Importance of salt restriction for renal patients

Salt in your diet

What happens if you eat too much salt?

Too much salt (sodium chloride) in your diet can increase your blood pressure, leading to an increased risk of heart disease and stroke. It does this by causing your body to hold on to extra fluid. It can also make you thirsty, so that you want to drink even more. This effect is particularly important if you are on a fluid restriction. Reducing the amount of salt in your diet will make it easier to control your fluid intake, help to reduce your blood pressure and your risks of heart disease.

How much salt should you have in your diet?

You should aim to have less than 6g of salt a day in your diet. That’s about a level teaspoonful and includes all the salt you eat throughout the day including salt in the foods you buy, such as cereals and bread.

What is the best way to reduce salt in your diet?

The first step is to stop adding salt to your food at the table and to food you are cooking.

The next step is to cut down on foods that have a relatively high salt content, such as:

• tinned foods (for example soup and baked beans)
• dried packet products (for example pasta packs and soup)
• savoury snacks (for example crisps, salted nuts and pretzels)
• sauces (for example tomato ketchup, brown sauce, soy sauce and Worcester sauce)
• seasonings (for example Oxo cubes and yeast extract)
• smoked meats and fish

A good target would be aim for fewer than two of any of the above foods per week.

Label reading

It is worth reading the labels on foods, as the amount of salt that they may contain can vary considerably depending on the brand. The easiest way to do this is to look at the salt content per 100g of product. Salt can also be written as sodium or 'Na'; both of these terms are used on packaging. (Note: To convert sodium to salt, simply multiply the sodium value by 2.5.)

• If a product has more than 1.5g salt (or 0.6g sodium) per 100g product it has a high salt content.
• If a product has less than 0.3g salt (or 0.1g sodium) per 100g product it has a low salt content.
• Anything between these two levels is considered to have a medium salt content.

It is also worth looking at how much salt is in each serving as even a ‘low salt’ product can add up to a lot if you eat enough of it!

Initially, reading labels can take time as you will be comparing the foods you currently eat to other brands. However, you will soon learn which ones are most suitable, and your shopping time will soon be the same as it always was. You will only need to check each time you pick a product that is new or unknown to you.

Simplifying label reading

If you find this all too confusing, or if you are in a rush or the print on the label is too small, looking at the ‘front of package labelling’ can be useful. This is often displayed as a 'wheel' or a 'traffic light', and contains information on fat, sugar and salt. In this instance you need only to look at the salt value:

• if it is labelled red it has a high salt content
• if it is amber it has a medium salt content
• if it is green it has a low salt content.

You should aim to make most of your diet up with low to medium salt containing foods.

Are all salts equally bad for you?

There are many different types of salt, including rock salt, table salt and sea salt. All of these contain the same amount of sodium, which is what causes your blood pressure to rise, so they should all be restricted in your diet. Salt alternatives such as Lo-Salt or Solo should also be avoided as they contain potassium, the level of which can often be raised in renal patients.

Alternative flavourings

An excellent way to flavour foods, and to make it easier to cut down on salt, is to add herbs and spices such as pepper, garlic and ginger. Your dietitian will be happy to provide you with a list of ideas.

Other information

If you are struggling to cut down on the salt in your diet, your dietitian will be able to provide individual advice and support to help you make these changes and set realistic targets for you.