If you are worried about high blood pressure (BP), it might be time to stock up on bananas and broccoli instead of just cutting back on salt. A new study, published in the American Journal of Physiology-Renal Physiology, reveals that increasing your dietary intake of potassium could be more effective for managing BP than simply reducing sodium.
The research, conducted by scientists at the University of Waterloo, emphasises the importance of the potassium-to-sodium ratio in our diets—a factor that may hold the key to better BP regulation. High BP, or hypertension, affects more than 30% of adults globally and is a major contributor to heart disease, stroke, kidney failure and even dementia.
“Usually, when we have high blood pressure, we are advised to eat less salt,” said Prof Anita Layton who teaches applied mathematics, computer science, pharmacy and biology at the University of Waterloo and is the Canada 150 Research Chair in mathematical biology and medicine. “Our research suggests that adding more potassium-rich foods to your diet, such as bananas or broccoli, might have a greater positive impact on your blood pressure than just cutting sodium.”
Potassium and sodium are electrolytes that play crucial roles in the body, from regulating muscle contractions to managing water balance. But the modern Western diet, often heavy on processed foods, tends to be packed with sodium and sorely lacking in potassium.
“Early humans ate lots of fruits and vegetables, and as a result, our body’s regulatory systems may have evolved to work best with a high potassium, low sodium diet,” said Melissa Stadt, a PhD candidate in University of Waterloo’s department of applied mathematics and the lead author of the study. “Today, western diets tend to be much higher in sodium and lower in potassium. That may explain why high blood pressure is found mainly in industrialised societies, not in isolated societies.”
Using a novel mathematical model, the research team was able to simulate and predict how the potassium-to-sodium ratio influences BP across different body systems. The model also revealed important sex-based differences: men appear more prone to developing hypertension than pre-menopausal women but are also more likely to benefit from dietary potassium increases.
Beyond its specific findings, the study also showcases the power of mathematical modelling in medical research. These tools allow scientists to explore complex physiological interactions quickly, cost-effectively and without the ethical concerns tied to human or animal testing.
The findings offer a compelling case for rethinking how we approach hypertension – not just by reducing the ‘bad’, but by boosting the ‘good’. So, the next time you are watching your salt intake, consider reaching for a potassium-rich snack as well.