Dr. MJ Bazos MD, Patient
Handout
Nutrition & Chronic
Renal Insufficiency
What are the
Kidneys?
The kidneys are the master
chemists of the body. Normally, there are two of them, one on either side of the
spine under the lower ribs. They are reddish brown in colour and shaped like
kidney beans. Each kidney is about the size of your clenched fist.
What do the Kidneys
Do?
Healthy kidneys do three essential
things. They remove wastes from the blood via the urine and return the cleaned
blood back to the body. They regulate the levels of water and different minerals
needed by the body for good health. They produce hormones that control other
body functions. Many other organs depend on the kidneys in order to work
properly.
What is Chronic Renal
Insufficiency (CRI)?
Chronic renal
insufficiency (CRI) is another term for kidney failure. This means the kidneys
are working at less than 50% of normal. CRI happens when kidney disease
interferes with the kidneys' ability to remove wastes from the body. Although
chronic renal insufficiency has many causes, diabetes and high blood pressure
are common ones..
What symptoms may
occur with CRI?
Usually, CRI starts
slowly and progresses over a number of years. During the early stages, there may
be no warning symptoms. Later, as the kidneys continue to fail, more waste
products like urea build up in the blood (this condition is called uremia) and
can make you feel sick.
Anemia can
also occur. This is a reduced amount of red blood cells in the body and can make
you feel very weak, tired and sometimes more sensitive to cold. Although people
with CRI become anemic because their kidneys have stopped making erythropoietin
(EPO), a hormone which helps make red blood cells, they may also have low levels
of iron in the blood and may need to take iron supplements.
What are the Treatments for
CRI?
In the early stages, the only
treatment needed may be a change in diet, control of blood pressure and/or the
use of some specific medications. When the kidneys are near the end of their
function (less than 10% of their normal rate), either dialysis or
transplantation is needed. This period is called end-stage renal disease or ESRD
How can Proper Nutrition
Help?
When your kidneys can no longer
do their job well, you have to control the kinds and amounts of food you eat.
Together, you and your dietitian will make a daily eating plan which will:
Meet your nutritional needs
Cut down the workload on your kidneys
Help keep the kidney function that is left
(before starting dialysis)
Control the
build-up of food wastes
Reduce symptoms
like fatigue, nausea, itching and bad taste in the mouth
Control the effects of high blood sugars
if you have diabetes
Each person has
different needs depending on their age, medical history and kidney function.
Your dietitian will work with you to design an individual daily eating plan
that's right for you. Together you can plan proper food choices to keep you
feeling as well as possible, and to try to slow the loss of kidney
function.
What are Healthy Food
Choices?
The following are the foods
and nutrients you will have to consider to help relieve symptoms, control blood
pressure and maintain health. These are protein, sodium, potassium and
phosphorus. If you have diabetes, it is also important to watch carbohydrates
for better blood sugar control.
Protein
Protein builds, repairs and maintains
your body tissues. It also helps your body fight infections and heal wounds. As
your body breaks down protein foods, a waste called urea is formed. If this is
not eliminated, too much urea in the blood may cause tiredness, nausea,
headaches and a bad taste in your mouth. If you eat too little protein, you may
lose muscle and weight, lack energy and have difficulty fighting infetions. Your
daily eating plan will provide enough protein for your body while limiting the
amount of urea formed. Foods like meat, fish, poultry, eggs, tofu and milk
are high in protein.
Sodium
Sodium affects your body fluids and
blood pressure. You need to control your salt intake and avoid foods with a high
sodium content. These include processed foods like "deli" meats, canned foods,
convenience and "fast" foods, salty snacks and salty seasonings.
To improve the taste of unsalted food,
you can use unsalted spices, herbs, vinegar and lemon.
Potassium
Potassium is a mineral which helps
your nerves and muscles work well. Some
potassium is necessary for good health, but too much can be dangerous. If the
potassium level in your blood is too high or too low, it can affect your
heartbeat. A very high level can cause the heart to stop beating. You may not
feel any warning symptoms. If necessary, your doctor and dietitian may recommend
you adjust how much potassium you eat. Your dietitian will give you a list of
how much potassium is found in various foods and help you make an eating plan.
This will help you make wise food choices to keep your potassium level within a
healthy range. Some high potassium foods are
potatoes, squash, bananas, oranges, tomatoes, dried peas and beans.
Phosporus (Phosphate)
Phosphorus is a mineral which normally
keeps your bones strong and healthy. However,
too much phosphorus may cause itchy skin or painful joints. When the kidneys
start to fail, your blood phosphate level will rise. Therefore, you may need to
limit certain foods which contain even a moderate amount of phosphorus. These
include milk, cheese and other milk products, and protein foods such as meat,
fish and poultry. However, you still need some milk products and protein foods
for overall good nutrition, so your dietitian will make sure you have enough of
these in your daily eating plan.
Generally, foods with very high levels
of phosphorus, such as seeds, nuts, dried peas, beans and processed bran
cereals, are not included in your daily eating plan.
Your doctor may also prescribe
phosphate binders. These medications bind with the phosphorus in your intestine.
The bound phosphorus will pass in your stool. You need to take phosphate binders
with the food that contains the phosphorus. Do not take phosphate binders at the
same time as iron supplements.
What
about Fluids?
Some people need to limit
their fluids while others can drink any amount they wish. As kidney function
decreases, the kidneys may not produce as much urine as before, and your body
may become overloaded with fluid. This can cause swelling of the legs, hands and
face, high blood pressure and shortness of breath. To relieve such symptoms, you
may need to limit your fluids. Your dietitian will build your fluid allowance
into your daily eating plan. Fluids include water, soup, juice, milk, popsicles
and gelatin.
Are Vitamin
Supplements necessary?
Normally, a
well-balanced diet will supply you with enough vitamins to keep you in good
health. With kidney problems, however, you may need additional vitamins. Vitamin
supplements must be prescribed by your doctor in collaboration with your
dietitian. This ensures that you get the right kind. Some over-the-counter
vitamins may be harmful.
What about
herbal remedies and “health
foods”?
Before you take any kind
of herbal remedy or "health food", discuss this with your dietitian and doctor.
These substances may create serious problems for someone with kidney
disease.