Today’s column is the second in a series about major risk factors for heart attacks. A large majority of Americans develop artery-damaging hypertension as they age. High BP is called “the silent killer” because it doesn’t cause symptoms. Many who have it remain undiagnosed, and many who are treated continue to have blood pressures above ideal.

How is it defined?  Blood pressure consists of two numbers:  The upper (systolic) number is the pressure in arteries when the heart contracts; the lower (diastolic) number is the pressure when the heart muscle relaxes between beats. Large population studies show that the risk of heart attacks and strokes starts to rise when blood pressures are above 115/75. Heart attack prevention doctors feel blood pressure should be below 120/80, with the caveat that some older, frail patients do better with somewhat higher pressures.

How should blood pressure be determined?  The gold standard is to wear a 24-hour blood pressure cuff, that measures BP every 30 minutes or so, but it’s not practical for mass use. Many pharmacies have BP stations, but if you’re concerned about your BP the best option is to buy your own cuff (Omron is good brand) and check it morning, noon, and evening for a few days. Arm cuffs are more accurate than wrist cuffs, and come a size that fits the average arm. Special cuffs are available for adults with large or small-circumference arms and for children. Whether you check your own BP or a medical professional checks it, BP should not be taken over clothing. The cuff should be at heart level, and during measurement you should not cross your legs, chew, or talk.

What about “white coat hypertension?”  Some people say they have elevated blood pressure only when visiting the doctor (doctors used to wear white coats). Studies have shown that these people are at risk for the same health problems that people with sustained hypertension have, because their blood pressure goes up in other stressful situations that most people experience throughout the day. People with white coat hypertension are good candidates for 24-hour BP monitoring, or at least for frequent self-monitoring at home.

What causes hypertension?  Following are some of the causative factors:  1) obesity; 2) genetics; 3) the standard American diet, high in animal products, fat, sugar, salt, processed food, and added oil; 4) sleep apnea; 5) thyroid and adrenal disease; 6) chronic kidney disease; 7) some prescription drugs, such as steroids, certain anti-depressants, and estrogen; 8) over-the-counter medications such as NSAIDS  (ibuprofen, naproxen), and decongestants; 9) illicit drugs such as cocaine and amphetamines; 10) a few herbs such as licorice; 11) alcohol and alcohol withdrawal; 12) caffeine in some people; 13) sleep problems; 14) stress.

Why is high blood pressure dangerous?  In short, it damages arteries. It is a major risk factor for heart attacks; THE major risk factor for strokes; and is a major contributor to heart failure, chronic kidney disease, vision loss, dementia including Alzheimer’s, age-related brain shrinkage, damage to small blood vessels in the brain, erectile dysfunction, and aortic aneurysm rupture.

What we know about lifestyle and hypertension:  1) Early in the 20^th century, there were no medications for hypertension, and people (including F.D.R.) died from what was called “malignant hypertension”—BP above 220/120 or so. In the 1940s Dr. Walter Kempner put a group of these people on a strict salt-free rice and fruit diet, which brought BPs down to normal. 2) In countries on a Western diet blood pressures tend to increase with age. However, in societies such as the Blue Zones, where people are on a lifelong plant-based, whole food diet, blood pressures are the same at 90 as at 19. 3) When hypertensives are placed on such a diet, BPs often normalize. 4) Although BP goes up during exercise, regular, moderate daily exercise results in lower average BP.

Treatment:  In his book “How Not to diet,” Dr. Greger mentions the following foods as being particularly effective at lowering BP if consumed daily:  whole grains, ground flaxseed 1 tablespoon daily, hibiscus tea; legumes, and watermelon. Also helpful are foods that cause the endothelial lining of arteries to produce nitric oxide, which causes arteries to dilate, thereby lowering BP:  beets, greens, cilantro, basil, and rhubarb.

Lifestyle changes are cheap and free of side effects, but not everyone is willing to make them and occasionally they’re not enough. There are multiple medications to treat hypertension, and many have only rare side effects. If your BP is high, it’s important for optimal health to lower it to less than 120/80, one way or the other.

Dr. Greg Feinsinger is a retired family physician who started the non-profit Center For Prevention and Treatment of Disease Through Nutrition. For questions or to schedule a free consultation about nutrition or heart attack prevention contact him at gfeinsinger@comcast.net or 970-379-5718.