. People with a family history of Alzheimer’s disease. Alzheimer’s disease is also characterized by abnormally high homocysteine levels.55
While a cause-and-effect relationship has not been confirmed, the rationale for homocysteine-induced brain degeneration is not far-fetched.
Homocysteine appears to accelerate free radical activity, a process known to damage nerve cells.
5. The elderly. Studies indicate that as many as 50 percent of individuals over age sixty-five have elevated levels of homocysteine.56 Coffee drinkers in this group are therefore likely to have far more serious consequences than they might have experienced in their younger years.
What’s Being Done?
As far as I can see (and I’ve looked extensively), nothing is being done. A review article on the health effects of coffee was published in the Medical Tribune on June 25, 1997.57 This magazine is read by more physicians than any other medical publication. The word homocysteine did not appear in the article.
Instead, the American Heart Association was quoted as saying, “[M]oderate coffee consumption does not appear to increase a person’s risk of heart attack.”
In their current publication dealing with caffeine, the AHA statement is even worse: “Whether or not high intakes of caffeine increase the risk of coronary heart disease is still under study” (my italics).
In reality, the caffeine-homocysteine-heart disease connection has been thoroughly and exhaustively examined. Conclusive research has even been published in the AHA’s own journals!58 It’s just that no one appears to be willing to draw the obvious and important conclusions from the mountain of data already in hand.
RESEARCH CAPSULE
You’ve heard about HDL (high-density lipoprotein), the “good” cholesterol that lowers your risk of heart disease? Your doctor may have encouraged you to exercise regularly in order to raise the level of this protective factor. Well, if your homocysteine levels are high, all the HDL in the world won’t protect you.
Research just published in the American Journal of Cardiology shows that homocysteine is so damaging that it virtually eliminates any protective benefits obtained from high HDL.
Source: H. R. Superko, “Elevated High-density Lipoprotein Cholesterol Not Protective in the Presence of Homocysteinemia,”
American Journal of Cardiology, March 1, 1997;79(5):705–06.
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bsp; Three Steps You Can Take
Research appearing in the pages of dozens of medical journals now supports a prudent and effective approach to reducing your blood levels of homocysteine.
You’re not likely to read about these steps in a magazine or hear about them on the evening news. You probably won’t hear them from your doctor, and that’s because these important measures do not involve the purchase of expensive, patented drugs. Instead, they involve three simple steps: 1. Decrease your intake of meat and dairy products, and increase fresh fruits and vegetables.
2. Decrease or eliminate your intake of coffee.
3. Take a daily vitamin supplement that provides 400 micrograms of folic acid, 20 micrograms of vitamin B-12, and at least 5 milligrams of vitamin B-6.
A+B = Huh?
A: “We conclude that an elevated homocysteine level is now established as a strong and independent factor associated with all categories of atherosclerotic disease in both men and women.”
Source: I. M. Graham, L. Daly, Helga Refsum et al., “Plasma Homocysteine as a Risk Factor for Vascular Disease: The European Concerted Action Project,” Journal of the American Medical Association, 1997;277:1775–81.
B: “In conclusion, we found a strong dose-response relation between coffee intake and plasma homocysteine concentration. …
Given the widespread use of coffee, even small adverse
consequences will have important health implications.”
Source: O. Nygard, H. Refsum et al., “Coffee Consumption and Plasma Total Homocysteine: The Hordaland Homocysteine Study,”
American Journal of Clinical Nutrition, 1997;65:136–43.
C: “[M]oderate coffee consumption does not appear to increase a person’s risk of heart attack.”
Source: American Heart Association
4. HOSTILITY AND ANGER
Numerous studies have shown that hostility and anger significantly increase risk for heart disease and stroke.59 We now know that these emotions are tied to stress hormones in a vicious cycle: Anxiety and stress cause increased production of epinephrine and cortisol, which then affect mood, mind, and behavior in such a way as to create more stress, hostility, and anger. A common trigger? Caffeine.60
Importantly, the damage caused by the additive effects of caffeine and stress is often silent. Small arteries may spasm, cutting off blood supply to vital areas of the heart for short periods of time. The risk for rapid heartbeat (tachycardia), flutter, and arrhythmias all increase during periods of intense stress, but the victim, caught in the emotional spiral, is often completely unaware of the damage being done.
As you can imagine, one outburst of anger is not likely to give you a heart attack. The research is conclusive, however, regarding people in whom hostility and anger are common experience. At different points in life, we may find ourselves in jobs or situations that stimulate anger and aggressiveness.
Ironically, those are also the times when we tend to drink the most coffee.
Breaking this destructive cycle, therefore, involves changing our habits and awareness.
“We have found that anger can cause a weakness in the pumping action of the heart.”
Source: G. Segall, M.D., of Stanford University, Medical Tribune, 1991;32(14):17.
