When it comes to dairy products in our everyday food intake, most people would say that they have milk or other dairy products daily, if not more! Milk, cheese, cottage cheese, yogurts, pudding and ice cream are some of the favorite dairy products of young and old alike. Dairy products are naturally abundant in protein, B vitamins, calcium, phosphorus and potassium. All of these nutrients are important for our body’s many functions.
Healthy kidneys help remove waste products and extra fluid from the blood and help balance the levels of salt and minerals in the body. As kidney function declines, protein waste products, fluid, salt and minerals can rise to unsafe levels in the body and this might mean that dairy products must be limited.
A closer look at these key nutrients in dairy foods will help those with decreased kidney function understand the importance of limiting dairy foods.
Dairy products are a great source of protein. Protein helps build muscle, and maintain our internal organs. Protein also helps to heal wounds and fight infections. We need protein sources in our diet daily, so if protein needs to be limited due to decreased kidney function, it is important to balance the right amount of protein from all food sources, including dairy, meats, eggs, nuts, and other non-meat sources. Some of these non-dairy protein sources are high in some of the other minerals that may also be limited, such as potassium, and phosphorus, so it is important that a renal (kidney) dietitian help plan which protein sources can be eaten and how often.
Dairy foods are usually the main source of calcium in our diet. Calcium is needed for keeping bones and teeth strong and for helping muscles contract, for some blood clotting functions and for several nerve functions. When decreased kidney function means dairy products need to be limited, calcium intake is limited. In order to obtain enough calcium to meet the body’s needs every day, a calcium supplement may be necessary. The right type and right amount of a calcium supplement is best determined by a renal doctor or dietitian.
Phosphorus is a mineral found in many foods and is essential for the formation of bones and teeth. It plays an important role in how the body uses carbohydrates and fats for energy. It helps the body use protein for the growth, maintenance, and repair of cells and tissues. Healthy kidneys help remove any extra phosphorus that is not used by the body each day. Reduced kidney function may mean that foods high in phosphorus need to be limited to control how much phosphorus gets into the bloodstream. High phosphorus levels in the blood can cause bones to lose calcium, becoming weak and brittle. High phosphorus blood levels can also cause skin to itch as the body is trying to get rid of it through the skin. Medicines called phosphate binders actually help “bind up” phosphorus from foods while they are still in the stomach, and help remove phosphorus from the body through the stool.
Potassium is abundant in most dairy products as well as in many other foods such as certain fruits and vegetables, nuts, chocolate and certain salt substitutes. Potassium helps regulate the heart beat and help muscles contract. Potassium levels in the blood can build up when kidney function decreases, and then can cause heart and muscle problems. Medicines that can help bind up potassium are not used on a regular basis like phosphorus binders because potassium binders cause diarrhea and dehydration. So limiting dairy products in order to control potassium levels in the body is necessary.
B Vitamins are a group of eight vitamins that help with the body’s ability to produce energy from foods eaten, and help maintain healthy cells and tissues. Some of the B vitamins such as B12, thiamine and riboflavin are abundant in milk products. An 8 ounce glass of milk contains the full daily requirement for B12 for most age groups. Therefore, when it is necessary to limit milk and other dairy products from the diet, there is a concern for some B vitamin deficiencies, especially with B12. A Vitamin B complex supplement is usually prescribed by a renal doctor to help replace those B-vitamins that are usually lacking in those who must limit dairy products due to kidney dysfunction.
It is very now very easy to see that although dairy products are rich in many nutrients, these same nutrients may need to be intentionally limited while others may be limited unintentionally when limiting dairy products. A renal dietitian is a great resource in helping plan a diet that balances all aspects of the diet for kidney patients.
Linda Ulerich, RD