Everything you need to know about the DASH diet

High blood pressure is one of the most common health issues in the modern world, affecting more than a billion people worldwide, with that number predicted to rise (1).

In England alone, it affects more than one in four adults and is the third biggest risk factor for premature death and disability after smoking and poor diet.

The good news is that, with a few simple changes to your diet and lifestyle, blood pressure can be reduced significantly.

What is blood pressure?

In its simplest form, blood pressure is the measure of the force put on your vessels and organs as your blood passes through them. It is measured in two forms:

• Systolic pressure – the pressure in your blood vessels when your heart beats.
• Diastolic pressure – the pressure in your blood vessels in between heartbeats.

When the pressure at which your blood travels around your body increases, it starts to damage artery walls in the form of small tears. As blood travels through the artery, bad cholesterol attaches itself to the tears and over timebuilds up making the artery narrow and harder for blood to pass through.

The restriction of blood can cause the heart to work harder and can lead to an enlarged left ventricle, which is the part that pumps the blood to the rest of the body. This can also put you at a high risk of having a heart attack, heart failure and sudden cardiac death.

Although it is not exactly clear what causes high blood pressure, several things can increase your risk.

Six risk factors for high blood pressure:

1. Age – the risk of developing high blood pressure increases as you get older
2. A high amount of salt in your food
3. Lack of exercise
4. Being overweight
5. Smoking
6. Regularly drinking large amounts of alcohol

Given that diet is thought to play a major role in the development of high blood pressure, researchers funded by NIH’s National Heart, Lung and Blood Institute (NHLBI) engineered a specific diet called the DASH diet to help combat it and reduce the risk of conditions such as heart disease, kidney failure and stroke.

What is the DASH diet?

Dietary Approaches to Stop Hypertension (DASH), is a diet recommended for people wanting to prevent or treat hypertension – also known as high blood pressure.

The DASH diet concentrates on fruits, vegetables, whole grains and lean meats.

Scientists formed the diet after observing that those who follow a plant-based diet, such as vegans and vegetarians, wereless likely to have high blood pressure (2). From these findings they developed a diet emphasising fruit and vegetables and reducing meat and processed food.

The DASH diet consists mainly of:

• Fruits
• Vegetables
• Lean proteins sources such as chicken, fish and beans

The diet also calls for reducing consumption of red meat, salt (no more than 1 teaspoon or 2,300mg per day), added sugars and fat.

Three benefits of the DASH diet

Although the DASH diet was developed mainly to reduce blood pressure, it has many beneficial effects beyond that. We look at three top benefits of the DASH diet. 

1. Lowers blood pressure

People with a blood pressure reading of 120/80 are considered to have normal blood pressure. Whereas, a reading of over 140/90 is deemed as high.

Studies have shown that when salt intake was lowered in people who have high blood pressure, systolic pressure was reduced by an average of 12 mmHg and diastolic pressure by 2 mmHg (3).

However, it is important to bear in mind that a decrease in blood pressure does not always decrease the risk of heart disease.

2. May aid weight loss

If you have high blood pressure you may have been advised to lose weight as research has found that the more you weigh, the higher your blood pressure is likely to be (4).

Given that the DASH diet lowers the intake of high-fat and sugary foods, people may find that they are automatically consuming less calories, leading to weight loss.

3. Decreases cancer risk

Due to the high content of fibre, nutrients, vitamins, minerals and antioxidants the foods in the DASH diet have, a recent review indicated that people following the diet had a lower risk of some cancers, including colorectal and breast cancer (5).

Top tips for starting the DASH diet

One of the key elements of this diet is reducing salt intake. However, this can be difficult as our palate’s become accustomed to the salty flavours in food, so removing it may make food taste quite bland. It also doesn’t help that salt is added to so many foods that we eat.

Here are a few tips to help cut down on salt:

• Use plenty of herbs and spices in cooking
• A squeeze of lemon or lime onto food can give a similar effect to salt
• Read the food labels to check for salt levels
• When possible try to make sauces and dips from scratch as these can contain a lot of salt

If you are interested in or have already started followingthe DASH diet, why not use our Health and Lifestyle Blood Test to see how your new lifestyle is affecting your health? With tests for liver and kidney function, heart healthand key vitamins,this is the perfect check to assess your current state of health.

References

1. Public Heath England (2015). Health matters: combating high blood pressure. [online] GOV.UK. Available at: https://www.gov.uk/government/publications/health-matters-combating-high-blood-pressure/health-matters-combating-high-blood-pressure.

2. Ha, S. (2014). Dietary Salt Intake and Hypertension. Electrolytes & Blood Pressure, 12(1), p.7.

3. Onvani, S., Haghighatdoost, F. and Azadbakht, L. (2015). Dietary approach to stop hypertension (DASH): diet components may be related to lower prevalence of different kinds of cancer: A review on the related documents. Journal of Research in Medical Sciences, 20(7), p.707.

4. Sacks, F., Moore, T., Appel, L., Obarzanek, E., Cutler, J., Vollmer, W., Vogt, T., Karanja, N., Svetkey, L., Lin, P., Bray, G. and Windhauser, M. (1999). A dietary approach to prevent hypertension: A review of the dietary approaches to stop hypertension (DASH) study. Clinical Cardiology, 22(S3), pp.6-10.

5. Staessen, J., Amery, A. and Fagard, R. (1988). The relationship between body weight and blood pressure. 2(2), pp.207-214.