This third part of Dr Ed's article on preventing, stopping, and even reversing atherosclerosis, offers the first two steps in a program that you can undertake, starting today . . . . .

To read all the articles in the series, you can go to the mini-site: "Aging of Your Heart and Blood Vessels is Risky" by clicking here .

How to Promote and Maintain a Healthy Endothelium

* Step 1: Reduce Modifiable Risk Factors

Removing or reducing modifiable risk factors for atherosclerosis helps prevent injury to the endothelium and promotes repair of damage already done. Modifiable risk factors are: smoking, diabetes, high cholesterol, high blood pressure, obesity, a sedentary lifestyle and stress.

Smoking reduces nitric oxide in the blood vessels and causes an increase in ADMA, the modified amino acid which opposes the action of L-arginine in the body. This is caused by the free radicals in the smoke. Smoking raises the level of carbon monoxide in the blood, which increases the risk of injury to endothelial cells. Smoking increases blood pressure and heart rate, putting additional strain on the heart. Nicotine also causes vessels to narrow, so that less oxygen is delivered to the heart. Platelets become stickier, and therefore clot formation is increased.

The endothelium in persons who have diabetes makes too much of a substance called superoxide anion, one type of free radical, which, at high levels, destroys nitric oxide.

Hypertension, as discussed earlier, causes the vessels to thicken. Clot and atherosclerotic plaque formation is promoted and the production of nitric oxide is impaired.

Common medical conditions interact to damage the endothelium. Obesity carries with it the high probability that it will be accompanied by high blood pressure. Obesity can also lead to insulin resistance, which means that the body has to produce excess amounts of insulin to keep the blood glucose within normal limits. High insulin levels are linked to the development of hypertension. Obesity also increases the probability for high blood triglycerides and a low HDL (the 'good' cholesterol).

A sedentary lifestyle is detrimental to your endothelium because it promotes obesity, which increases the probability of insulin resistance and hypertension, high LDL cholesterol and decreased HDL cholesterol levels.

Emotional stress causes adrenaline (epinephrine) to be released from the adrenal gland and nor-adrenaline from the nerve endings in your heart and blood vessels. This is a sympathetic nervous system response which makes the heart rate increase, promotes clot formation and constricts the blood vessels. As discussed earlier, stiffer vessels also make the heart work harder.

One can see that these risk factors don't operate in isolation. They interact with one another to destroy the endothelium in addition to other dire effects. The more risk factors involved the more serious the outcome. Endothelial damage is therefore a powerful predictor of present and future myocardial function.

* Step 2: Maintain a Heart Healthy Diet

Scientific studies have shown us a lot concerning the relationship between endothelial health and diet. First, fat matters . The chemical properties and metabolic effects of fats are very different. This difference is why saturated fats are atherogenic ¹ while unsaturated fats do not promote atherosclerosis or raise cholesterol levels.

Fats are made up of carbon and hydrogen molecule chains of varying lengths. A fat is considered saturated if all of the available carbon molecules have hydrogen on them. This chemical structure causes saturated fats to be solids at room temperature. A fat is considered unsaturated if it has one (mono-) or more (poly-) carbon-carbon "double bonds". This double bond changes the chemical properties and causes these fats to be liquids at room temperature.

Hydrogen molecules can be bubbled into an unsaturated oil to make it chemically like a saturated fat, a food process called "hydrogenation". This extends the shelf life of the product and makes the fat more solid at room temperature. The down side to this is that trans fatty acids are formed during this hydrogenation process. Some scientists believe the trans fats are more damaging to the heart than saturated fats.

Butter contains 66% saturated fat and can contribute to raising blood cholesterol and promoting plaque formation on our arteries, contributing to heart disease. However, margarine is not much better. While not having the saturated fat of butter, margarine contains trans fatty acids, formed during the hydrogenation process, which research shows can also raise cholesterol. Therefore, look carefully at food labels for saturated fat, but also avoid processed foods as trans fatty acids are frequently in these. but are disguised by being labeled as 'partially hydrogenated oil'.

Endothelial function temporarily deteriorates to about half of normal within about two hours after a high saturated fat meal, even in healthy young persons with no risk factors for atherosclerosis. Monounsaturated and polyunsaturated fats are therefore better for the endothelium than saturated or trans fatty acids, and should replace these atherogenic fats in your diet.

Monounsaturated fats come from plants. Sources are oils, such as olive, peanut and canola oil, nuts, olives and avocados. Polyunsaturated long chain fats include omega-3 and omega-6 fatty acids. Omega-3 fatty acids are found in fish, nuts, dark leafy vegetables, and flaxseed. Omega-6 fatty acids are found in oils such as corn, sunflower, soybean, and sunflower.

