Phosphorous: the Good, the Bad, and the Ugly

We hear the phrase “vitamins and minerals” all the time, and we can probably name some of them. Vitamin C and Vitamin D are familiar, and we know we need iron and calcium. But what about phosphorous?

Phosphorous is good for us

Phosphorous is used by our bodies to build strong bones and teeth. It’s used to maintain and repair the structures of our bodies and for the production of DNA and RNA. It helps us use some other minerals and vitamins, including Vitamin D.

Phosphorous deficiency can be caused by malnutrition, anorexia, excessive alcohol use, certain drugs such as diuretics, and diseases like diabetes or Crohn’s disease. Symptoms of phosphorous deficiency include anxiety, fatigue, irritability, bone pain and fragile bones, bone diseases like rickets, anemia, loss of appetite, numbness, weakness, stiff joints, and irregular breathing. 

Too much phosphorous is bad for us

Phosphorous deficiency is rare. People in the United States are more likely to have too much phosphorous (hyperphosphatemia), not too little. While 85% of the phosphorous in our bodies is in our bones and teeth, there is also phosphorus in our cells and organs. Too much of it can lead to an increased risk of heart disease or stroke, and it can also lead to weak or painful bones. Hyperphosphatemia can also cause a drop in calcium. 

Usually, your kidneys keep phosphorous at the right level, making sure that extra phosphorous leaves your body. If you have poor kidney function, you might end up with excess phosphorus that your body can’t get rid of. There is also evidence that taking in too much phosphorous can be hard on your heart, even if your kidneys keep the right levels in your bloodstream. 

Hyperphosphatemia can also be caused by some medical procedures or by injuries or infections. The most common cause is kidney disease

Dietary phosphorous

If you suspect a phosphorus imbalance, you should discuss it with your doctor. However, you can address minor concerns by making sure that you have the right amount of phosphorous in the food you eat. People with CKD may need to avoid high-phosphorous foods. 

There are some problems with this. First, there is no simple rule for decreasing or increasing phosphorous. For example, you might hear that dairy products, whole grains, and meats are high in phosphorous. 

However, while milk is generally high in phosphorus, cheese can have anywhere from less than 100 milligrams of phosphorous to more than 1000 milligrams. Lean pork from the leg of the animal has twice as much phosphorous as pork loin. Roast beef is much higher than ground beef. Split peas are low in phosphorous but lentils have four times as much of the mineral. 

What’s more, bananas and kiwi fruits are high in phosphorous while pineapple and berries are low. There are even vegetables that are high in phosphorous. Cutting out whole categories of foods won’t work in this case. 

Also, many food manufacturers use phosphate additives. While chicken is generally a low-phosphorous choice, rotisserie chicken from the grocery store is usually high in phosphorous. In fact, processed foods in general tend to be high in phosphorous. This mineral is rarely included in nutrition labels, so it can be hard to find information about it. 

Ask your doctor for a target number for the amount of phosphorous you should try to eat in a day (1000 milligrams is a common goal). Then check on the specific foods you eat. Gradually you will learn which foods fit into your personal phosphorous goal.