How to balance sodium and potassium in your diet

Many of us have been told for years that the key to heart health is simply “cutting out salt.” While reducing your salt intake is a vital step, focusing only on what to remove misses a crucial part of the picture. True heart (cardiovascular) support comes from the balance between two essential minerals, namely: sodium and potassium.

These two nutrients work together like a see-saw to regulate your fluid levels, circulation, and blood pressure. Understanding how to manage this internal duo can significantly support your long-term wellbeing and help you feel more in control of your heart health.

How sodium and potassium work in the body

To understand why balance matters, it helps to look at what these internal minerals do individually. Sodium is essential for controlling fluid balance and sending nerve signals throughout your body.

Potassium, on the other hand, is an unsung hero when it comes to muscle function support, maintenance of a steady heart rhythm, and helping in making your blood vessels relax.

When these two minerals work together in harmony, they influence your blood pressure and reduce the strain on your cardiovascular system. However, the modern diet often flips this see-saw picture the wrong way: we tend to consume far too much sodium while getting too little potassium.

Why imbalance affects blood pressure

When your sodium levels are too high, your body holds onto extra fluid, which increases your overall blood volume. Imagine trying to pump more fluid through the same-sized pipes. This extra volume naturally raises the pressure against your blood vessel walls.

Potassium acts as the natural counter-balance. It encourages your kidneys to excrete excess sodium and helps relax the walls of your blood vessels, which eases that pressure. If your diet has an unhealthy ratio of these minerals, you face an increased risk of hypertension (high blood pressure) and heart disease.

“There is credence to the theory that increasing potassium levels can lower blood pressure. By altering the ratio of sodium to potassium, e.g., lowering sodium and raising potassium, this can lead to reduced blood pressure and heart problems”

– Dr Piya Sen Gupta, Diabetes and Endocrinology Specialist

Common sources of high sodium in everyday diets

Most of the sodium we eat doesn’t actually come from the salt shaker on the table. Instead, it is often tucked away in:

• Processed and packaged foods, which are frequently preserved with high amounts of sodium
• Ready meals and takeaways, which can easily exceed the recommended daily limit of 6g of salt (about one teaspoon)
• Bread and condiments, e.g., staples like bread, soups, sauces, and gravy, are common culprits
• Cured meats and cheeses, such as bacon, sausages, and aged cheeses like Parmesan or Roquefort are naturally high in sodium
• “Hidden salt” of many foods that do not even taste salty at all, e.g., some breakfast cereals, can contain surprisingly high amounts of sodium

Foods naturally rich in potassium

The good news is that you can support your heart by adding delicious, whole foods to your plate that are naturally rich in potassium, such as:

• Fruits: Bananas are well-known, but oranges, apricots, kiwi, and avocado are also excellent choices.
• Vegetables: Spinach, sweet potatoes, tomatoes, and broccoli are potassium powerhouses.
• Legumes: Beans and lentils provide a double win of potassium and fiber.
• Nuts and seeds: Great for snacking or adding crunch to meals.
• Whole grains and dairy: Foods like oats and yogurt can also contribute to your daily goals.

Simple ways to improve your sodium-potassium balance

Improving the balance between sodium and potassium doesn’t require an “all-or-nothing” approach. Small, sustainable shifts or transitions for that matter, can make a significant difference.

Reduce excess sodium

• Choose fresh over packaged foods. Fresh produce should be preferred to avoid the hidden salt in processed goods
• Read the labels properly when buying food. Check for sodium content on the packaging. For ready meals, be aware that many of these foods contain at least one-third of your daily salt limit in a single serving.
• Get creative with seasoning. Use herbs, spices, and lemon juice to flavour your food instead of reaching for the salt.
• Watch the “hidden” extras. Limit processed snacks and be mindful of the portion sizes when using sauces.

Increase potassium naturally

• The “every meal rule” where you try to add a piece of fruit or a portion of vegetables to every meal you eat
• Embrace whole foods, e.g., pulses, beans, and unprocessed grains in your cooking
• Cook at home where you prepare from scratch gives you full oversight of what you use in your ingredients

Many foods and drinks can help reduce blood pressure, including olive oil, beetroot juice, coconut water, and turmeric. These are beneficial as they are also rich in potassium, fibers, and magnesium.

Ms. Raquel Britzke, Doctify-rated Registered Dietitian and Sports Nutritionist

Special considerations

While increasing potassium is generally helpful, it isn’t a “one-size-fits-all” recommendation. There are few important considerations you need to be mindful about, including:

• Kidney health: People with kidney disease need specific guidance, as their bodies may struggle to process any excess potassium
• Medications: Certain medications can affect how your body retains or loses potassium
• Consult a professional: It is essential to check in with your general practitioner (GP) or cardiologist before making major dietary changes or starting supplements. High potassium levels can be just as dangerous to the heart as low levels if not managed correctly

When to seek medical advice

It is important to know your numbers and listen to your body really carefully. You should consult a healthcare professional if you experience:

• Persistently high blood pressure with general readings above 140/90 mmHg (although this differs what age bracket you belong)
• Irregularities or fluttering sensation of heart beat (heart rhythm symptoms)
• Unusual swelling, which is a result of significant fluid retention leading to swelling in the limbs
• Pre-existing medical conditions, particularly known kidney or heart issues

Conclusion

Supporting your blood pressure doesn’t have to mean following an extreme or restrictive diet. By making small, mindful shifts toward fresh foods and better balance, you can provide your heart with the protection it needs. Remember that lifestyle habits, e.g., how and where you eat, are just as important as the food itself.

Find the best cardiologists in the United Kingdom, or or search for the best specialists in your locality:

• Cardiologists in London
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• Cardiologists in Harley Street

Medically Reviewed
Last reviewed on 27/01/2025