HYPERTENSION: STALKING SOCIETY’S SILENT KILLER
Hypertension (HTN) or High Blood
“The Silent Killer”
This is because it often occurs without accompanying symptoms. Yet, it significantly increases the risk for stroke, heart disease, kidney failure, and impaired memory. Approximately 60% of Americans over the age of 65 will develop hypertension.
Physiology of Blood Pressure
Blood pressure is the force that drives the blood through the blood vessels. It is determined by how much blood the left ventricle of the heart pumps per minute (cardiac output) multiplied by the resistance to blood flow. Without the normal amount of resistance to blood flow in the arteries, we would become light-headed and prone to fainting. It is when this resistance becomes too great that hypertension develops. As arteries constrict, the resistance to blood flow increases and blood pressure goes up.*
Certain lifestyle conditions and practices inevitably lead to high blood pressure. Correcting harmful dietary habits can prevent and often help to reduce hypertension.
- Limit salt intake. Approximately 40% of hypertensive individuals have a natural tendency to retain salt in their bodies. Excess salt and sodium consumption promotes fluid retention and causes the arteries to become more sensitive to norepinephrine, an artery-constricting hormone.1, 2, 3 Studies show that a high salt diet gradually thickens and stiffens arteries.4 However, a modest amount of salt is essential for a healthy functioning nervous system. Mild salt restriction generally works much better for lowering high blood pressure than severe salt restriction. One teaspoon of salt contains 1200 milligrams of sodium. Most Americans consume over 4000 milligrams of sodium each day. Hypertension is rare in countries where less than 2000 milligrams of sodium is included in the daily diet. To keep your salt within normal levels: Avoid processed foods like chips, pickles, and canned goods. Limit eating out at restaurants.
- Limit calories if overweight. Why? The arteries in an obese individual become more sensitive to molecules that constrict them and less sensitive to molecules that open them.5, 6 In fact, extra fat cells (adipocytes) produce hormone-like chemicals that promote inflammation in the arteries. Extra adipocytes also create more trouble for the arteries by producing a precursor to angiotensin II, a powerful blood vessel constrictor.7 Both obesity and hypertension gradually cause the left ventricle of the heart to enlarge, making it more sensitive to arrhythmias (electrical disturbances in the heart’s rhythm). They also damage the kidneys by several mechanisms.8 Among other serious consequences, diabetes and obesity decrease the ability of the innermost lining of the blood vessels to manufacture molecules that enable the blood vessels to dilate and discourage undesirable clotting. Just a weight loss of even 10% in obese individuals is helpful in reducing high blood pressure and lowering blood lipids (cholesterol and triglycerides). Exercise and weight loss improve the ability of the blood vessels to dilate in type 2 diabetes.9 This is encouraging news because diabetes and hypertension often accompany each other.
- Avoid oxidized cholesterol because it promotes inflammation in the arteries and hardening of the arteries that contributes to the development of hypertension. Oxidized cholesterol, which is found in aged cheese, powdered dairy milk, dairy puddings, and custards, encourages inflammation. Learn to make vegetarian cheese and carob pudding. Gradually substitute soy, rice or nut milk for dairy milk.
- Avoid caffeine because it increases the consumption of oxygen in the brain and blood flow resistance in the cerebrum (upper 7/8th of the brain). In other words, caffeine increases the demand for oxygen in the brain while reducing the supply of blood flow within the brain.10 This can severely damage brain cells that are already compromised by hypertension.
- Substitute legumes and nuts for meat. Legumes and nuts, unlike meat, do not contain cholesterol and saturated fat, but instead are rich in fiber. Regular consumption of legumes helps to reduce high cholesterol levels (high blood pressure pushes cholesterol into the arteries).11 Both legumes and nuts are rich in the amino acid arginine, the precursor to nitric oxide. In moderate amounts arginine helps to reduce inflammation and improves dilation in the arteries. Consumption of soybeans also helps to keep the arteries elastic.12
- Limit your intake of sugar, fructose corn syrup, and soft drinks. A diet high in sugar and fructose corn syrup can lower the threshold for hypertension. Interestingly enough, these products also raise uric acid, a byproduct of protein metabolism. Elevated uric acid levels are associated with new cases of recent-onset-essential-hypertension in children, and predict non-alcoholic fatty liver disease in obese children.13, 14 Beware, then, of soft drinks containing fructose-derived corn syrup. It is much better to enjoy fructose in whole fruits where it is packaged with fiber.
