High blood pressure can be a ‘silent killer’ because there are usually no symptoms. The only way to find out whether your blood pressure is high is to get it checked. The top number (systolic) measures the pressure of the blood when your heart pumps it out around your body. The bottom number (diastolic) measures the pressure when your heart relaxes and fills up with blood, ready for the next pump. Think of your arteries as a garden hose with your heart as the tap. If you turn the tap on high the water pumps out at high pressure. If you turn the tap down the pressure drops. Sometimes we need to get blood out to our muscles fast: jumping out of the way of a speeding car is one good reason! In this case high blood pressure may be a life saver. But if your blood pressure is constantly high, you increase your risk of a stroke, heart attack, heart failure and kidney disease. Here are the first three changes you can make to help reduce high blood pressure. More tomorrow…
1. Eat less salt
Most of us eat more salt, or to be exact, sodium, than we need. The NHMRC recommends no more than 1600mg sodium a day for healthy blood pressure. In New Zealand we eat at least double that amount. That’s almost 2 teaspoons of salt a day. Even if you don’t sprinkle salt on your food, around three-quarters of the salt we eat comes from processed foods such as bread, sauces, soups, processed meat, some breakfast cereals, cheese and salty snacks.
High sodium foods don’t always taste salty. A plate of cornflakes or rice bubbles has as much sodium as a small bag of potato crisps. And a slice of bread can have the same amount of sodium as the teaspoon of Vegemite you spread on it!
If you have to cut back on salt, don’t despair. For the first three or four weeks food will taste bland but your taste-buds do adjust. Then you will find your old food far too salty.
Cutting back on salt will likely reduce your blood pressure. This is especially so for older people and those who already have high blood pressure, diabetes, kidney disease or are overweight. However some people are salt insensitive. This means that the amount of salt they eat has no effect on their blood pressure. What else can these people do?
2. Reduce weight
If you are overweight, losing weight is one of the best ways to drop your blood pressure. If you are already on medication, losing weight often helps it to work better and you may even need a lower dose. Studies have found that people who lost 3-9% of their weight reduced their systolic (top number) and diastolic (bottom number) pressure by an average of 3 points more than people who did not lose weight (see BMJ Best treatments)
3. Be active
Thirty minutes (not necessarily all at once) a day of moderate intensity exercise such as walking, cycling, dancing, gardening or swimming helps drop both your blood pressure and your weight. In fact it can reduce high blood pressure as much as some drugs. People who are physically active have a quarter to half the risk of high blood pressure. Building strong muscles is also important but skip the heavy weights if your blood pressure is already high. All that groaning and straining will likely send it shooting higher!
Part 2 here …