5. THE MAGNESIUM CONNECTION
Adequate magnesium is essential for normal heart function and even a slight deficiency of this mineral can have adverse effects on the heart and blood vessels. Diet surveys and blood tests show that millions of people consuming a typical American diet are not obtaining sufficient magnesium from their food.61, 62 Most of them are also drinking coffee, which has been shown to deplete
magnesium from the body.63, 64 You don’t have to be a Ph.D. in public health to see that this is a major problem. Low magnesium increases the risk for arrhythmia, congestive heart failure, heart attack, coronary vasospasm, hypertension, and stroke.65–66, 67> One recent report in the American Heart Journal noted that “the intricate role of magnesium on a biochemical and cellular level in cardiac cells is crucial in maintaining stable cardiovascular function.”68
“It should be realized that preventing the patient from a magnesium deficit is the first, and the application of magnesium the second best strategy to keep the patient free from cardiac arrhythmias.”
Source: M. Zehender, “Magnesium as an Antiarrhythmic Therapy Principle in Supraventricular and Ventricular Cardiac Arrhythmias,”
[German], Zeitschrist for Kardiologie, 1996;85 supplement 6:135–45.
Here is yet another vicious cycle. Research shows that Type A individuals (high-stress personalities) lose significant amounts of magnesium when faced with a stressful situation compared to Type B individuals (easygoing personalities.)69 But we also know that Type A people tend to drink a great deal more coffee than Type B folks. And it doesn’t really matter which factor comes first (stress or caffeine intake). The result is that the people who need magnesium the most are the ones whose stores are most depleted.
When was the last time your doctor measured your magnesium level?
Chances are it never happened, even if you are at risk for heart disease. Once again, that’s because nutrition, diet, and exercise are usually overlooked in favor of the “quick-fix,” drug-oriented approach. Some blood panels measure serum magnesium, but that reflects only the amount of the mineral that was being transported in your blood at the time the test was taken. It does not indicate the amount of magnesium in your body. You can obtain that important information by measuring the magnesium in red blood cells. Known as RBC magnesium, this valuable test can be done by most laboratories, but you’ll have to ask for it and pay for it yourself. Insurance companies, for the most part, do not yet understand the remarkable preventive benefit of maintaining optimal levels of magnesium, even though the data has been available for twenty years.
A special note for individuals with any form of heart disease: A new study has conclusively shown that oral supplementation with
magnesium can significantly reduce the incidence of arrhythmia.70
This does not mean, however, that you can drink all the coffee you want and simply take a magnesium pill. Coffee will deplete magnesium rapidly, even from a supplement, and increase your risk for heart disease in multiple ways. A sensible strategy for staying alive and healthy: Decrease or eliminate caffeine.
Supplement with a high-potency multimineral providing at least 400
milligrams of magnesium and 100 milligrams of potassium per day.
6. ALTERED BLOOD CLOTTING
When a person is killed by a stroke or heart attack, there are always direct and indirect causes. We’ve been discussing the indirect causes, those factors that contribute to the blockage of an artery. But the direct cause (the blocked artery) is also fairly complex, insofar as arteries do not usually build up sufficient plaque to stop all blood flow. The killer factor is often a blood clot that travels to the narrowed artery and plugs it up.
Today, it is common for people with atherosclerosis to be given “blood thinners,” drugs that decrease the clotting ability of the blood. The fact is, however, that millions of Americans are walking around with what is known as silent ischemia. Plaque has built up in their arteries, but not to the point of causing pain or abnormal heart activity. Health experts are concerned because the number of people with silent ischemia is increasing dramatically, and not just because the baby boomers are reaching their fifties. The most frightening thing is that this condition is being diagnosed in people who are in their thirties and forties.
Silent ischemia is “an accident waiting to happen.” If a person should form an abnormal clot and if that clot finds its way into a narrowed artery leading to the heart or brain, he or she is finished. You need to remember that in a large percentage of cases, the first sign of cardiovascular disease is a fatal heart attack.
Anyone who has owned a house will tell you that plumbing requires regular maintenance, and even then, after thirty or forty years, large sections may have to b
e replaced. And that’s steel and copper pipe. Your plumbing (over 1,000
miles of blood vessels) is delicate tissue, subject to the same forces of pressure, erosion, wear, and tear. And the way the body fixes leaks involves clotting. You might not know that in addition to the cuts, punctures, nicks, and scrapes that are visible signs of clotting, you spring internal, invisible “leaks” on a regular basis, and your body fixes itself remarkably—like having a self-repairing plumbing
and your body fixes itself remarkably—like having a self-repairing plumbing system in your house.
But this mechanism must be finely tuned. If your blood clots too slowly, you can hemorrhage. If your blood clots too fast, you’ll tend to form unnecessary clots that can wreak havoc in the body. Interestingly, the clotting mechanism is very much affected by what we eat and drink. A diet high in meat and dairy products will tend to increase the “stickiness” of your platelets, thereby making your blood more likely to clot abnormally fast.
I started wondering about the effect of coffee on blood clotting when I was studying the stress response. We know that adrenaline accelerates blood clotting, and from an evolutionary point of view, this makes perfect sense. After all, throughout human history, the events that got our adrenaline up were threats to our survival, and those threats often resulted in injury. The stress response thus produces alterations in the blood to make it clot faster.
But today, as I have explained, stress is remarkably different. Instead of facing a saber-toothed tiger or a club-wielding foe, we’re facing deadlines, crammed schedules, traffic jams, and mortgage payments. None of these involve physical injury, but we cannot change our genes. Stress still produces alterations in blood clotting, and on top of this, millions of people accelerate the clotting mechanism of their blood every morning when they slam down their first cup of coffee.