- Eat fresh or frozen green vegetables every day.15 These contain magnesium, which helps to prevent the blood vessels from experiencing sustained contraction, called vasospasm. Some studies show that eating three stalks of celery a day can reduce elevated blood pressure levels.16, 17 Broccoli and spinach contain the antioxidant and phytochemical, alpha-lipoic acid, which also helps to reduce high blood pressure and oxidative stress in hypertensive individuals.18, 19, 20 Alpha-lipoic acid also helps to reduce the oxidative stress that is seen in hypertension.
- Eat five servings of fresh or frozen fruits and vegetables every day. Abundant consumption of fruits and vegetables, potassium, and vitamin C is associated with a significantly lower risk of hypertension.21 Increased fruit and vegetable intake improves the ability of the blood vessels to dilate in hypertensive individuals.22, 23 Fruits and vegetables are rich in potassium, a mineral that protects the arteries and kidneys and reduce the risk for stroke. Vegetarians have less incidence of hypertension than omnivores and a vegetarian diet can reduce elevated blood pressure.24
Exercise and Blood Pressure
Regular mild aerobic exercise helps to keep the arteries elastic and makes them less sensitive to the vasoconstrictive hormones, epinephrine and norepinephrine. Low to moderate-intensity exercise can improve the ability of the blood vessels to make vasodilating molecules. Extreme, exhaustive exercise, though, not only increases the risk for undesirable clotting, but also increases angiotensin II.
Who is in Your Driver’s Seat?
The health of leaders shapes the history of their country and people. Woodrow Wilson was inaugurated as President of the United States in 1913 and served as President during the First World War. Edwin A. Weinstein’s book, Woodrow Wilson: A Medical and Psychological Biography, reveals some interesting facts, some of which are very applicable to this lecture. Largely unknown at the time of his campaign, Wilson had been plagued by hypertension and mild strokes. In 1896 Wilson possibly experienced his first stroke which caused marked weakness of his right upper limb plus sensory disturbances in his fingers. His doctors at the time diagnosed him as having neuritis. In June of 1904 Wilson developed weakness in the right upper limb that lasted for several months.
Once President, Wilson’s problems still persisted. In May of 1914 changes in the arteries of his eye were documented. Wilson experienced severe headaches lasting for days during the years 1915-1919. Wilson desperately wanted the First World War to be the war that ended all wars. If Wilson had been in better health, could he have initiated a more equitable peace treaty so that the seeds of the Second World War would not have been planted? While campaigning for the League of Nations, Wilson suffered his stroke. Would the League have succeeded if Woodrow Wilson had been well at that time? We really don’t know, but Wilson’s condition leaves some interesting questions for us to address individually.
Wilson suffered a catastrophic, disabling stroke while President on October 13, 1919. His wife and physician conspired to keep the extent of his disability a secret; indeed, Wilson’s condition was hidden from his own Cabinet, from the Vice President and, of course, from the public. So who was running the government?
In what ways exactly does our cardiovascular health impact our community? In Wilson’s day the medical community did not know as much about how to prevent and treat hypertension. Are we taking advantage of the opportunities that we personally have to follow the lifestyle principles that modern medical authorities advocate—to lose weight if obese, watch the salt, and exercise? Will our usefulness be cut short by our negligent failure to do so? Will cardiovascular disease sabotage our plans to help our world or to guide a child we love? If that happens to you, who will be in your driver’s seat?
*Of course, other factors influence blood pressure and can contribute to hypertension (i.e. increased sympathetic tone, increased cardiac output, increased viscosity of blood).
By Elizabeth Hall, physiology instructor and health researcher at Wildwood Lifestyle Center & hospital, GA
Original article retrieved from: http://www.how-to-be-healthy.org/hypertension-stalking-society%E2%80%99s-silent-killer/
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