Benefits
Protein restriction lessens the protein load on the
kidney or liver, which slows down the continued devel-
opment of disease.Precautions
A person requiring a low protein diet should con-
sult a dietitian familiar with liver or kidney diseases to
provide guidance on developing an appropriate diet as
well as to learn how to follow the diet effectively. The
diet must meet the person’s nutritional needs, cut
down the work load on the kidneys or liver, help
maintain the kidney or liver function that is left, con-
trol the build-up of waste products, and reduce symp-
toms of the kidney or liver disease. Strict adherence to
the diet can be difficult, especially for children. Small
amounts of protein-containing food combined with
larger amounts of low or no-protein foods can be
used to make the diet more acceptable. Some persons
eliminate meat, eggs, and cheese from their diets rather
than measure the amounts of protein from these
foods. However, care must be taken to make sure
that adequate protein is included in a vegetarian diet
to provide for growth and development, including
building muscles and repairing wounds. Another
approach, since it is difficult to manage portion sizes
of foods other than milk, is to omit meats, fish, and
chicken from the diet and use milk as the primary
source of protein.
A person with both kidney disease and diabetes
must be careful to eat only low-to-moderate amounts
of carbohydrates along with monounsaturated and
polyunsaturated fats.
The human body reacts to protein deficiency by
taking amino acids (the building blocks of proteins)
away from muscle tissue and other areas of the body.
The process, in which the body basically metabolizes
itself, is called catabolism and leads to muscle loss and
weakness. The use of exercise and strength training is
recommended to counter the effects of muscle loss.Risks
The levels ofcalciumand phosphorus must be
monitored closely, for in persons with kidney disease,
phosphorus levels can become too high, while levels of
calcium can become too low. Monitoring of these two
mineralsmay require an adjustment in dietary intakes
of these minerals. Phosphorus is a mineral that helps
to keep bones strong. Too much phosphorus, how-
ever, may cause itchy skin or painful joints. Calcium is
required to maintain bone density andvitamin Disnecessary to control the balance of calcium and phos-
phorus. If changes to add these nutrients to the diet are
not adequate, then supplements and medications may
be required. If phosphorus levels are too high, a per-
son may have to take phosphorus binders that reduce
the amount of phosphorus that enters the blood
stream from the intestine. Dairy products as well as
seeds, nuts, dried peas, beans, and processed bran
cereals, are high in phosphorus, so the use of these
food sources may need to be limited.
A low protein diet may also be deficient in some of
essential amino acids (which are the building blocks of
protein), thevitamins niacin, thiamine, andriboflavin,
and the mineraliron(most people with advanced kid-
ney disease have severe anemia). Vitamin supplementa-
tion is dependent on the amount of protein restriction,
the extent of kidney damage, and the vitamin content of
food that is eaten. A person with kidney failure may
have decreased urine output. The amount of fluids a
person needs to drink is based on the amount of urine
produced daily, the amount of fluid being retained, the
amount of sodium in the diet, the use ofdiuretics,and
whether the person has congestive heart failure.
In persons with advanced kidney disease, a low
protein diet may lead to malnutrition. The person may
lose muscle and weight, lack energy, and have diffi-
culty fighting infections. Daily calorie intake is
dependent on the amount needed to prevent break-
down of body tissues. Body weight and protein status
should be monitored periodically, which in some cases
may be daily. Extra calories can be added to the diet by
increasing the use of heart-healthy fats, eating candy
and other sweet foods, such as canned or frozen fruits
in heavy syrup.Research and general acceptanceVery low protein diets coupled with amino acid
supplements have been shown to slow down the pro-
gression of and even cure certain types of kidney dis-
ease in persons in early stages of the disease. In adultsQUESTIONS TO ASK YOUR
DOCTOR Where do I find out about this diet?
What types of medical monitoring and oversight
do I need?
Where can I find support and information?
What types of side effects should I watch out for?Low-protein diet