High blood pressure
Having high blood pressure (also known as hypertension) can increase your risk of developing conditions such as heart disease and stroke. High blood pressure rarely has symptoms, so it's important to monitor it.
On this page, we will explore hypertension in more detail and discuss how dietary changes can help support lowering blood pressure.
Understanding blood pressure
When we talk about blood pressure, we are talking about the measure of force your heart uses to pump blood around your body. This measurement tells you whether your blood pressure is low, normal or high. It is estimated that around 30% of people in England have high blood pressure, but many don't realise they have it.
High blood pressure can be a sign of unhealthy habits, including smoking, drinking too much alcohol, not getting enough exercise, or being overweight. Without treatment, high blood pressure can lead to developing long-term, serious health conditions such as coronary heart disease, kidney disease, heart attack, or stroke.
Low blood pressure is much less common. It can be caused by other underlying conditions, such as dehydration, heart failure, or pregnancy. It can also be a side effect of some medications.
Generally, the lower your blood pressure, the lower your risk of experiencing heart attack or failure, stroke, vascular dementia, or kidney disease.
Measuring your blood pressure
To find out your blood pressure you will need two measurements to be taken within a single heartbeat. One is the systolic pressure - the level of pressure when your heart is pumping blood. The other is the diastolic pressure - the level of pressure when your heart is resting before it pumps again.
The measurement for blood pressure is in millimetres of mercury (mmHg) and the readings are given in the form of two numbers. The first number is your systolic reading and the second number is your diastolic pressure. So, if your systolic reading is 120mmHg and your diastolic reading is 80mmHg, your blood pressure would be 120 over 80. Doctors typically write this as 120/80.
To measure your blood pressure, a manual or automatic device can be used. Your doctor will place a cuff around the top of your arm and pump it full of air to temporarily restrict blood flow. The air is then slowly released while your pulse is checked. Hearing the way your pulse beats once the air has been released allows a measurement to be taken.
For an accurate reading, you should be seated with your legs uncrossed and your back supported. If your reading is continually higher than average, you may be diagnosed with hypertension.
Symptoms of high blood pressure
High blood pressure is often referred to as the 'silent killer' because it rarely has any noticeable symptoms. If high blood pressure is left untreated, it can lead to serious health conditions.
In extreme cases and when blood pressure is very high, there can be noticeable symptoms, including:
- blurred/double vision
- constant headaches
- shortness of breath
If you are experiencing any of these symptoms, you should see your doctor as soon as possible.
As there are rarely symptoms you can see or feel, it is recommended that you have your blood pressure monitored regularly. Adults are advised to get it checked at least once every five years.
If you are at risk of high blood pressure, you may need closer monitoring. You may also be advised to take preventative measures to reduce your risk of hypertension.
Who is at risk of developing high blood pressure?
The risk of having high blood pressure increases as you get older, especially after the age of 65. As well as age, there are other risk factors - these include:
- being overweight
- not exercising enough
- not eating a balanced diet (too much salt or not enough fruit and veg)
- drinking too much alcohol or caffeine
- being a smoker
- having a family history of high blood pressure
- not getting enough sleep or having poor quality, disturbed sleep
- are of black African or black Caribbean descent
If you fall into these categories, making changes to your lifestyle and diet can help you manage your blood pressure. You should also have your blood pressure checked more regularly, ideally once a year.
Preventing high blood pressure
To help prevent hypertension, there are many lifestyle changes you can make. It’s recommended that you eat healthily, maintain a healthy weight, exercise regularly, drink in moderation (or stop drinking alcohol), and stop smoking. You should drink no more than 14 units of alcohol a week, spread over at least three days.
Reducing the amount of salt you consume (ideally 6g or less - the equivalent of a teaspoon) and increasing the number of fruits and vegetables (at least five portions a day) that you eat is also recommended. Eating a healthier, more balanced diet can be a big help. Having plenty of fibre (wholegrain rice, bread, and pasta) can also help to lower blood pressure.
