Why is too much salt bad for your heart?

At the Irish Heart Foundation, we aim to provide accurate and evidence-based information on heart health to help you make informed decisions about your health. One of the questions we get asked a lot is, what is the link between salt and heart disease and why is too much salt bad for you?

Salt in very small amounts (max one teaspoon a day) is essential for your health. It helps to maintain water balance, healthy blood pressure and healthy muscles and nerves. However, too much salt can lead to high blood pressure and the higher your blood pressure, the greater your risk of heart attack, stroke and other cardiovascular complications.

The maximum daily recommended amount of salt for an adult is 6 grams or one teaspoon but before you hit the salt cellar, be aware that the vast majority of the salt you get every day is already present in the food you eat. Many people exceed this level of salt intake and eat on average about 9-10 grams of salt per day. Children should eat much smaller amounts, depending on their age. School children should eat less than 4 grams per day and younger children should eat only the minimum amount of salt.

According to our expert dietitian Sarah Noone, “there is a substantial body of scientific evidence to show that high dietary salt intake can cause blood pressure to rise to unhealthy levels, especially as we get older as our bodies are less able to get rid of the excess salt we eat. There is also evidence that even small reductions in salt intake in the Irish diet, has the potential to produce a significant reduction in the average blood pressure of the population.”

“Although we know salt is a vital nutrient required for the body to function properly, the reality is the majority of us in Ireland are eating too much,” she said.

Sarah explained that most of the salt we eat does not come from the salt we add to food ourselves. In fact, she said that up to 70 per cent comes from processed foods, ready meals, fast food, canteen and restaurant food.

She said that two food groups: processed meats/fish (sausages, bacon, ham, salami or smoked salmon are some examples) and bread account for about 50 per cent of our salt intake from foods; while soups, sauces (ketchup, soya sauce), cakes, biscuits, pastries, cheese, spreads and breakfast cereals contribute the rest.

“Most nutrition labels at the back of the packet will tell you about the nutrients per 100g which is really useful to compare similar foods for salt content. Our handy IHF food shopping card is a useful tool to tell you whether a product is high or low in salt. Check out ‘What Are You Eating‘ for more information on reading labels.”

Finally, Sarah said that whether it’s pink, black, rock, crystal or flakes, all salt still has the same effect on your blood pressure. Although less refined salts might contain more nutrients than everyday table salt, these will only be in very small amounts and can be sourced from other foods in your diet.

“Replacing salt with a salt substitute will reduce the amount of sodium you add but won’t change your fondness for a salty taste. Flavour doesn’t only come from salt so instead we recommend trying alternatives such dried herbs, spices, black pepper, chilli or lemon to help reduce down salt intake,” Sarah advised.