What’s the right diet to help with high blood pressure?

Research shows that a couple of simple health changes could help lower your high blood pressure.

Right now, one in three Australian adults are living with high blood pressure – that’s more than six million people.

High blood pressure, also known as hypertension, is a major risk factor for heart disease. But according to a survey by the Heart Foundation, the vast majority of Aussies are unaware of the risks it poses. In fact, just 1% of us consider lowering, or even monitoring, our blood pressure. But recent research developments show that lifestyle changes, including the DASH diet, can make a big difference.

So what should we be doing, and why is it so important?

What is high blood pressure?

The systolic number (top or first number in a reading) is a measure of the blood pressure at its peak when the heart muscle contracts and pumps blood. The diastolic figure (bottom number) is measured when the heart relaxes and refills with blood.

Normal blood pressure is a reading between 90/60mmHg and 120/80mmHg. Anything from 120/80mmHg up to 139/89mmHg is considered ‘normal to high’ and over 140/90mmHg is considered ‘high’.

When your blood pressure is high, your heart and arteries are working really hard. Plaque can build up faster on the artery walls (atherosclerosis), limiting blood flow to your heart muscles – which can lead to a heart attack. The arteries in your brain can also be weakened, increasing your risk of a stroke.

Arteries in other parts of your body, including your eyes, kidneys and legs, can be impacted as well. Ongoing high blood pressure is known as hypertension.

Worldwide, the number of people with high blood pressure has doubled in the past 40 years. That’s a serious health concern, as high blood pressure is linked to conditions like heart disease, kidney failure and stroke.

What causes high blood pressure?

For most adults, there's no obvious cause of high blood pressure. Hypertension commonly develops bit by bit, over many years. Here are some of the main risk factors.

• Age – the risk of high blood pressure increases as you age.
• Family history – high blood pressure often runs in families.
• Being overweight – your blood pressure rises as your weight increases, because the increased blood flow puts pressure on your artery walls.
• Lack of exercise – being active helps keep your heart and blood vessels in good shape, which means they don’t have to work as hard to get blood around your body.
• Smoking – it causes your arteries to narrow, forcing your heart to work harder.
• High salt consumption – too much salt (sodium) in your diet can cause your body to retain fluid, which increases blood pressure.
• Lack of potassium – potassium helps regulate sodium levels. If you don't get enough potassium in your diet, sodium can build up in your blood, which can lead to increased blood pressure.
• Alcohol – drinking more than recommended amounts can raise blood pressure to unhealthy levels.
• Stress – high levels of stress can lead to a temporary increase in blood pressure.
• Chronic conditions – certain chronic conditions also may increase your risk of high blood pressure, including kidney disease, diabetes and sleep apnoea.

If you have a heart-related condition or diabetes, it’s never too late to start making positive changes. The COACH Program is a 4 to 6 month phone-coaching support program provided at no extra cost for eligible members* that can help improve your heart health.

How can you lower blood pressure?

The first thing to do is to be informed. That means having your blood pressure checked regularly by your GP or pharmacist.

“High blood pressure is known as a silent killer,” says Heart Foundation healthcare programs manager Natalie Raffoul.

“There are often no obvious signs or symptoms, yet it puts you at higher risk of a heart attack or stroke. The only way to find out if you need to do something about your blood pressure is to have it checked regularly.

“If you’re 18 or over, the Heart Foundation recommends you get your blood pressure checked at least every two years. If you are 45 and over, you should get your blood pressure checked as part of a regular, comprehensive heart health check,” says Natalie.

The next step is to make lifestyle changes that are proven to help lower your blood pressure.

“The good news is high blood pressure can be controlled through lifestyle changes,” she says. “These include maintaining a healthy weight, keeping active, limiting alcohol, eating a healthy diet and being smoke-free. In more serious cases, it can be managed with medication.”

How does the DASH diet lower blood pressure?

One of the most effective ways to lower your blood pressure through diet is to follow the DASH method. Dietary Approaches to Stop Hypertension (DASH), also called the high blood pressure diet, is a diet recommended for those who want to prevent or treat hypertension, reducing the risk of heart disease.

The DASH diet is similar to the Mediterranean diet, with a focus on eating fruits, vegetables, whole grains and lean meats, and a low intake of red meat, salt, added sugars and fat.

Scientists believe one of the prominent reasons those with high blood pressure enjoy benefits from this diet is because it reduces salt intake to 1 teaspoon (2,300mg) of sodium a day.

Does the DASH diet work?

Numerous studies to date have shown wide-ranging health benefits of the DASH diet. Research has consistently found that DASH lowers blood pressure in people with high blood pressure, but also those with normal blood pressure.

Other health benefits of the DASH diet include a decreased risk of some cancers and a lowered diabetes risk.

As with all diets, it takes a certain amount of willpower to stick to the recommendations, and some people may find following the diet a challenge over time. But even small changes count.

Start with the government recommendations to lower salt intake, increase fruit and veg intake and limit fat intake, or check out the Heart Foundation's five-step healthy eating pattern.

Always check in with your doctor before making dietary changes to lower your blood pressure.

Do you need help with your diet?

You may be eligible for The Healthy Weight for Life Essentials program, which supports HCF members to develop healthier habits, lose weight and prevent the onset of various chronic conditions like heart disease.

The Essentials program is available to HCF members who meet the program’s eligibility criteria including having:

• a Body Mass Index (BMI) of 28 and above
• multiple lifestyle risk factors like smoking, physical inactivity and poor nutrition
  
• HCF hospital cover.

Words by Sara Mulcahy and Karen Burge
Updated: June 2022