Some people have low blood pressure and many people have normal blood pressure, but millions of people in the UK have high blood pressure, which increases the risk of heart disease and stroke.
Find out what changes you can make to your diet to help reduce your blood pressure.
Blood pressure is the force of blood pressing against the walls of the arteries as the heart pumps blood around the body.
The heart beats by contracting and relaxing. Every time the heart contracts, it forces blood around the body. This is a heartbeat. The heart rests briefly between each heartbeat.
The pressure of blood flowing through your arteries is higher when your heart contracts than when it relaxes. So when a doctor or nurse takes your blood pressure, they look at two different measurements.
Systolic pressure is the pressure when the heart contracts and forces blood around the body.
Diastolic pressure is the pressure when the heart is resting. This is lower than systolic pressure.
Blood pressure is measured in millimetres of mercury (mmHg).
When someone tells you what your blood pressure is, they will give one figure for your systolic pressure and another for your diastolic pressure. For example, if you have a systolic pressure of 130mmHg and a diastolic pressure of 70mmHg, they will usually say that your blood pressure is '130 over 70'.
Raising your blood pressure triples your risk of developing heart disease or having a stroke, whatever your age. Reducing your blood pressure reduces your risk of heart disease and stroke, even if your blood pressure is already within the normal range.
Evidence shows that cutting down on salt, especially as part of a healthy diet that includes plenty of fruit and vegetables, can reduce blood pressure
More than 130,000 people every year in England and Wales have their first stroke – about 10,000 of these people are under retirement age.
Stroke affects the blood vessels that supply blood to the brain. A stroke is caused by one of these blood vessels bursting or becoming blocked by a blood clot. When this happens, the part of the brain supplied by the blood vessel doesn't get enough oxygen and is damaged.
Stroke affects people in different ways, depending on what part of the brain is damaged. The part of the body linked with the damaged section of the brain is affected. Strokes often cause paralysis, usually on one side of the body.
High blood pressure can increase the risk of heart disease in a number of different ways.
It can damage the heart because the extra pressure means the heart has to work harder to pump blood around the body. This damage can lead to heart failure and increase the risk of having a heart attack.
High blood pressure also increases the risk of atherosclerosis, where fatty deposits are laid down inside the arteries. This makes the blood vessels narrower and stiffer, which can raise blood pressure further and increase the risk of having a heart attack.
There are a number of things that increase the risk of developing high blood pressure, including:
eating too much salt
being overweight
not being physically active
drinking too much alcohol
If one or both of your parents have high blood pressure, you are also more likely to develop it.
Evidence shows that cutting down on salt can reduce blood pressure, especially if this is part of a healthy diet including plenty of fruit and vegetables.
Drinking too much alcohol can raise blood pressure, so we should try not to drink more than 2 or 3 units a day for women and 3 or 4 units a day for men. A unit is half a pint of standard strength (3 to 5% ABV) beer, lager or cider, or a pub measure of spirit. A glass of wine is about 2 units and one alcopop is about 1.5 units.
Reducing your blood pressure reduces the risk of developing heart disease and stroke, even if your blood pressure is already within the normal range.
Some people have low blood pressure. But they still need to eat a healthy diet that is low in fat, sugar and salt, and high in fruit and veg.
Most people with high blood pressure don't have any symptoms. The only way to find out is to have your blood pressure measured.
Everyone's blood pressure goes up and down at different times of the day. Sometimes it can be higher when you're anxious or stressed. Usually your doctor or nurse will take your blood pressure several times before deciding if you have high blood pressure. Then your doctor may prescribe medication to lower your blood pressure.
There isn't a fixed threshold between normal and high blood pressure. But generally a pressure below 140/90mmHg would be considered normal.
Eating less salt can help reduce blood pressure. We can all take steps to cut down on salt by shopping wisely and being sparing with salt at home.
Lots of everyday foods are high in salt. In fact, 75% of the salt we eat is already in the food we buy.
Foods such as bacon, cheese and pickles are salty because of how they are made. Soy sauce, yeast extract and stock cubes are also high in salt.
Often foods such as breakfast cereal, baked beans, biscuits, soup, pizza and ready meals are high in salt. The amount of salt they contain varies from one brand or recipe to another. So compare different products by checking the labels.
If you check labels to find out which foods are high in salt you will be able to choose the healthier option and start helping to reduce your blood pressure.
Look at the figure for salt per 100g.
High is more than 1.5g salt per 100g (or 0.6g sodium) Low is 0.3g salt or less per 100g (or 0.1g sodium)
If the amount of salt per 100g is in between these figures, then that is a medium level of salt.
Remember that the amount you eat of a particular food affects how much salt you will get from it.
Try to avoid eating lots of foods that are high in salt. If you eat lots of these foods, it can be very easy to have more than your daily maximum. This is why it's important to choose foods that are lower in salt, when you can.
Try not to add salt automatically when you're cooking or about to eat. Often people use salt out of habit.
There are lots of other ways to add flavour to food, including using herbs, lemon juice, garlic and chilli.
If you or your family are used to eating foods that are high in salt, or adding lots of salt to your food, you could miss it at first.
But our taste buds get used to eating less salt in a few weeks, so start gradually and you will soon be enjoying your food with hardly any salt at all.
