My friend told me that he has an issue with thick blood. I'm curious if anyone else has an issue? What causes it? What are the best ways to correct this issue?
In the short term, some possible causes of increased blood viscosity may be dehydration, psychological stress, cold temperatures (see here and here), heat stroke, increased hematocrit levels, hyperglycemia, increased triglycerides and chylomicrons in the blood, and perhaps exposure to air pollution and tobacco smoke. There's also a link between high blood pressure and high blood viscosity, perhaps relating to fibrinogen.
Based on that I would bet staying hydrated, avoiding stress, keeping hematocrit in check, preventing hyperglycemia and high triglycerides, and avoiding exposure to air pollution, smoking, and extreme temperatures would all be valid ways of avoiding thick blood.
Omega-3 supplements has occasionally been shown to improve blood viscosity, which doesn't surprise me. If fibrinogen is playing has a causative role in this, I suspect most methods of reducing inflammation would also improve blood viscosity.
Edit: I've read a little bit into whether increased blood viscosity may increase risk of diseases, specifically heart disease and stroke.
Several studies have found an association between heart disease and blood viscosity leading some to suggest increased BV may be a causal factor in the development of the disease. The Edinburg Artery Study also noticed this correlation, but when controlling for a number of typical risk factors like smoking and BMI this association left the building. That's the problem; because many things that are bad for your heart like smoking, inflammation, and high blood iron also increase blood viscosity, increased BV is likely to be correlated with heart disease. This is called a spurious relationship. Essentially, when C causes A and B it may appear that B is the cause of A since they will be seen together. Blood viscosity may increase heart disease risk, but I haven't seen convincing evidence for it yet.
It's also been noticed that people who've had strokes also tend to have more viscous blood. Elevated hematocrit and fibrinogen (the latter increased by inflammation) are factors increasing stroke risk and they both increase blood viscosity. A study on people with high levels of paraprotein, a condition that results in higher blood viscosity, found that higher BV might decrease cerebral blood flow, thereby increasing stroke risk (this study controlled for hematocrit). However, an interesting experimental German study concluded that blood viscosity itself does not appear to notably decrease cerebral blood flow. This is clearly an issue under debate, as this article outlines and I don't know the answer myself.
Ultimately I think high blood viscosity itself might increase risk of heart attack and stroke, but based on the evidence I think it's more likely that the main causes of high blood viscosity also increase risk of heart attack and stroke and blood viscosity itself is just a marker for these risk factors.
Jonathan V. Wright, MD. discusses this very issue in his Jan 2012 Newsletter. The subscription is not free unfortunately or I would post the link. I will copy it below even though it may be a bit long, I found it very interesting.
Learn how treating the most overlooked factor in heart health can reduce your risk of heart attack by 88% By Jonathan V. Wright, M.D.
Although cardiovascular disease has declined nearly 28 percent over the last ten years,1 it’s still the leading cause of death—and a factor in more than one-third of all deaths. It is also the most expensive disease process to treat, exceeding reported costs for treating all cancer and benign tumors.
But what if I told you that you could reduce your risk of heart attack by 88 percent with one very simple action? I’m not kidding—that “88 percent” number comes directly from solid research.
And it’s something I recently learned about, thanks to Dr. Ralph Holsworth, D.O.
As you know, I have many “special areas” in natural medicine (including diet, vitamins, minerals, bio-identical hormones, cell therapy, a variety of intravenous therapies, and much more). But there’s one area that I knew nothing at all about (and of course was not taught in medical school): The physics of blood flow.
One simple action can save your own life—and someone else’s too!
Dr. Holsworth showed me literally thousands of pages of research papers he’d collected, and one really caught my attention. In this research study,2 2,862 men ages 42 to 60 were observed for an average of nine years. Of the 153 men who had donated blood within 24 months prior to their first examination, only one man (0.7 percent) had a heart attack during the nine years, as compared with 316 of 2,529 men (12.5 percent) who did not donate blood.
After all the usual research adjustment for risk factors, the men who donated blood had 88-percent less risk of acute myocardial infarction as compared with the men who didn’t donate blood. (For the technically inclined, the difference between 0.7% and 12.5% had a “p<0.0001.” For the non-technically inclined, that means it’s really, really significant!)
The researchers wrote: “These findings suggest that frequent blood loss through voluntary blood donations may be associated with a reduced risk of acute myocardial infarction in middle-aged men.”
That’s great for men, but what about women? Between menarche and menopause, as everyone knows, women have blood loss every month. And in menstruating women not taking birth control pills, heart attacks and strokes hardly ever happen. Once that monthly blood loss ceases, a woman’s risk of heart attack becomes just as high as men within a decade or so.
