Hypertension
Blood pressure is simply the amount of force exerted when blood pushes against the walls of the blood vessels. High blood pressure, or hypertension, is when there is too much pressure on the vessel walls that makes the heart work very hard to push blood through tighter arteries. Over time, high blood pressure weakens the heart and causes hardening of the artery walls, making them weak and susceptible to injury. Often, hypertension has no symptoms whatsoever, but this damage to the blood vessels or heart, may lead to stroke, heart failure, heart attack, kidney failure, and vision loss. This is why hypertension has the infamous nickname, the silent killer (1).
Have you heard that reducing sodium can lower blood pressure? Well that is true for a lot of people (2)! Sodium is found in a lot of foods in small amounts, but it makes up about 40% of table salt. It is necessary for the body in very small amounts, but most Americans eat entirely too much. So how does sodium increase blood pressure?
Sodium is always carried in solution in the body, so when it passes from the digestive tract to the blood vessels, it carries fluid with it. Normally, the vessels are fairly elastic, like the walls of a balloon. However, the extra fluid carried with sodium increases blood volume. Just like adding water to a balloon, this causes the vessel’s diameter to stretch and makes the vessel walls taut with pressure. Over time, this increased pressure inside the arteries may cause hardening of the artery walls and lead to permanent damage. Learn more about hypertension by visiting the website of the American Heart Association at http://www.americanheart.org.
So, if you are mildly salt sensitive, lowering your sodium intake below 2300 mg per day (the amount of sodium in about 1 teaspoon of table salt), can have a major impact on your blood pressure. The Dietary Approaches to Stop Hypertension, or DASH diet from the National Heart, Lung, and Blood Institute, recommends that Americans with hypertension consume an even lower 1500 mg of sodium, in addition to other positive lifestyle changes (3). In research done with the DASH diet (DASH Sodium Trial), after just 8 weeks of decreasing sodium, participants saw a decrease in blood pressure! For more information about the heart-healthy DASH diet, visit the National Heart, Lung, and Blood Institute’s website at http://www.nhlbi.nih.gov/hbp/index.html.
For most people, lifestyle changes will have a positive outcome on blood pressure. By following an exercise plan prescribed by your doctor, eating more fruits and vegetables, decreasing sodium while increasing potassium, and losing even 10% of your body weight if you are overweight, may reduce blood pressure (4). These are great reasons to add pears to your diet! Pears are sodium-free, fat-free, contain antioxidants and 190 mg of potassium, and when they replace higher calorie foods in the diet, may aid weight loss! Just think, if you replace high-sodium, high-calorie foods in your diet with low-calorie, sodium-free foods such as pears, you’ll decrease your sodium intake even more!
1. American Heart Association, Hypertension. Available online here.
2. American Heart Association, Make Healthy Food Choices to Stop Hypertension. Available online here.
3. National Heart, Lung, and Blood Institute, Lowering Your Blood Pressure with DASH. Available online here.
4. American Heart Association, High Blood Pressure – What Can Be Done? Available online here.
Findings
Need to decrease hypertension? Start with fruits and vegetables!
In 1,569 (642 men, 927 women) subjects in Ohasama, Japan, high-level consumption of fruits and vegetables was associated with a significantly lower risk for hypertension. Likely due to their antioxidant properties, there was a strongly significant association between high potassium and vitamin C intakes and a lower risk for hypertension. Vitamin C has a strong correlation with high levels of fruit and vegetable consumption, and thus, a high vitamin C intake seems to contribute to lower blood pressure. However, this is not the case with vitamin C supplements. Only vitamin C found in fruits and vegetables had a benefit, likely due to a combined and synergistic relationship at work between vitamin C, antioxidants, and phytochemicals. Compared to those consuming the least amounts of fruit daily (15.6 grams/day), those consuming the most (222.7 grams/day) had a 45% lower risk of hypertension!
Utsugi MT, Ohkubo T, Kikuya M, Kurimoto A, Sato RI, Suzuki K, Metoki H, Hara A, Tsubono Y, Imai Y. Fruit and vegetable consumption and the risk of hypertension determined by self measurement of blood pressure at home: the Ohasama Study. Hypertension 2008;30(7):1435-1443.
This site is for informational purposes only, and is not intended to treat any illness or condition. If you have questions or concerns about your health, seek advice from your physician.