Monday 17 November 2008

Is Heart Disease caused by a nutritional deficiency?

There have been a number of articles in the past year which have highlighted the failure of cholesterol lowering drugs (Statins) to prevent heart disease in the general population. One article in the New Scientist was titled “US wasted billions on ineffective cholesterol drugs” and there was also the JUPITER trial in which the study found only a 0.25% difference in the mortality rate between the control group and the statin group. From these studies it appears that cholesterol lowering drugs are really only helpful for about 5% of the population suffering from hypercholesterolemia. But if Statins do lower blood levels of LDL Lipids and triglycerides, then why don’t they show any apparent benefit?

Searching through the various studies on the internet I found a number of things which do appear to prevent heart disease, nuts, for example, have frequently been shown to reduce the risk of coronary heart disease with 1 oz raw almonds per day reported to reduce risk of heart disease by as much as 50%. Then there are the whole grains, which reduce the risks by 40 percent, and beans also showed a reduced risk of 82 percent, amongst people who consumed them every day. Then you have dark green vegetables where more than two servings daily decreased the risk for heart disease by 46%. While the nurse’s health study showed that those who ate fish between two to four times per week reduced their risk by nearly 30%. So what do all these foods have in common?

Fish is meant to be good for the heart because of the Omega 3, but nuts especially almonds, contain virtually none in comparison to the very high levels of Omega 6 which get converted into inflammatory prostaglandins such as as PGE2 which cause inflammation. While the whole grains or the dark green vegetables only contain small amounts of the essential oils. The reason that dark green Vegetables are apparently good for the heart is the chlorophyll molecule which contains magnesium found to reduce the risk of the disease by 50%. Chlorophyll is very similar to haemoglobin; with the only real difference being the magnesium molecule that swaps places with the iron molecule in haemoglobin. Consequently green vegetables contain plenty of magnesium; spinach has on average 82mg of magnesium per 100g, while wheat bran contains as much as 600mg per 100g and brazil nuts 400 mg per 100g while soybeans contain about 300mg per 100g. Fish is no exception with cod, salmon and halibut containing about 100mg per 100g. Most other meats like chicken and beef contain only small amounts, between just 20 to 30 mg per 100g.

Another heart healthy component of chlorophyll is superoxide dismutase, a copper-containing protein also found in red blood cells. This enzyme decomposes superoxide radicals that can cause cholesterol to oxidize. In fact, oxidized fat’s and oxidized cholesterol are the only lipids found in arterial plaque. Before the 1970s studies with rabbits given cholesterol showed that they developed plaque in their arteries, but these studies used dried egg yolk containing oxidized cholesterol. When researchers repeated the previous experiments, they found animals fed normal cholesterol remained healthy. When you combine selenium from nuts with superoxide dismutase, you also get Selenium Superoxide Dismutase (SOD), the body's most powerful antioxidant enzyme. Brazil nuts contain the highest quantity of selenium at 1917mcg per 100g. Among more than 25 observational studies, researchers found that a 50% increase in selenium concentrations were associated with a 24% reduction in coronary heart disease risk. Another study of 1900 Finnish men looking at the effects of iron and the oxidation of blood lipids found that those with higher iron levels were more than twice as likely to have heart attacks. In fact, iron was a greater risk factor than excess cholesterol.

One of the other important nutrients found mostly in chlorophyll, and which seems to help prevent heart disease is vitamin K. The Rotterdam study revealed that an increased dietary intake of the vitamin could help reduce the risk of heart disease by 50%. In animal studies, vitamin K given to rabbits was found to decrease the concentration of circulating cholesterol. Foods which contain Vitamin K include kale 882mcg per 100g and spinach 541mcg. Most meat by comparison is limited to about 3mcg per 100g.

Another nutrient found to protect against heart disease and found mostly in nuts and legumes is the mineral boron. Legumes and nuts on average contain 1.0-4.5 mg boron per 100g, while other fruits and vegetables provide just 0.1-0.6 mg boron in every 100g. Since boron does not readily accumulate within animal tissues, meat and dairy products are poor sources of this mineral.