High blood pressure and pregnancy
For pregnant women, having blood pressure checked regularly is essential - even if it isn't high to begin with. Some women can develop pregnancy-induced hypertension, which can lead to a condition called pre-eclampsia. This can compromise the placenta - the organ that links the mother's and baby's blood supply.
Taking gentle exercise and eating a diet with foods to lower blood pressure can help reduce your risk.
What is the main cause of hypertension and high blood pressure?
In around 90-95% of cases, the exact cause of high blood pressure is unknown. However, the risk factors described above are known to increase your chance of developing the condition. In the remaining 5-10% of cases, the cause of high blood pressure can be linked to a condition or specific cause. This is known as secondary hypertension.
Common causes of secondary hypertension include:
- hormonal conditions
- tissue-related conditions (like lupus)
- renal disorders (chronic kidney disease, polycystic kidney disease, renal cell carcinoma, diabetic nephropathy)
- narrowing of arteries supplying the kidneys
- oral contraceptive pill
- certain painkillers
- recreational and some prescription drugs
How is hypertension related to nutrition?
What we eat can increase our likelihood of having high blood pressure. For example, the more salt you eat (above the recommended 6g or one teaspoon per day maximum), the higher your blood pressure is. Ensuring you eat a low-fat diet filled with fibre, fruit and vegetables, as well as cutting back on caffeine and alcohol can help lower your blood pressure. Having more potassium, polyunsaturated fatty acids, protein and vitamin D in your diet can also help.
It’s important to remember to make other healthy lifestyle changes alongside altering your diet. Regular exercise is recommended.
How to treat high blood pressure
Many people find that diet and lifestyle changes can treat high blood pressure, though some GPs may also recommend medication.
Sticking to a healthy lifestyle has many benefits, including lowering blood pressure. Try the following to maintain normal blood pressure:
Eat a balanced diet
What you eat and drink can have a big impact on your blood pressure. Understanding which foods can help to manage hypertension, reducing your salt consumption and keeping to a healthy weight are all important. We will go into this in more detail further down the page.
Although smoking doesn't directly cause hypertension, it puts you at a greater risk of heart attack and stroke. This means if you smoke and have high blood pressure, you will be at a significantly higher risk.
Get enough exercise
Taking enough exercise will help to keep your blood vessels and heart in good condition, lowering your chances of high blood pressure. On top of this, regular exercise can help you lose any excess weight - another risk factor for hypertension. Adults are recommended to get 150 minutes of exercise every week. This exercise should make you feel warm and slightly out of breath.
Reduce your stress
Feeling stressed all the time (known as chronic stress) can raise your blood pressure significantly. Try to establish what it is in your life that is causing your stress and think of ways you could look to reduce it. Understand your stress triggers and learn relaxation techniques to help you cope when they occur. Ensure you make time every day to relax - this could be five minutes of meditation, taking the dog for a walk or even enjoying a long bath.
Your doctor will inform you if you need to take medication to help manage your blood pressure. Different medications may be used to help relax your blood vessels, block calcium from entering your heart and blood vessels muscle cells, flush out excess water and salt, or make your heart beat slower and less forcefully. Medication should always be discussed with your GP before starting or stopping.
High blood pressure and weight
If you are overweight, your heart has to work harder to pump blood around the body and this can raise blood pressure. If you do need to lose weight, it's useful to remember that losing even a few pounds will make a difference.
The best way to lose excess weight is to follow a balanced, calorie-controlled diet and increase your physical activity. Many find it helpful to get professional support from a nutritionist to help them lose weight - you can find out more on our weight-loss page.
What is a high blood pressure diet?
A diet that is low in fat and high in fibre and fruit and vegetables can help to lower blood pressure. Fruit and vegetables are full of vitamins and minerals our bodies need to stay fit and healthy. It is recommended that you get at least five portions of fruit and vegetables a day.
Changing your eating habits can be difficult - even when we know the health benefits. This is why many people seek support from a suitably qualified nutrition professional. These professionals will not only create a diet plan for you to follow, they will also provide support to help you change your habits.
