Sodium and early stage kidney disease
Sodium is a necessary mineral for a healthy diet. Sodium attracts and holds water to help prevent dehydration. Sodium is one of the body’s three major electrolytes (the other two are potassium and chloride). Electrolytes control fluid amounts in the body’s tissues and cells. Salt (which contains both sodium and chloride) is a major source of these electrolytes. Aside from controlling fluids, salt and electrolytes also:
- Regulate blood pressure and blood volume
- Transmit nerve impulses
- Influence muscle contraction and relaxation
Very little sodium is needed to maintain healthy body functions. Yet the typical American diet contains too much sodium, which can lead to health complications. Early stage kidney disease is one of them.
Kidneys regulate the amount of sodium kept in the body. Healthy kidneys eliminate excess sodium from the blood. But when kidney damage occurs, a portion of the kidneys’ filters no longer work and sodium can accumulate in the blood. Because sodium holds fluid, the blood increases in volume, making the heart work harder to move blood through the blood vessels. Increased blood pressure damages the blood vessels in the kidneys and causes more kidney damage.
Managing high blood pressure is important in early stage kidney disease, because it can help decrease further damage to the kidneys. Your doctor will monitor your blood pressure and may prescribe a low sodium kidney diet.
Other sodium-related complications for people with kidney disease include:
- Edema – swelling in the legs, hands and face
- Heart failure – increased blood volume can lead to an enlarged, weakened heart
- Shortness of breath – fluid builds up in the lungs
A low sodium kidney diet and early stage kidney disease
Low sodium kidney diets for some people with early stage kidney disease suggest 2,000 mg to 3,000 mg per day. Even lower amounts may be prescribed if additional health problems exist. Your renal dietitian will help determine the right amount of sodium for you. You will need to be more aware of the foods you eat. There are three main sources of sodium in the American diet:
- Processed and prepared foods
- Sodium-containing dressings, sauces and condiments including salt
- Natural sources of sodium
Start by looking at the nutrition labels of the food in your pantry or at the grocery store. Here are some sodium based ingredients you should limit or avoid when on a low sodium kidney diet:
- Monosodium glutamate (MSG) – seasoning used in many restaurants, canned and frozen foods
- Baking soda (sodium bicarbonate) – used to leaven baked goods, flavor vegetables and aid with indigestion
- Baking powder – used to leaven baked goods
- Sodium nitrite – used in curing meats and sausages
- Salt, sea salt, kosher salt – seasoning added to increase flavor
- Soy sauce – used to season and add flavor
Reducing sodium for the kidney diet
Here are some simple ways to cut the sodium in your diet when you have early stage kidney disease:
- Reduce your sodium intake gradually.
- Eat more fresh foods and fewer processed food.
- Read the nutrition label on foods for sodium information. This also goes for beverages that may contain high amounts of sodium.
- Limit bread products as these contribute a significant amount of sodium.
- Buy low sodium products.
- Reduce or remove salt from recipes. You can use herbs and spices instead. Certain recipes for baked goods are the only exception to this rule. Ask your dietitian for help.
- Take the salt shaker off the dining table.
- Limit salad dressing and condiments or use low sodium products.
- When dining out, request that your food is prepared without salt or MSG. Ask for condiments, salad dressings and sauces on the side.
- Avoid cured or salted meats, such as ham, sausage, bacon, hot dogs and luncheon meats.
- Also avoid soup from a restaurant; it can be very high in sodium.
- If you use a potassium-based salt substitute check with your dietitian to be sure it is safe.
- Keep an accurate food journal to track your sodium and other nutritional intake.
- Try to avoid frozen dinners and other highly processed convenience foods.
- Avoid commercial soups (canned, dried or frozen). They contain high amounts of sodium and may also contain added potassium.
- Report any sudden changes of weight or swelling to your doctor and dietitian.
Sodium is necessary for a healthy diet, but too much can cause high blood pressure, which is the second leading cause of kidney disease. A low-sodium kidney diet will be recommended by your doctor and a renal dietitian can help you make food choices that are beneficial to your health. Reading food labels, reducing salt and high sodium ingredients in certain recipes and eating more fresh foods can help you reduce sodium when you have early stage kidney disease.
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