Fish contain some of the highest levels of another Vitamin reported to significantly reduce heart disease, vitamin D. Salmon for example has 763IU of vitamin D per 100g. Cheese By comparison contains only contains 40IU. In one study, people with low levels of vitamin D were found to be 220% more likely to suffer heart disease, compared to patients with the highest levels. Vitamin D not only helps transport calcium into the bones but is also involved in its absorption. Calcium enters special intestinal cells which then use calcium binding protein containing vitamin D to transport it through the blood stream.

Magnesium, vitamin K, boron and vitamin D, are all involved in the transport of calcium from the blood into the bones. So it would appear that these nutrients significantly reduce your risk of heart disease because they reduce the levels of calcium ions within the blood stream. The plaques found in the arteries of heart attack victims consist of 95% calcium and only 5% oxidized LDL. But this isn’t the same Calcium attached to the calcium binding protein from your diet, instead the calcium ions are leached from the bones as the body attempts to neutralise acids. These Calcium ions have a positive charge, which then bond to the oxidized and negatively charged Lipids (Cholesterol). Excess calcium ions within the blood vessel walls also cause them to constrict, leading to high blood pressure. This happens because the calcium Ions stimulate muscle fibers causing the blood vessels to tense and contract, while Magnesium is needed to pump the Calcium Ions back out so the blood vessels can relax. If the concentration of Calcium within the blood is very high, then these pumps have to work extra harder to keep the Calcium out. Calcium-channel blockers can help lower blood pressure by preventing the calcium from entering the cells and leaving it in the blood stream, but you have to keep taking them. The only effect way to cure both high blood pressure and hart disease is to include the nutrients in the diet needed by the body to remove these calcium ions from the blood stream. For example, Researchers investigating the association between vitamin D, and blood pressure, found that people with lower blood levels of vitamin D gained a 20 percent increases in systolic blood pressure as they aged than did those people who had healthy levels.

While levels of the nutrients in the diet needed to keep the calcium within our bones have been declining levels of compounds like phosphoric acid which leach the calcium out of the bones have been on the rise. Epidemiological studies have also linked phosphoric acid found in fizzy/carbonated drinks like Coca Cola to lower bone density. A study on children also found that the more Cola they consumed, the more calcium there was in the blood. With other studies finding a connection to children with kidney stones. Given the recent studies which found obese children to have arteries like those of men over 45, it wouldn't be surprising if phosphoric acid did contribute to Hart Disease. High consumption of animal protein has often been linked to heart disease but whether this is due to the high acidity of the sulfur based amino acids which are well known to leach calcium from the bones, or because the main sulphur based amino acid methionine is continually recycled back into homocysteine which then oxidizes blood lipids and has long been associated with heart disease, requires more research.

If oxidized lipids and calcium ions cause Hart Disease, then why do so many studies show a strong relationtionship to the inflammatory markers like C-Reactive Protein and weight gain on the abdomen? This fat which develops around the abdomen is named visceral fat and also surrounds the vital organs, while the subcutaneous fat is the type found just underneath the skin. Some visceral fat is necessary, acting as a cushion between organs and as a defence mechanism to store acidic waste and toxins. In order to find the connection between this visceral fat and atherosclerosis, scientists transplanted clusters of visceral fat cells into healthy mice. As this fat became inflamed it attracted a type of immune cell called macrophages, while transplants of subcutaneous fat didn’t, despite still causing inflammation. In the mice with the visceral fat transplants the mice developed atherosclerosis, which appeared to be due to the Macrophages, since the subcutaneous transplants of fat didn’t cause any atherosclerosis. So why do these Macrophages cause atherosclerosis?

Macrophages are a form of large white blood cell normally formed deep within bone marrow, spleen, and lymph nodes which circulate within the blood to clear up bacteria, and other foreign invaders. More than 90 percent of the macrophages in adipose tissue of obese people are located around dead fat cells, which the immune cells appear to be mopping up? Macrophages also have scavenger receptors which recognize, bind, and internalize modified forms of LDL such as the acetylated and oxidized forms. This process leads to the formation of so-called foam cells which are lipoproteins with a strongly enhanced negative charge; this enables them to bind with the positively charged calcium ions, and form the plaques in atherosclerosis.

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