Hypertension is defined as the chronic disease characterized by elevated blood pressure (over 120/80 mmHg). The force exerted on your arterial walls is called blood pressure. Nutrition is the key factor behind obesity, which is an ongoing pandemic in the United States. The key cause behind obesity is poor nutrition coupled with a sedentary lifestyle. A Framingham heart study showed that 65-75% of the risk for hypertension can be directly attributed to excess weight (Hall, 2003).
Obese individuals have an increased amount of body mass. This extra amount of adipose tissue increases flow resistance and requires more blood and oxygen throughout the body (Hall, 2003). This increase in demand of blood flow causes a rise in cardiac output and a subsequent rise in blood pressure. Weight specific to the abdominal area can be especially problematic because this type of fat causes arteries to thicken and harden (Hall, 2003). Moving blood through these vessels is more difficult, further increasing blood pressure.
The increase in adipose tissue causes abnormal kidney function as well. Obesity causes the renal medulla to become compressed in the kidneys and contribute to chronic kidney disease. Adipose tissue almost completely surrounds the kidneys and even penetrates the medullary sinuses (Hall, 2003). This causes an increase in tubular reabsorption of sodium due to reduced blood flow in the loop of henle. An increase of sodium in the diet can further elevate serum sodium levels. The influx of sodium into the bloodstream causes serum sodium levels to become elevated. Extra sodium in the body results in an increase of water, the body’s response to flush out the sodium (Hall, 2003). All of this extra water is absorbed into the blood vessels, increasing the blood volume inside of the capillaries, resulting in hypertension.
Nutrition choices made by individuals can be a leading factor that may put them more at risk for developing hypertension. Sodium specifically, is typically the first part of diet that comes
to mind with hypertension. Increased sodium in the diet causes the body to try to “flush” out the sodium, so as a result the body holds onto water. The water that is held in the body enters into the bloodstream and increases the pressure in the arterioles (Graudal, Graudal & Jurgens, 2011). Food that are high in sodium include breads, pizza, cheese, salad dressing, cake/pie, and deli meat; these foods should be limited in the diet.
Another essential part of a person’s diet is potassium. Potassium has the opposite effect of sodium. Potassium lowers blood pressure by relaxing vascular smooth muscle (Treasure & Ploth, 1983). Decreased potassium in the diet can lead to signs and symptoms such as muscle cramps, palpitations, but more importantly the low potassium intake results in a failure to counteract the negative effects of sodium (Treasure & Ploth, 1983). Potassium rich foods include fresh fruits and veggies, meats, and juices; these foods should be sought after in a daily diet.
High fat intake can have negative effects on the body and may lead to hypertension. Fat is essential to the body because it provides insulation, helps absorb fat soluble vitamins, and provides energy to the body when carbohydrate stores aren’t able to be utilized. Fat is important, but when taken in excess through an individual’s diet it can become problematic. Too much fat in the diet can lead to increased blood lipid levels, ultimately leading to atherosclerosis (Balch, Splitter, Flynn & Kinsell, 1958). Atherosclerosis is the narrowing of the arterial lumen caused by plaque buildup in blood vessels. Some examples of high-fat foods include sugary drinks, candy, deep fried food, cakes, and alcohol; these foods and drinks should be limited in a patient’s diet.
It is important to note that there is no current cure for hypertension, though there are ways to combat the symptoms through lifestyle changes such as diet modifications. The nutritional needs for those diagnosed with hypertension is outlined in the Dietary Approaches to
Stop Hypertension (DASH) diet. This diet is recommended by the American Heart Association and the National Cancer institute and according to Anderson, Young, and Long (2008), it “focuses on what people should eat, rather than what not to eat” (p. 2). It was found that those following the DASH diet saw a significant decrease in their blood pressure, “as much or more than any anti-hypertensive medication had been able to” (Anderson, Young, and Long, 2008, p. 2).
The DASH diet concentrates on reducing daily intake of fat, cholesterol, and sodium. It aims to reduce the intake of sodium because as mentioned above, exorbitant amounts of sodium intake has been linked to hypertension. It also encourages a diet high in fruits, vegetables, low-fat dairy products, and complex carbohydrates. This provides a diet rich in potassium, magnesium, and calcium which Anderson, Young, and Long believes is somewhat responsible for the decrease in blood pressure. This may be due to the fact that potassium plays a vital role in blood pressure management by keeping the body’s water balance in check. Calcium is also important because a lack of calcium may raise one’s risk of hypertension.
Knowing how important nutrition is to someone with hypertension, a nurse must take special considerations when caring for a patient with hypertension. When assigned a patient with hypertension, the nurse should educate the patient about what food or drinks are best to eat to help combat their disease. A common diet plan to educate the patient about is represented by the aforementioned DASH diet, which stands for Dietary Approaches to Stop Hypertension. It is important to implement education on this diet plan because it is created for people who need to actively partake in lowering their blood pressure.
When educating a patient on how to begin a DASH diet it is important to remind them to make a gradual transition into their new diet plan. When a patient does not gradually move onto
the new diet it may increase the chance of them not following the new plan all together. For a gradual change, one may advise the patient to add a serving of vegetables at lunch one day and then the following day begin adding vegetables to dinner as well (DASH, 2015). There is more to a DASH diet than just adding vegetables though, a patient following this diet plan should also limit their lean meat intake to 6 ounces a day. One way to do this is to have the patient compare their lean meat to a deck of cards. With a serving of meat that size, it should be about 3 ounces, which will also allow the patient to have another serving of lean meat later in the day (DASH, 2015).
Other considerations for a patient with hypertension is to encourage exercise. Along with the DASH diet plan, a patient can decrease their blood pressure even further by partaking in at least two and a half hours of activity a week. A patient may gradually increase this to five hours a week if applicable (DASH, 2015). Once these changes have been made and the patient is giving full participation in their treatment, the DASH diet plan will be in full effect. Thus, beginning the journey to lower the patient’s blood pressure.
References
Anderson, J., Young, L., & Long, E. (2008, August). Health. Diet and Hypertension. p. 1-2.
Balch, H., Splitter, S., Flynn, P., & Kinsell, L. W. (1958, September). Western Journal of Medicine. THE RELATIONSHIP OF DIETARY FAT TO ATHEROSCLEROTIC DISEASE. p. 165-168.
Graudal, N. A., Hubeck-Graudal, T., & Jurgens, G. (2011, November 09). US National Library of Medicine. Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride.
Hall, J. E. (2003, March). Hypertension. The kidney, hypertension, and obesity.
National Heart, Lung, and Blood Institute. (2006, December). Your Guide to Lowering Your Blood Pressure with DASH. p. 1-6.
Treasure, J., & Ploth, D. (n.d.). Hypertension. Role of dietary potassium in the treatment of hypertension.