Protein, found in meats, fish, poultry, dairy products, nuts and some grains, helps your body form muscle and tissue. But when your kidneys are not working well, the byproducts of protein breakdown can build up in your blood. This can make your kidneys work harder.
Some studies of low protein diets show that they can slow the progression of kidney failure. But other studies show that the diets do not help. Due to these mixed results, and the need to maintain good nutrition, doctors differ about the need to limit protein for people with chronic kidney disease (CKD). The answer is often moderation.
Many people with kidney disease find that they don't want to eat as much protein as they used to, because food doesn't taste the same. You may even need to make a special effort to eat enough protein and calories, because having kidney disease can reduce your appetite.
In all cases of chronic kidney disease, it's crucial to avoid malnutrition. A blood test for albumin, a form of protein, is a good way to tell if you are getting enough quality food. Your albumin level should be 4.0 g/dL or higher. If you notice weight loss, loss of appetite or other signs of poor nutrition, talk to your doctor or a renal dietitian.
So, how much protein do you need? K/DOQI national guidelines for kidney disease suggest a daily protein intake of 0.75 grams per kilogram of body weight for mild to moderate CKD (Stages 1, 2 and 3). Divide your weight in pounds by 2.2 to learn what you would weigh in kilograms. For example, 176 lbs. divided by 2.2 is 80 kg. If this were your weight, you would need 80 x 0.75, or 60 grams of protein per day.
In more severe kidney disease (Stages 4 and 5), the guidelines suggest considering 0.6 grams of protein per kilogram each day. Some doctors may advise even lower levels, which require close monitoring. If your diet includes very little protein, your doctor may prescribe supplements of nutrients you would normally get from protein, including ketoacids and/or amino acids.
To figure out how much protein is in the food you're eating, read labels and use nutrition reference tables. After a while, you'll have a good sense of how much protein is in a serving of meat, milk, etc., so you won't have to look everything up. A renal dietitian has special expertise helping people with kidney disease put together healthy meal plans. Ask your doctor about a referral to a renal dietitian. Check with your doctor or dietitian before making any changes to the protein level in your diet.
Ask your doctor or renal dietitian — the answer will often be yes. Phosphorus is a mineral found mostly in dairy products and meats. Your body uses it to form strong bones and teeth. But starting in the moderate, earlier stages of CKD, your kidneys begin to lose the ability to remove extra phosphorus from your body. Because too much phosphorus can harm your bones, it makes sense to eat less phosphorus.
Some experts think 800 to 1,200 mg. of phosphorus per day is a good target. Food labels are not required to list phosphorus, so you will need to talk to a renal dietitian or find a nutrition reference guide and look up foods. You'll soon learn the phosphorus values of the foods you eat most often.
If you are also on a lower protein diet, a low phosphorus diet is easier because foods high in protein tend to be high in phosphorus, too. Your doctor may want you to limit dairy servings each day and take a calcium supplement. Taken with meals, calcium supplements act as phosphate binders, because they lock on to extra phosphorus and keep your body from absorbing it.
Having the right level of potassium in your body helps all your muscles work smoothly — including your heart. So, to stay as healthy as you can, you need to keep just the right level of potassium in your blood (not too much, not too little). Keeping potassium at the right level all the time is one of the jobs that healthy kidneys do for your body. When kidneys fail, they start to lose this ability.
Your potassium level should be checked regularly with a blood test. If your levels are too high, your doctor will ask you to start a low potassium diet.
Many foods have potassium, but some such as avocados, dried fruits (including raisins, apricots and prunes), potatoes, oranges, bananas and salt substitutes are very high in potassium. If you need to limit potassium, your dietitian will help you learn which foods have more and which foods have less potassium.
Poor appetite is a common symptom of advanced kidney disease. Even if you are not hungry, it is important to eat and keep good nutrition. Well-nourished people with kidney disease stay healthier and live longer. As kidney function drops, you may notice that protein foods, such as eggs, meat, chicken and fish lose their appeal, or even taste funny. You need calories and quality protein to feel your best. To get good nutrition try to:
Finally, if you are in Stage 5 CKD and your appetite or nutritional well-being does not improve, this may be a sign that you should start dialysis. Many people find their appetite improves after some time on dialysis.
This site is for informational purposes only and is not intended to be a substitute for medical advice from a physician.
Please check with a physician if you need a diagnosis and/or for treatments as well as information regarding your specific condition. If you are experiencing urgent medical conditions, call 9-1-1