A healthy diet will help to control your blood pressure and blood sugar levels and reduce your risk of heart disease. These have a role in protecting your kidneys from further damage.
What is a healthy diet?
A well-balanced diet contains a variety of foods from the 5 different food groups, as shown in the Eatwell Guide. This will help you to get enough energy (calories) and protein, as well as essential vitamins and minerals.
The key messages are:
- Enjoy your food.
- Eat a wide variety of foods.
- Eat to be a healthy weight.
- Eat less salt.
- Only drink alcohol in moderation.
- Do not take a multivitamin or mineral supplement unless you have discussed this with your dietitian or pharmacist.
- Only follow a special diet for your kidneys if you are advised to by your doctor or dietitian.
Why do I need to change my diet?
Healthy kidneys normally control the level of substances and water in the body, which come from what we eat and drink. If your kidneys are not working as well as they should, you may not be able to control this balance. You may therefore need to change what you eat and drink to help with this. Most people with kidney problems will not need a special diet. This is usually only needed when you have more advanced kidney disease or you are on dialysis.
I have been told that cutting out salt might help. How can I do this?
Eating too much salt is linked with high blood pressure and heart disease, which can damage your kidneys. Everyone should aim to lower the amount of salt they eat to no more than 6g (around 1 level teaspoon) a day. Most salt is in the food we buy, and stopping the salt added at the table or in cooking will only reduce the amount by 10-20%, so it is important to check the labels.
To reduce the amount of salt you eat, try these suggestions:
- Cut down on very salty foods, such as bacon, ham, sausages, burgers or smoked fish
- Cut down on manufactured and processed foods, such as ready prepared meals, cooking sauces in jars, packet sauces and take-aways
- Reduce salty snacks such as crisps and nuts
- Watch out for the salt in bread and other bakery goods
- Try using fresh or frozen meat, fish and vegetables, rather than pre-prepared dishes or ready meals
- Do not add salt to your food at the table
- Cook without salt. There are lots of ways to add flavour to your cooking without using salt. Try adding fresh or dried herbs to dishes, or marinating meat and fish to give them more flavour
- Do not use salt substitutes, for example ‘Lo-salt’ or ‘Solo’, as these products contain a lot of potassium and are not suitable for people with kidney problems.
Remember: If you find cutting down on salt difficult, your taste buds adapt surprisingly quickly to dietary changes. Within a month you won’t be able to tell the difference.
What do food labels mean?
Understanding food labels can help you to make sensible choices when choosing foods. Food labels often show the salt content per 100g. The following table is based on the traffic light food labelling system, and can be used as a guide about a sensible amount of salt. Similar labels are used for fat and sugar.
Some food labels show the salt content per portion size of food. Bear in mind that you may eat more or less than the suggested portion size. Remember it is also important to consider the overall salt content of your meal.
Beware of foods labelled as “reduced salt”. Some of these may still be higher in salt than recommended.
0.3g or less salt per 100g
Between 0.3g and 1.5g per 100g
Over 1.5g salt per 100g
A good healthier choice
An OK choice
Eat only occasionally or as a treat
Can I drink alcohol with kidney problems?
Alcohol should only be drunk in moderation regardless of kidney problems. As a general guide, this means no more than 2 units a day for both men and women.
1 unit is the same as ½ pint of beer or lager, 1 small glass of wine, or one pub measure of spirits. Remember that some drinks that you pour for yourself may be larger than a pub measure.
It is a good idea to try and have at least 2 alcohol-free days per week, and not to binge drink.
It isn’t usually necessary for most people to avoid alcohol altogether. However, it is sensible to check with your doctor if it is safe for you to drink alcohol, particularly if you are taking any medications.
How will I know if I need to follow a special diet?
If you attend a specialist kidney clinic, your blood potassium and phosphate levels will be checked regularly. This is because damaged kidneys cannot clear these substances from the blood.
Some people with reduced kidney function may be advised to follow a special diet to help control the build-up of these substances in the blood. Your doctor will tell you if this is necessary in your case. You may be referred to a dietitian who will provide specialist advice to help you identify any foods you may need to cut down, and advise about suitable alternatives.
Do I need to lose weight?
It is particularly important to make sure that you are a healthy weight when you have kidney damage. If you are overweight, weight loss can help to reduce the risk of damage to the kidneys and will help to keep your blood pressure at a healthy level.
Healthy weight is measured by Body Mass Index (BMI), which shows the relationship between your weight and your height. A healthy weight is a BMI between 20 and 25.
If you are trying to lose weight you should do this sensibly by following a healthy, well-balanced diet, and trying to exercise regularly.
- Try to eat three regular meals each day and try to eat at similar times
- Only snack in-between meals if you are hungry. Try to avoid fatty, sugary or salty snacks
- Try to choose foods that are lower in fat and sugar
- Watch your portion sizes
- Try to eat plenty of fruit and vegetables every day – aim for “5-a-day” if possible. A portion of fruit is a piece of fruit such as an apple or orange, or a handful of small fruit such as grapes. A portion of vegetables is roughly 2 tablespoons.
Take care with grapefruit and grapefruit juice if you are on certain medications – check with your doctor or pharmacist.
What else can help me stay well?
Get active! It is important to keep active when you have kidney problems. Exercise has lots of benefits: it can help you to lose weight if you are overweight, help to lower your blood pressure and it is also great for increasing your self-confidence.
Any small changes to your activity levels will help. Try walking to the shops instead of driving or taking the bus, using the stairs instead of lifts or escalators or walk to the next bus stop instead of using the nearest one. If you want to try more exercise, this could include cycling, brisk walking, dancing, swimming, an exercise class, going to the gym or playing a sport such as badminton or tennis. Always check with your doctor if you are planning to start new exercise.
Where can I find out more information about a kidney-healthy diet?
- NHS Choices: Living with kidney disease
- NHS Choices: Live Well
- A dietitian: often people with early kidney disease will receive advice about healthy diet and lifestyle from their GP, practice nurse or hospital consultant. Not everyone with kidney problems will need to see a dietitian, but anyone who needs more detailed dietary advice can be referred to one. Kidney dietitians are experts in nutrition, and can provide advice that is individual to you, taking into account your personal needs, likes and dislikes, and cultural or religious requirements.
Remember, please ask your doctor or nurse to refer you to a dietitian if you have any concerns about your diet.