Omega-3 fatty acids may be especially important in improving endothelial function. Recently, the scientific community has been concentrating on the benefits of these fatty acids. The most important fish oil fatty acid is one called docosahexaenoic acid (DHA). We have long known that fish is healthy, but it is now proven that the omega-3s in fish fat improve endothelial function by enhancing NO production, increasing HDL cholesterol levels and reducing LDL and triglyceride levels. Further, fish oils have been shown to reduce production of free radicals and substances that cause inflammation in the body. But don't just eat any fish. Did you know that salmon has 10 times the amount of omega-3 fatty acid as flounder? Herring has almost 16 times the amount. And mackerel has almost 27 times the amount.

There are several great plant sources of omega-3 fatty acid as well. Flax is a plant with blue flowers; its seeds yield linseed oil and from its stems a fine, light-colored textile fiber is obtained. Flaxseed is a superior source of omega-3 fatty acid, containing almost 33 times the amount of omega-3 fatty acid as wheat germ.

Second, protein matters. Replace animal proteins with vegetable and soy proteins. Animal proteins contain mixtures of aminoacids that produce more of the aminoacid methionine, which is the precursor for homocysteine, which can damage the endothelium. Vegetable proteins are healthier because they contain no saturated fat and less methionine. Vegetable proteins also have more fiber and nutrients, called phytonutrients. Soy proteins produce a mixture of aminoacids that have more L-arginine. Recall that L-arginine is essential for the production of NO, the gas that's critical for endothelial health. Soy proteins also contain other phytochemicals, the biochemical products of plants, which are healthy for the endothelium. Look for other L-arginine protein sources, as well. These include fish, nuts, legumes, beans and chicken.

Third, carbohydrates matter. Simple carbohydrates are individual molecules of glucose. Complex carbohydrates consist of chains of glucose molecules. This chemical difference influences the way they are metabolized. Simple sugars break down quickly, increasing the blood sugar. This causes an insulin surge to be released by the pancreas, which promotes the deposition of fat. Complex carbohydrates are broken down one at a time, so they don't cause a big increase in insulin. In addition to these differences, complex carbohydrates tend to contain other nutrients such as vitamins and minerals as well as dietary fiber, while simple carbohydrates tend to have little nutritional value. But there is a caveat here. Eating too much complex carbohydrates can make you fat just as easily as eating simple sugars, and although still controversial there are scientific studies which support the principles upon which the controlled carbohydrate nutritional approach (or Atkins Diet) are based. Many respected scientists have acknowledged that this approach to weight control and healthy living is a subject that, based on the very positive results of recent studies, deserves further study.

Fourth, B vitamins promote healthy blood vessels. They help keep homocysteine levels in the body low. As previously stated, high homocysteine levels damage vessels. Good sources of B6 are salmon and chicken. Good sources of B12 include shellfish and poultry.

Fifth, eat plenty of fruits and vegetables. These contain antioxidants, including vitamin A, vitamin E compounds, vitamin C and polyphenols which detoxify free radicals. Antioxidants are agents that combat the biological damage caused by free radicals. Free radicals damage by oxidation, similar to rusting. Research has demonstrated that antioxidants neutralize them, inhibiting the mutation and carcinogenic action of free radicals as well as stopping them from creating the chain reaction that contributes to various diseases, including premature aging and cancer. You have natural antioxidants but the effectiveness of these declines with aging. Therefore, supplements in older persons should be a consideration, along with increasing dietary intake.

Sixth, get plenty of fiber as a dietary aid. Insoluble fiber, as found in nuts and wheat, slows down digestion and helps dieters by making them feel satiated for a longer period of time. Decreasing body fat and combating obesity is healthy for the endothelium. Soluble fiber, found in grains and plants like beans and legumes, has been shown to reduce blood cholesterol levels, which is also healthy for the endothelium.

Control caloric intake to help prevent obesity, but eat those foods which manufacture nitric oxide to maintain a healthy endothelium, or heal an unhealthy endothelium and reverses the process of atherosclerosis.

Part Four of this article will discuss steps three and four of this program, use of medications and supplements and the part exercise plays in promoting endothelial health.

Dr. Ed is a physician/scientist, who is internationally recognized for studies that range from humans to molecules on how the heart and blood vessels work in health and disease as the body ages.

Links

• To read all the articles in the series, click here
• You Can Prevent and Roll-Back Atherosclerosis, and Decrease Your Risk for Heart Attack and Stroke - Article XV (Part 1 of 4)
• Nitric Oxide and Vascular Health - Article XV (Part 2 of 4)
• Women at Cardiovascular Risk
• Which is More Important - the Upper or Lower BP Number?
• What's the Best Diet For Preventing Heart Disease?

Footnotes

1. Atherogenic - having the capacity to initiate, increase, or accelerate the process of atherosclerosis