Excerpted and adapted from "What's New with Your Blood Pressure?", Stroke Connection Magazine January/February 2005 (Science updated July 2008)High blood pressure (HBP) is the leading modifiable risk factor in ischemic and hemorrhagic strokes. And in more than three-fourths of first strokes, patients have blood pressure higher than 140/90.
The latest guidelines from the National Heart, Lung, and Blood Institute (NHLBI) say blood pressure numbers between 120-139 systolic or 80-89 diastolic indicate “prehypertension.” This means that 100 million Americans whose blood pressure had been considered normal now have cause to watch their pressure more closely.
The guidelines say that prehypertension is best treated with:
- Weight loss
- Restriction to no more than 1,500 mg sodium per day
- A diet rich in fruits, vegetables and low-fat dairy products and reduced saturated fat and total fat
- Moderate use of alcohol (no more than two drinks a day for men or one drink a day for women. A drink is one 12 oz. beer, 4 oz. of wine, 1.5 oz. of 80-proof spirits, or 1 oz. of 100-proof spirits.)
Several things may affect blood pressure, including:
- Retaining too much fluid in the body can increase pressure in blood vessels.
- Retaining fluid can be caused by several factors, including a high-salt diet.
- Limiting salt intake is important to treating high blood pressure.
- Diuretic medications can also help reduce extra fluid.
Constriction of blood vessels also increases blood pressure. Substances called “vasopressors” cause blood vessels to constrict (squeeze and narrow the path for blood flow). This makes blood move through them at higher pressure. Watch an animation of high blood pressure.
Salt and High Blood Pressure
Salt intake affects blood pressure levels in about 60 percent of people with high blood pressure. Salt (sodium chloride) is 40 percent sodium by weight. Sodium is a mineral that is essential for the body, but you must have a certain balance of sodium and water in your body fluids and tissues at all times. Too much sodium makes the body hold on to fluid. The increased fluid volume means the heart has to pump harder to handle the additional output, and blood pressure rises as a result. Your kidneys are responsible for regulating salt and water levels in your body, but high blood pressure makes it harder for the kidneys to function properly. High blood pressure is very damaging to the heart, the vascular system and the organs it supplies. High blood pressure is also a risk factor for stroke.
People should aim to consume less than 1,500 mg of sodium a day. Some people with mild high blood pressure can lower their blood pressure by reducing sodium in their diet. Medicines called diuretics or “water pills”, prescribed by a doctor rid the body of excess fluids and sodium and help reduce blood pressure.
Learn how to shake the salt habit.
Important Hypertension Tips
It is Important to:
- Know your numbers and your blood pressure goal.
- Monitor your blood pressure regularly.
- Record your blood pressure for your doctor and pharmacist.
- Eat and exercise responsibly.
- Ask your doctor for a comprehensive plan (diet, exercise and medicine, if necessary) and follow it.
- Take your medicines as directed. Ask questions about your medicines.
- Keep a list of over-the-counter medications and prescriptions you're taking.
Discuss any problems you’re having and work with your doctor to find the right dosage and combination of medicines – and lifestyle changes – that keep your hypertension in check and your stroke risk reduced.
Learn even more about high blood pressure at our HBP website.