High blood pressure or hypertension is on the increase. Around 16 million people (1 in 3) in the UK and around 1 billion people worldwide live with hypertension, many of whom are unaware of the condition. High blood pressure is commonly referred to as the ‘silent killer’ as there are no obvious early symptoms until it has done damage to the heart and arteries.
Make no mistake. Hypertension is a serious health concern and when left unnoticed or untreated can lead to a higher risk of coronary heart disease (CHD), stroke or even kidney failure.
The good news though is that once diagnosed, high blood pressure is easily treated with medication or in some cases can be managed by getting regular exercise and by making simple dietary and lifestyle changes. One such dietary solution that is commonly prescribed by doctors is the DASH diet.
What is the DASH Diet?
DASH stands for Dietary Approaches to Stop Hypertension and was developed by health researchers who noticed that vegans or vegetarians were less likely to have high blood pressure due to their plant-based diets. https://www.ncbi.nlm.nih.gov/pubmed/10410299
The diet itself is easy to follow and encourages you to:-
So basically, reduce your red meat intake, bad fats and added sugars.
Another important criteria is that you limit your salt intake to no more than 2,300 mg or 1 teaspoon per day. Too much salt has always been associated with high blood pressure and the DASH diet enforces this fact.
What is a High Blood Pressure?
Blood pressure is the measure of the force placed on the walls of the arteries and organs of the body when blood is passed through them.
When a medical practitioner takes your blood pressure, they will be checking two figures. These are:-
The figures are usually displayed as two numbers, one on top of the other, systolic on top and diastolic on the bottom, for example 130 over 85 mmHg.
Doctors will usually like to see a reading lower than 140/90 mmHg. If your blood pressure is 140/90 mmHg or greater, you are considered to be hypertensive or have high blood pressure.
How Effective Is The DASH Diet in Lowering Blood Pressure?
In a number of controlled studies, people who were placed on the DASH diet reduced their blood pressure significantly, some achieving this in only 2-4 weeks.
In one such study by the John Hopkins University in Baltimore U.S.A, 412 adults ranging from the ages of 23 to 76 were tested. Each had a systolic reading of between 120-159 mmHg and a diastolic reading of between 80-95 mmHg. None of the participants were on any antihypertensive medication and none of them had received any prior diagnosis.
Participants were then sorted into groups based on their systolic blood pressure reading and placed on either a DASH diet or control diet for 12 weeks. They were also fed between 50-150 mmol of sodium in random order over a four week period.
After just four weeks of implementing the DASH diet, researchers found that participants with the baseline systolic readings of 150 mmHg or above had an average reduction of 11 mmHg, compared to those who’s systolic baseline figure was 130 mmHg or less, who saw a drop of around 4 mmHg.
What was most startling was that when the DASH diet was combined with a low salt/sodium diet the reductions were even greater.
At the end of the 12 weeks, the study found that participants with a baseline systolic blood pressure reading of 150 mmHg or greater prior to the study, reduced their systolic reading by around 21 mmHg when combining the DASH diet with the low salt/sodium diet.
You can read more about the study here.
Other Benefits Of The DASH Diet
The DASH diet is not only proven in reducing blood pressure. As you will be eating a more balanced, nutritious and all round healthier diet, you will experience many other health benefits such as a reduced risk of osteoporosis, cancer, heart disease, stroke , metabolic syndrome and diabetes.
A study by the British Medical Journal found that the DASH diet was also associated with a lower risk of gout due to its ability to reduce uric acid levels in the body, which is the cause of gout, arthritis and other inflammatory conditions - https://www.bmj.com/content/357/bmj.j1794
You Will Also Lose Weight
If you are overweight and have high blood pressure, you will often be advised by your doctor to reduce your calorie intake and shed the pounds.
If you follow the DASH diet and reduce your intake of sugary foods and saturated fats you should naturally start to lose weight, but don’t forget to exercise.
Getting more exercise is one of the easiest and fastest ways of reducing high blood pressure. As a guide, you should be getting around 30 minutes of physical exercise per day. This can be brisk walking, jogging, going to the gym, swimming or even housework or gardening.
Whatever you do, make sure you are getting that heart pumping and that you are spending less time sitting down and more time on your feet moving around!
Instead of getting off the bus at your usual stop, get off two stops early and walk the rest of the journey. Instead of taking the elevator, take the stairs.
We can all make small changes each day to help increase our heart rate, burn calories and generally improve our fitness levels. It just takes the will to do it!
Further information on recommended daily exercise can be found via the UK NHS website at https://www.nhs.uk/live-well/exercise/
Starting the DASH Diet
To start the DASH diet, you will need to start eating foods from the different food groups. How much you eat will depend on the number of calories you should be consuming.
Another important aspect to the DASH diet is to reduce your sodium levels. Ideally, you will need to reduce this to around 2,300 mg or 1 teaspoon per day. This amount includes the amount of sodium that you have in any meals that you cook as well as any that you add at the table.
There is also a lower sodium/salt version that requires that you consume no more than 1,500 mg or 3/4 of a teaspoon of salt per day. Start with the 2,300 mg version and reduce your salt intake slowly until you reach the 1,500 mg version of the diet.
Although there are no specific guidelines on exactly which foods you should be eating on the DASH diet, it does instead focus on the number of servings that you should be eating from the different food groups. For example:-
You should also reduce your intake of caffeine and consume alcoholic beverages sparingly. Attempt to stick to national government guidelines as much as possible.
For further information on the DASH diet including recipes, eating plans and research, please see the following resources or search ‘dash diet’ on Google.
https://www.nhlbi.nih.gov/files/docs/public/heart/new_dash.pdf
https://www.healthline.com/nutrition/dash-diet
https://www.webmd.com/hypertension-high-blood-pressure/guide/dash-diet#1
https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/dash-diet/
https://www.sciencedirect.com/science/article/pii/S0735109717410989
Disclaimer: This article and the content within it has been created for informational purposes only and is not intended to replace professional medical advice, treatment or diagnosis. We would always encourage you to speak with your doctor or health practitioner before undertaking any new dietary program.
Updated: November 17, 2023 CET