How much sodium do runners really need?

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You’ve just returned from a long run and can taste the salt on your skin. So you reach for a sports drink to rehydrate and replenish lost sodium and other electrolytes. But should you? On average, Britons consume 2.1g more than the recommended amount of salt per day (6g), so it may be time for runners to rethink their love affair with the mineral.

Too much sodium stresses your heart. Studies show that increasing dietary sodium raises blood pressure, which forces your arteries to become thicker to cope with the extra effort needed. ‘High blood pressure is a risk factor or for heart disease and stroke,’ says Dr Brian Strom, who chaired an Institute of Medicine committee that analysed the evidence behind current sodium recommendations. A 2014 New England Journal of Medicine report found that high sodium consumption is responsible for 1.65 million deaths worldwide every year.

But the answer isn’t to shun salt completely. ‘Sodium is a necessary electrolyte that helps your body maintain fluid balance during exercise,’ says Nancy Rodriguez, professor of nutritional sciences at the University of Connecticut, US. So how can you ensure your sodium intake falls within a healthy range?

The simplest way is to take stock of how much packaged and processed foods you consume, including breads, cereals, frozen and fast foods. Three-quarters of an average person’s sodium intake comes from processed sources – not from salting food during cooking or at the table. If pre-made or packaged foods make up a large part of your diet, it’s likely you’re over the healthy sodium limit. Check the nutrition label – according to the NHS, a high amount of salt is more than 1.5g per 100g. You’ll fall within a smart sodium range by doing two things: cooking more often at home and eating a diet full of fresh, minimally processed ingredients, including vegetables, lean meats and low-fat dairy. If you do that, an occasional bag of crisps – or mid-run energy gel or sports drink – will easily fit into your day.

Table salt

Available plain or iodised. Iodine, a mineral vital for thyroid function, is in some veg, dairy and saltwater fish, so you may not need extra from table salt.

Best for: Baking. Smaller crystals are ideal for making batter.

Sea salt

Made from evaporated seawater. It contains minerals, such as copper, iron and zinc.

Best for: Cooking. Fine sea salt works well in sauces and soups. The coarse kind adds bite to fish or meat just before serving.

Gourmet salts

They come in a range of crystal sizes and colours, including pink, beige, red and black. They also contain minerals. 

Best for: Mixing into a spice rub, or add a few flakes to cooked meat or veg.