According to the National Institutes of Health, most people in the United States have high blood pressure at some point in their lives. Hypertension, the medical term for blood pressure that remains elevated over time, doesn’t have any symptoms, so people may not even know they have it. Left untreated, it can affect the ability to think, learn, and remember. It can also lead to blindness, kidney failure, heart failure, heart attack and stroke.
The most common treatment is medication and 68 percent of US adults take blood pressure-lowering drugs. But other effective interventions exist. Changes in diet and lifestyle that address underlying factors can lower high blood pressure and improve overall health.
Salt
People with hypertension are advised to eat a low sodium diet, but studies show that it doesn’t really make a difference. The well-respected Cochrane Collaboration is an independent, not-for-profit organization that reviews research studies relating to health care and is internationally recognized for its evidence-based standards.
In 2004 Cochrane researchers reviewed 57 studies of people with normal blood pressure (120 mm Hg systolic over 80 mm Hg diastolic, or lower) and 58 studies of people with elevated blood pressure. All of the participants were randomly assigned to either a low sodium diet or a high sodium diet.
Individuals with normal blood pressure who ate a low sodium diet experienced only slightly lower blood pressure readings. Their systolic pressure only dropped one point (mm Hg) and diastolic pressure didn’t even drop half a point. In people with high blood pressure, low sodium diets made more of a difference but the results were still insignificant. Systolic pressure went down four points and diastolic dropped less than two points.
Researchers noted that compared to Caucasians, black and Asian people received slightly more benefit from the low sodium diet (a reduction of up to six points systolic) but they still concluded that low sodium diets are not warranted.
Sugar
Instead of salt, people with high blood pressure should avoid sugar. Or more specifically, foods that contain easily digestible carbohydrates like sugar, flour, white rice, potatoes, juice and beer. The carbohydrates in these foods are quickly digested and absorbed into the bloodstream, flooding the body with glucose.
High blood glucose, the medical term for high blood sugar, causes the body to retain water, which can increase pressure inside blood vessels. Studies have linked high blood sugar to high blood pressure and demonstrated that lowering blood sugar also lowers blood pressure.
High blood sugar damages blood vessels. It causes excessive amounts of compounds called advanced glycosylation end products (AGEs) to be produced. AGEs can slowly accumulate in the body and bind together in a process called cross-linking. When cross-linked AGEs accumulate in tissues, they cause rigidity and interfere with normal structure and function. Collagen, a fundamental component of blood vessels, is particularly susceptible to cross-linking, which causes vessels to stiffen and blood pressure to rise. Once blood vessels lose their elasticity, they can no longer effectively regulate blood pressure.
Blood Pressure-Lowering Diet
Unlike simple carbohydrates, the complex kind are bound to fiber, protein and fatty acids. Because they are digested and absorbed slowly, not all at once, they cause blood sugar levels to rise only gradually.
Complex carbohydrates are found in whole plant foods like fruits and vegetables. Plant foods should make up 75% of meals, with the remaining 25% composed of protein like meat, seafood, eggs, pre-soaked slow-cooked beans, tofu or tempeh. Avoid animal products that come from animals fed grains or exposed to pesticides, antibiotics or hormones.
Eliminate easily digestible carbohydrates from your diet, including processed foods, bread, pasta, pretzels, crackers, cookies, candy, cake, pastries, pancakes, waffles, white rice, potatoes, milk, beer, juice and sweetened beverages.
If you want a sweet treat, choose dark chocolate. It's low in sugar and high in cocoa powder, which contains antioxidant polyphenols that support healthy blood vessel function. Limit yourself to one or two ounces per day and look for chocolate that is 70 to 85 percent dark (the darker the better). Because alkalizing agents destroy antioxidants, avoid products with alkalinized or Dutch-process cocoa powder.
Lifestyle
Other essential lifestyle interventions for lowering high blood pressure include stopping smoking, avoiding alcohol, maintaining healthy levels of vitamin D, staying active, and managing stress.
Stress hormones can raise blood sugar levels because they activate the sympathetic nervous system, our inherent “fight or flight” response to stress. This survival instinct prepares the body for action by increasing heart rate and blood pressure, and raising sugar levels in the blood. Activities like meditation, yoga, tai chi and breathing exercises have the opposite effect. They reduce sympathetic stimulation, promote relaxation and lower blood pressure.
Exercise isn’t just a workout for muscles and bones, it’s a workout for the heart and blood vessels too. Regular exercise is the best way to maintain healthy blood vessel function and healthy blood pressure. It also improves coordination, balance, flexibility, energy, sleep and mood. According to a study published in the
New England Journal of Medicine, regular exercise can even add an extra year or two to your life of life. However, people with cardiovascular disease including high blood pressure should get permission and guidelines from their doctor before they begin a new exercise program.
Because low levels of vitamin D are associated with high blood pressure, it should be supplemented in people who have documented deficiencies. Vitamin D can accumulate in the body, so it’s important not to take too much. A blood test should always be done to determine whether levels are low and how much is needed.
Other supplements can be helpful for hypertension, but some have dangerous interactions with prescription medications. Always get individualized recommendations from your doctor before taking a new supplement.
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Inoguchi T et al. High glucose level and free fatty acid stimulate reactive oxygen species production through protein kinase C--dependent activation of NAD(P)H oxidase in cultured vascular cells.
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Jürgens G and Graudal NA. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterols, and triglyceride. Cochrane Database of Systematic Reviews. 2004;(1):CD004022.
Ostchega Y et al. Hypertension awareness, treatment, and control--continued disparities in adults: United States, 2005-2006. National Center for Health Statistics Data Brief. 2008 Jan;(3):1-8.
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Like Andrea Reusing's acclaimed restaurant Lantern, her book, Cooking in the Moment, celebrates local and seasonal ingredients.
