Hypertension is a serious health problem that can harden and thicken arteries. This can therefore lead to the development of health complications such as the heart and stroke. There are several risk factors for a person who develops high blood pressure, some of which are linked to poor food choices. It is known that eating a high amount of salt in food and regularly drinking large amounts of alcohol increases blood pressure.
To counteract these poor dietary choices, the NHS recommends reducing salt intake to less than 6 g per day by eating a low-fat, balanced diet, drinking less caffeine and reducing alcohol.
More specifically, studies have shown in particular foods and beverages to have blood pressure lowering qualities.
A study published in the British Journal of Nutrition in 2004 suggested that tea can help lower blood pressure.
But not just tea, green tea.
The researchers analyzed 25 randomized controlled trials, which represent the gold standard of scientific research, to explore the association between tea and hypertension.
They found tea in the short term does not seem to make a difference to blood pressure.
But in the long run, drinking tea has had a significant impact.
The research showed after 12 weeks of drinking tea, blood pressure was lowered by 2.6 mmHg systolic and 2.2 mmHg diastolic.
The systolic pressure is the highest number in a reading and measures the strength with which your heart pumps blood around your body.
Diastolic pressure is the lowest number in a reading and measures the resistance of blood flow in blood vessels.
Green tea has been found to have the most significant results. Black tea was the second best result.
While the change in blood pressure reading may not seem great, the researchers wrote that reducing systolic blood pressure by 2.6 mmHg "should reduce the risk of stroke by 8%, mortality due to the ; 5% coronary artery and all causes 4% mortality at the population level ".
The researchers in this study were unable to identify how many cups of green tea you should drink per day to lower blood pressure, but other studies have suggested that three or four cups of tea a day may be effective.
One food that has been found to have blood pressure lowering qualities is onion.
Its powerful anti-inflammatory properties can help reduce hypertension and quercetin, a highly concentrated flavonoid antioxidant in onions, can also be effective.
A study involving 70 overweight people with high blood pressure found a dose of 162mg a day of quercetin-rich onion extract, significantly reducing systolic blood pressure by 3-6 mmHg compared to a placebo.