A new study suggests that the DASH diet, one of the best-known eating plans for lowering blood pressure, may not significantly increase blood potassium levels in adults taking several common hypertension medicines.

The findings are preliminary. They have been presented at the American Heart Association’s Hypertension Scientific Sessions 2026 in Virginia and have not yet been published in a peer-reviewed journal. Even so, the analysis addresses an important clinical question: can people taking medicines that may raise potassium safely follow a diet rich in fruit, vegetables, beans, whole grains and low-fat dairy?

For many patients, the answer may be yes, provided they have normal potassium levels at the outset and do not have advanced kidney disease.

The Dietary Approaches to Stop Hypertension, or DASH, diet has long been recommended for people with high blood pressure. It emphasises fruit, vegetables, whole grains, beans, nuts, fish, poultry, vegetable oils and low-fat dairy foods. It encourages people to reduce salt, sugary foods, fatty products, red meat and processed meat.

It is naturally high in potassium. That is often helpful. Potassium can support healthy blood pressure, especially when people also lower sodium intake. However, high potassium levels in the blood can become dangerous. The condition, known as hyperkalaemia, can interfere with the heart’s electrical activity and trigger serious rhythm problems.

The issue matters for people taking certain blood pressure medicines. ACE inhibitors, angiotensin receptor blockers, known as ARBs, and potassium-sparing diuretics can all increase potassium levels. These medicines are widely used for hypertension, heart failure, kidney disease and other cardiovascular conditions.

Most people take them safely with routine clinical monitoring. Yet the risk of hyperkalaemia rises in people with chronic kidney disease, reduced kidney function, diabetes, dehydration or previous high potassium readings. Clinicians have therefore often advised caution when recommending potassium-rich foods to patients using these treatments.

The latest analysis provides some reassurance, although it does not remove the need for individual medical advice.

Researchers examined data from the GoFresh and GoFresh Rx randomised trials. The new secondary analysis included 356 adults with an average age of 53. Roughly 70% were women. At the start of the study, participants had systolic blood pressure readings between 120 mm Hg and below 150 mm Hg. Their diastolic readings were below 100 mm Hg.

Participants had differing degrees of kidney function. Some were taking blood pressure medicines and some were not.

Half received weekly deliveries of groceries based on DASH principles for three months. They also received weekly nutrition counselling. The other half were given a cash payment every four weeks to buy groceries, without nutrition counselling.

Researchers measured potassium levels in participants’ blood at the beginning of the study and after 12 weeks. They found no significant rise in potassium associated with the DASH grocery programme. This remained the case among people taking medicines that are known to increase potassium.

The study also found no meaningful changes in kidney function during the three-month period.

That result is noteworthy because the kidneys regulate potassium levels. Healthy kidneys remove excess potassium through urine. When kidney function declines, the body may struggle to clear potassium effectively, allowing it to build up in the blood.

The findings suggest that a DASH-style dietary pattern did not cause potassium to reach unsafe levels in this particular group. Results did not differ significantly between those receiving structured grocery deliveries and nutrition support and those receiving cash to buy food independently.

Experts say this could help reduce unnecessary uncertainty around heart-healthy diets. Patients may be told to eat more fruit, vegetables and beans, then become concerned when they discover that many of these foods contain potassium. Bananas, potatoes, leafy greens, tomatoes, pulses, yoghurt and dairy products can all contribute to potassium intake.

For someone using an ACE inhibitor or ARB, this can create confusion. Some may limit healthy foods unnecessarily. Others may consider changing or stopping medication without medical guidance. Neither approach is advisable.

The study does not show that every patient taking blood pressure medicine can follow DASH without concern. It indicates that the diet may be appropriate for many adults with normal potassium levels before starting the programme.

There are important limitations. The researchers did not include people with stage 4 or stage 5 chronic kidney disease. These are advanced stages of kidney impairment, where the risk of hyperkalaemia is substantially higher. The study also excluded people whose potassium levels were already above the normal range.

Therefore, the results cannot be applied to those groups.

The research was short term, lasting 12 weeks. It provides useful evidence about early changes in potassium and kidney function, but it cannot establish long-term safety or health outcomes. Larger studies with longer follow-up will be needed. Future research should include people with moderately reduced kidney function and those at greater risk of high potassium.

Despite these limits, the study supports existing evidence that DASH can be an effective, accessible dietary strategy for managing blood pressure.

The original DASH trial, published in The New England Journal of Medicine in 1997, found that a dietary pattern rich in fruit, vegetables and low-fat dairy lowered blood pressure. A follow-up study found that reducing sodium while following the DASH diet produced even greater improvements.

Subsequent research has linked DASH-style eating with improved cardiovascular health and a lower risk of heart disease. Its benefits are likely to come from its overall pattern rather than from any single nutrient. It promotes fibre-rich foods, healthier fats, fewer highly processed products and lower sodium intake.

The diet is not intended as a replacement for medication. It works best as one part of a broader approach to cardiovascular health. Blood-pressure medicines, regular physical activity, sleep, smoking cessation, moderate alcohol intake and routine health checks remain important.

People taking blood pressure medicines should also be cautious with potassium supplements and salt substitutes. Some low-sodium salt alternatives contain potassium chloride rather than sodium chloride. They may be suitable for certain people but can be risky for those with kidney disease or medicines that increase potassium. A pharmacist, GP, cardiologist or renal specialist can advise whether they are appropriate.

Adopting DASH does not require an immediate, strict overhaul of every meal. Gradual changes often last longer. Adding an extra serving of vegetables to lunch or dinner is a useful first step. Choosing fruit instead of a sugary snack may help. Swapping white bread or refined cereal for wholegrain versions can make a difference over time.

Sodium reduction also deserves attention. Much of the salt in modern diets comes from packaged or prepared foods rather than the salt shaker. Soups, sauces, breakfast cereals, breads, takeaway meals, processed meats and savoury snacks can contain considerable amounts. Reading food labels and comparing products can help people choose lower-salt options.

Simple meals can fit DASH principles. Porridge topped with fruit and yoghurt offers whole grains, dairy and produce. A bean and vegetable soup with wholemeal bread can provide fibre and protein, although canned ingredients should be checked for salt. Grilled fish or chicken served with vegetables and brown rice is another straightforward option.

Access remains an important issue. Fresh food, low-sodium products and wholegrain choices can cost more or be harder to find in some areas. The GoFresh studies are relevant partly because they recognised this barrier. They examined not only dietary advice but also whether providing food or financial support could help people make healthier choices.

The central message from the analysis is encouraging but measured. For adults with normal potassium levels and without severe kidney disease, following a DASH-style diet did not appear to cause a significant increase in blood potassium while using common blood pressure medicines.

That may reassure patients and clinicians who have been uncertain about combining these treatments with a potassium-rich diet.

It is not a reason to ignore blood tests, kidney health or individual medical guidance. People with chronic kidney disease, previous hyperkalaemia or concerns about their medicines should speak with their healthcare professional before making major dietary changes.

For many others, however, the evidence points in a positive direction. A diet centred on fruit, vegetables, beans, whole grains, lower-sodium foods and lean protein may support better blood pressure control without adding meaningful potassium risk.