One in three adults in the UK have high blood pressure (BP) and, according to the British Heart Foundation, around seven million people have it without knowing they do.
The good news is a few simple dietary tweaks can help to keep BP in check. Cut back on sodium, found in table salt and processed foods such as breakfast cereals, tinned soups, takeaways and ready meals; keep an eye on the booze; boost potassium, found in fruit, vegetables, nuts, wholegrains, meat, poultry, fish and milk; and eat an overall healthy diet to benefit from the vital synergy of nutrients all working together.
Eat your greens for healthier arteries
Do your BP a big favour and pile your plate high with green leafy veg and herbs – think cabbage, celery, chard, dill, kale, leeks, lettuce, rocket, parsley and spinach. The reason? They are exceptionally rich in nitrates, compounds derived from nitrogen, which help to widen arteries and keep them elastic. In a recent review of 34 studies published in Nutrition Reviews, researchers concluded that a higher intake of nitrates significantly reduced both systolic and diastolic BP (see Need to Know, right), improved elasticity of the lining of the arteries (the endothelium) and reduced arterial stiffness. Stiff, narrowed arteries are a key reason that BP rises.
How beetroot juice helps you beat BP
According to recent research, beetroot juice lowers BP overall and in particular pushes down that all-important systolic BP by 5mmHg. This is on a par with taking an anti-hypertensive drug or following the Dietary Approaches to Stop Hypertension (DASH) diet (see below), which is linked to a considerable lowering of stroke risk. And these effects are greater in older people and those who have existing health problems. But, obviously, don’t stop taking medication without talking to your GP.
The secret? Beetroot is rich in nitrates as well as polyphenol plant chemicals that help to enhance the effects of nitrates. It also has other BP-lowering nutrients including potassium, calcium and magnesium. Buy or make beetroot juice, roast, bake or stir-fry it, or make borscht.
Eat nuts to lower blood pressure
Nuts have long been associated with BP-lowering properties. Pistachios are especially powerful in lowering systolic and diastolic BP, while mixed nuts may help to lower the latter. A trial of 211 people in last June’s Australian HealthTrack study found that 30g of walnuts a day as part of a tailored diet enhanced the effects of weight loss and was linked to a significant drop in systolic BP. Walnuts lowered the sodium/potassium ratio in the blood, vital for healthy BP.
How ‘good’ bacteria helps blood pressure
Growing research points to the potential benefits of probiotics, ‘good’ bacteria found in fermented dairy – yogurt, kefir, buttermilk, etc – on lowering BP. Why? Well, it seems that small protein fragments called peptides found in fermented milk products act like ACE-inhibitors, a medication prescribed to keep BP in check. These block a chemical called angiotensin-converting enzyme, so causing blood vessels to relax and reducing the amount of water re-absorbed by the kidneys. Probiotics also trigger formation of compounds called short-chain fatty acids in the gut, which have a BP-lowering effect.
Diets that may help lower blood pressure
Two specific dietary patterns that can help are the DASH diet and the Mediterranean diet. Low in red meat, added sugar and fat, the DASH diet includes plenty of fruit and veg, lean proteins from foods such as chicken and fish and pulses, and limits salt to no more than 6g – a teaspoon – a day.
Salt increases the sodium/ potassium ratio, reducing the kidneys’ ability to remove water, and causing BP to rise due to extra fluid in the bloodstream, which puts a strain on the blood vessels.
The Mediterranean diet is similar with olive oil as the main source of fat.
Drink less booze
Alcohol can harm BP, so stick to no more than 14 units a week. Easing up on the booze can bring a fall in BP within days.
A beginner's guide to blood pressure
What is blood pressure?
The force exerted against the artery walls as your heart pumps blood around the body. The top number, the systolic BP, is the highest level of BP when your heart beats. The bottom number, the diastolic BP, is the lowest level of BP when your heart relaxes between beats. Systolic BP is considered the more important reading in terms of increasing the risk of stroke and heart attack.
What are the dangers of high BP?
High BP (hypertension) places extra strain on the heart and blood vessels, raising the risk of heart attack or stroke. Hypertension can also cause heart and kidney disease and is linked with vascular dementia.
What should my BP be?
Ideally, 120/80 or less. The higher your BP, the greater your risk of health problems, even if it is not officially ‘high’ (ie 140/80). So a BP reading of 135/85 carries double the risk of heart attack or stroke as a reading of 115/75.
Saga Health Insurance may be able to provide you with cover even if you already have high blood pressure (hypertension), subject to some simple health questions and an additional premium. Find out more.