Focus on blood pressure

High blood pressure (hypertension) can threaten lives. It is often referred to as the silent killer because it rarely causes symptoms. High blood pressure increases the risk of heart disease, stroke and kidney failure and affects 1 in 4 adults. Approximately 31% men and 26% of women have high blood pressure.

What is blood pressure?

Blood pressure refers to how hard blood is pushing against the wall of arteries (blood vessels that take blood away from the heart). This pressure is necessary for blood to flow around the body. Think of water flowing through a garden hose and imagine you are turning the tap on and off.

How is blood pressure measured?

Blood pressure readings consist of two numbers, usually shown as one on top of the other and measured in mmHg (millimetres of mercury) such as 140/90mmHg. The first is the pressure when the heart contracts to pump blood (systolic). The second number is when the heart is relaxing and filling up with blood (diastolic).

What is normal blood pressure?

Normal readings for blood pressure should be below 140/90mmHg^[1]

Does blood pressure vary throughout the day?

Blood pressure naturally varies throughout the day depending on posture, activity, and stress. It can also be elevated or lowered because of illness or disease.

How often should blood pressure be checked?

All adults should consider having their blood pressure measured at their GP surgery every two years.  

Which foods can I eat to lower high blood pressure?

Your diet is a natural way of helping keep blood pressure within a healthy range. Following a plant-based diet containing vegetables, wholegrain cereals, pulses, and fruit helps to keep BP under control. Here are some foods that have been shown to help lower blood pressure.

1. Rolled oats

Eating 60g rolled oats per day can help to reduce blood pressure.

The fibre in oats produce bioactive products when they are digested in the gut. These work directly to lower blood pressure.

2. Beetroot

Beetroot contains a chemical called nitrate which gets converted into nitric oxide when digested. Nitric oxide directly lowers blood pressure.

Beetroot makes a very tasty soup and is delicious juiced. They can be baked in foil or simply boiled and served as a vegetable with a tahini and yogurt dressing and some chopped dill.

3. Foods containing vitamin C and potassium

Foods containing vitamin C and potassium help to lower blood pressure. Fruit and vegetables are a good source of potassium and vitamin C.

Potassium helps to counter the effects of salt in the diet which tends to raise BP.  Vitamin C acts as a mild diuretic removing excess fluid from the body which helps lower BP.

Which foods should I avoid to lower blood pressure?

1. Salt

High salt intakes are associated with high blood pressure. Most processed foods are high in salt. Adults should limit their salt intake to no more that 6g per day

2. Alcohol

Drinking alcohol raises blood pressure. One or more alcoholic drink a day is associated with an increase in blood pressure. Interestingly, when you first drink an alcoholic beverage, blood pressure goes down, only to rise later.

3. Caffeine

High intakes of caffeine can increase blood pressure. Some people are more sensitive to the effects of caffeine than others. Caffeine is contained in coffee, tea, cola and energy drinks.

4. Liquorice

Liquorice contains a substance called glycyrrhizic acid (GZA) which raises blood pressure. Most liquorice flavoured confectionery contains very little pure liquorice root so check food labels to avoid products containing it.

What else can I do to manage my blood pressure?

Taking regular exercise, stopping smoking, and keeping a healthy weight all help to reduce the risk of developing high blood pressure.

For further information on high blood pressure see the British Heart Foundation.