Salt, sodium and potassium: key tips to eat a healthy balance


For a long time we've heard that having too much salt in our diets is a bad thing - and rightly so. A high salt intake can be one of the most powerful influences on blood pressure.

Sodium

Salt is made up of two substances, sodium and chlorine, and it's the sodium that can affect your blood pressure. This is because the sodium you eat affects how much water your kidneys extract from your blood.

The more sodium there is in your blood, the less water your kidneys will extract. As a result, your blood volume increases and because your circulation is essentially a closed system of tubes then up goes your blood pressure.

Potassium

There is however another side to the coin, which is potassium. The delicate balance between sodium and potassium governs the degree to which the kidneys extract water from the blood.

So while sodium is persuading the kidneys to leave water where it is in the blood, potassium has the opposite effect.

The moral of this story? Keep your salt intake down and make sure you eat lots of potassium-rich foods. (Do be aware that if you're taking certain medications, including blood pressure-lowering medicines, or have medical conditions such as chronic kidney disease, you may be advised to limit your potassium intake. If in doubt, speak to your doctor.)

Cutting back on the sodium

If you're cutting back on salt you may notice the lack of the flavour to begin with - but do persevere. Your taste buds will adjust within a couple of weeks and you'll not only be more sensitive to the taste of salt, you'll also become more aware of other flavours too.

Foods high in salt

Salt is used extensively in the foods that we buy so you need to be vigilant and familiarise yourself with foods that are particularly high in salt (sodium), especially:

• Processed meats like bacon, ham, sausages and salami

• Stock cubes and gravy granules

• Tinned and packet soups

• Tomato ketchup, soy sauce and mustard

• Microwave and frozen ready-meals

• Pickles and curry powders.

In the kitchen

• Use low-sodium alternatives to salty sauces and stocks

• Use alternative seasonings to add flavour to your food like fresh or dried herbs, spices, ginger, garlic, vinegar, pepper and chillies

• Lemon or limes help to bring out any salty taste in food.

At the table

• Try adding alternative seasonings to your food, such as lemon or lime juice, herbs, spices, vinegar and pepper

• Use a low-sodium salt - varieties can have up to two thirds less sodium as well as high levels of potassium.

Upping the potassium

Potassium can actually help to control blood pressure so it's a great substitute for sodium. Low-sodium salt brands often contain relatively high levels of potassium. So these are good options if you still want to use salt. Great natural sources of potassium include:

• Certain fruits, especially bananas, oranges, tomatoes, apricots and currants

• Certain vegetables, especially potatoes, sweet potatoes, asparagus, spinach, cabbage and sprouts

• Bran and wheatgerm

• Wholemeal pasta

• Tuna and salmon

• Yoghurt

• Milk and eggs

• Almonds and macadamia nuts

• Mushrooms.

Potassium supplements are not recommended as these can lead to excessively high potassium levels. You should instead simply increase your intake of potassium-rich foods.

A word of caution : although increasing potassium in your diet can help to control your blood pressure, you should of course talk to your doctor or specialist first if you are already taking blood pressure-lowering medication.