The authors of the research paper summarized above attributed the dramatic reduction in heart attack risk to a reduction in circulating iron. While reducing serum iron may play a very small part, all the rest of the research has convinced me that the very large majority of the reason for this reduction was—and is—a reduction in blood viscosity (resulting in an increase in blood flow throughout the body).
The overlooked cause of atherosclerosis
Atherosclerosis begins many years before cardiovascular disease symptoms are evident. Current research suggests that, at some point, an injury occurs in the blood vessels, leading to the build-up of plaque. When atherosclerotic lesions build to a certain level or at specific locations in blood vessels, vascular disease can occur. And if blood vessels are completely or mostly blocked, chest pain and heart attack can occur.
Despite all the talk and advertising about cholesterol, despite all the publicity about smoking, obesity, diabetes, and high blood pressure, and despite excellent documentation, it appears that there’s another almost entirely overlooked cause of atherosclerosis: the way that the blood itself flows within those arteries.
Think for just a moment: If your blood is thick and sticky, is it going to flow along as easily in your arteries and veins as blood that is thinner and less sticky? Does tomato paste flow as easily as tomato juice? Of course not.
Even with all the other possible risk factors for the development of cardiovascular disease, direct measurement of the blood’s ability to flow is arguably the most important, and far and away the most overlooked.
Numerous studies have been done to demonstrate the relationship of blood viscosity to the development of atherosclerosis. In a study,3 researchers assessed 26 men with extensive heart disease and 25 healthy “controls” without heart disease between the ages of 30 and 55. Those with extensive heart disease showed a much higher blood viscosity than those who had little to no disease processes occurring. The differences could not be attributed to patient history. The study suggested a strong association between coronary artery disease and increased blood viscosity.
In the Edinburgh Artery Study,4 1,106 men and women between 60 and 80 years old were assessed to determine the relationship between factors associated with early atherosclerosis and angina. They looked at variables including the ability of red blood cells to aggregate, and compared these results to controls. The study results suggested that blood viscosity played a part in the development of early atherosclerosis.
Blood Flow 101
Blood viscosity is a direct measure of the blood’s resistance to flow. It affects not only how hard the heart has to work to circulate the blood, but also the level of stress and strain, injury, and inflammation the blood causes to the arteries. The thicker the blood, the more abrasion and damage it does to the lining cells (endothelium) of the arteries. When endothelial insult occurs, lipids and other inflammatory cells migrate into the endothelial and subendothelial tissue spaces to repair the damage. Atherosclerotic lesions grow, plaque grows, and the risk of plaque rupture grows too.
Increased viscosity increases the friction—yes, friction—as blood rubs against the inside linings of blood vessels. As viscosity increases, friction increases, and arteries stiffen and narrow, resulting in increased friction and deceased blood flow within arteries and veins.
The cardiovascular system is “closed.” Except when significant injury occurs, blood does not leave the intricate system of blood vessels that permeate the body, whereas the oxygen and other micronutrients it carries diffuse through the capillary membranes into the tissues. Since the cardiovascular system is “closed,” the viscosity—thickness and stickiness—of what the heart is pumping is highly significant in cardiovascular health.
As your blood circulates from the heart through your arteries, if it’s too thick and sticky, it may actually cause injury to the inner lining of the arteries in areas where the arteries expand to accommodate blood flow. To try to repair and protect the friction-induced damage to the endothelium, thickening and hardening (often called “plaque”) occurs in those areas.
As the lining of the blood vessels incurs more and more damage, the flexibility or elasticity of the arteries decreases, and actual arteriosclerosis begins. Arteriosclerosis (the initial damage) proceeds to atherosclerosis, a biological adaptive process intended to protect the lining of the blood vessels from further damage, a protective mechanism known as the “protective adaptation response,” described 10 years ago by Drs. Kensey and Cho in their textbook, The Origin of Atherosclerosis.5
As the blood vessel walls thicken, the ability of the heart to pump the blood effectively decreases even further. Then, the pulsing of the blood against now-thickened artery walls increases the injury even further. When whole blood viscosity increases, it contributes to the formation of atherosclerotic plaque in the arteries.
In addition, blood viscosity directly modulates peripheral vascular resistance, the resistance to the flow of blood at the “farther reaches” of the vascular system. If blood flow is impaired due to increased viscosity, less oxygen and fewer nutrients can be delivered to the tissues and organs of the body, affecting critical areas such as the brain, eyes, and kidneys.
Another area that may be affected by blood viscosity is that of hearing loss, notably sudden deafness, or sudden sensorineural hearing loss. Studies have found a relationship between this type of hearing loss and insufficient blood flow (ischemia).6 Treatments that reduce blood viscosity may be beneficial in improving sudden sensorineural hearing loss.