One important aspect of reducing your blood pressure is limiting certain foods and drinks. This is because some foods can greatly increase your risk of becoming hypertensive.
Foods to limit
The following foods should be limited when addressing high blood pressure:
The more salt you consume, the more likely it is that your blood pressure will rise. Salt has such a significant impact, that many people find cutting their intake is all that's needed to lower their blood pressure.
Experts recommend you eat no more than 6g of salt a day. Helpful ways to do this can include:
- Avoid adding salt to meals. Instead, use herbs and spices to enhance flavour.
- Read food labels. Find out how much salt is in your food and be mindful of going over your limit.
- Avoid processed foods. Most processed foods like sauces, soups and ready meals are high in salt.
Having too much cholesterol in your blood can increase your risk of heart disease and stroke. If you have high blood pressure, it is very important to keep cholesterol levels low. Saturated fats raise your cholesterol, so be sure to limit these in your diet.
Saturated fats are typically found in fatty cuts of meat, cream, cheeses, cakes, and biscuits. Reducing your intake of these and swapping them for healthier alternatives will help to lower cholesterol and improve your general health.
In contrast to this, monounsaturated and polyunsaturated fats actually help to lower cholesterol. These types of fats can be found in olive oil, avocados, vegetable oils, oily fish and nuts and seeds. Include these in your diet, but remember as they are still technically fats, they can cause weight gain if you overindulge. Enjoy in moderation.
If you regularly drink more than the recommended amount of alcohol, over time your blood pressure will rise. On top of this, alcohol can affect blood pressure medication, making it less effective. Staying within the recommended limits is the best way to help manage your blood pressure. Current guidelines recommend that both men and women should drink no more than 14 units of alcohol per week - this equates to no more than one to two units a day.
It is thought that drinking more than four cups of coffee a day can increase blood pressure. While more research is required to understand the effects caffeine has on blood pressure, you may benefit from limiting the amount you consume. Try and switch to herbal teas instead of coffee and flavoured sparking water instead of fizzy or energy drinks.
Foods to lower blood pressure
Research suggests that as well as reducing the food groups described above, you should look to include foods that contain the following key minerals:
- Calcium - This helps blood vessels tighten and relax when they need to.
- Magnesium - This helps to regulate many body systems, including blood pressure.
- Potassium - This is important for muscle function and helps to relax the walls of blood vessels.
These three minerals, in particular, are believed to help reduce hypertension. Try to include the following foods to lower blood pressure:
- Spinach - high in fibre and a good source of potassium and magnesium.
- Sunflower seeds - these make a great snack and contain magnesium (enjoy unsalted varieties).
- Beans - great for overall heart health, beans are full of fibre and contain potassium and magnesium.
- Banana - an ideal on-the-go snack, bananas are a good source of potassium.
For more advice on foods to lower blood pressure, you are advised to seek a nutrition professional.
Working with a nutritionist for hypertension and to lower blood pressure
A nutritionist or dietitian can be a huge help in supporting you to get your blood pressure under control and lowering your risk of developing further issues. A nutritional professional can help you through:
- Assessing your current diet and lifestyle habits, identifying areas where you may be having more salt, saturated fats, or caffeine than you may realise.
- Helping you to include more fruit, vegetables, ‘healthy fats’, and vital nutrients and minerals in your diet.
- Creating a tailored diet plan (a high blood pressure diet) to suit your individual needs and circumstances.
- Helping you to learn more about foods, nutrients, minerals, and healthy, easy recipes to support lifestyle changes.
- Sharing foods to include that can help lower blood pressure and foods to be mindful of.
Ready to work with a nutritionist? Enter your details in the search bar below or use our advanced search to find a qualified, experienced nutritional professional online or in-person near you.
All content displayed on Nutritionist Resource is provided for general information purposes only, and should not be treated as a substitute for advice given by your GP or any other healthcare professional.