Reduce your blood viscosity—and reduce your risk of heart attack and stroke
If your blood is too thick and sticky, you’re at unnecessary risk for heart attack and stroke until your blood viscosity becomes normal. Your blood isn’t delivering nutrients to your tissues as well as it should, either. There are two relatively certain ways to reduce thick blood to normal.
Educate yourself and your doctor on the No. 1 risk to your heart
Blood viscosity is the only biological parameter that has been correlated with all of the major cardiovascular risk factors including male gender, age, smoking, obesity, diabetes, hypertension, and LDL cholesterol. At the same time, blood viscosity is a much stronger biomarker for cardiovascular disease and is a statistically independent predictor of heart attack, stroke, and higher incidences of death. It is a useful indicator in atherosclerosis, and coronary, carotid, and peripheral artery diseases. Unfortunately, even physicians skilled and knowledgeable in natural and nutritional medicine are mostly unfamiliar—as I was—with the importance of maintaining normal blood viscosity in dramatically reducing risk of heart attack and stroke, as well as delivering nutrients to all the tissues. Hardly any mainstream physicians have been informed about it, either in medical school or by medical journals or patent medicine company representatives, since no patent medicines are approved for reducing blood viscosity. Every mainstream physician I’ve told about the potential 88-percent reduction in heart attack and stroke risk from just donating blood has been as unaware of it as I was. So you might want to tell your doctor about two very informative books about blood viscosity and atherosclerosis:
The Origins of Atherosclerosis, by Kenneth R. Kensey M.D. and Young I. Cho Ph.D. The Vulnerable Atherosclerotic Plaque, edited by Valentin Fuster, M.D., Ph.D. You read about one way at the beginning of this article—donating blood. And what could be better? You’d be doing yourself some good by lowering your heart attack and stroke risk, while doing someone else—the recipient of your donated blood—some good, too. How often you might need to donate blood, or if you need to at all to reduce your risk, can be determined by whole blood viscosity testing.
The other relatively certain way to reduce blood viscosity is to take fish oil (of course along with vitamin E as “mixed tocopherols,” which prevents damage from oxidized lipids). In the early years of research with fish oil, it was determined that if an adult took six tablespoons daily, there would be serious risk of bleeding out from even small cuts unless a very strong compression bandage was applied. It’s very, very likely that this is another rare circumstance in which whole blood viscosity testing would find the blood too thin. How much fish oil you personally need to normalize your blood viscosity can also be determined with whole blood viscosity testing.
The best measurement of cardiovascular health
The blood viscosity test monitors changes in the amount of solid materials in blood plasma. It gives you a complete picture of how the solid content in blood plasma, including cellular material, lipoproteins, immunoglobulins, and fibrinogen, among others, affects the blood’s ability to flow—its thickness and stickiness.
Knowing your blood viscosity can provide you with a good diagnostic evaluation of the efficiency and health of your cardiovascular system. Whether or not you are already diagnosed with atherosclerosis, knowledge of your blood viscosity will allow you and your doctor to make significant treatment decisions toward improving your quality of life and health outcome. And remember, it’s not only about the health of your cardiovascular system—it’s also about the ability of your blood to deliver nutrients to all of the tissues. The higher the blood viscosity, the less nutrient delivery downstream, and less oxygen transported from the lungs, upstream.
After reading all the research material about the importance of controlling blood viscosity to significantly reduce the risk of heart attacks and strokes, and to properly delivering nutrients throughout the body, I looked for a laboratory that could accurately test it.
Laboratories that routinely test for blood viscosity are hard to find, and even the few there are do a “single-point” viscosity test, which is not nearly as useful as tests that check multiple points on a curve, including the viscosity of the blood at both “systole” and “diastole.” (For the non-technically inclined, these are the peak point of blood output by the heart at maximum contraction, and the opposite, the low point at maximum relaxation.)
Dr. Holsworth contacted Health Onvector, the only firm that currently sells lab equipment capable of simultaneous multiple measurements of blood viscosity.
After a year of test validation of this lab equipment at Meridian Valley Laboratories (where I am indeed the Medical Director), the Whole Blood Viscosity test is now available for you and your doctor. Please contact Meridian Valley Laboratories (www.meridianvalleylab.com, 1-855-405-8378) for details.
If your blood is too viscous, you’ll cut your risk of heart attack and stroke by over 80 percent simply by donating blood!
Thanks to Lauren Russel, N.D., staff member at Tahoma Clinic, for assembling much of the data used in this article.
I don't know what causes viscous blood. I can tell you that I've been eating a 7.5 oz can of salmon nearly every weekday for a few months now and I bleed like an old man taking baby aspirin. One tiny scratch and thin blood will be dribbling down my arm or leg or even pooling up under my unbroken skin. It's a little disconcerting, actually.