The human body relies on the presence of dozens of vitamins and minerals to function properly. These micronutrients act on a cellular level to affect a variety of physiological processes. Among the trace minerals, phosphorus is one of the most important for its role in bone health and energy production. Learning what foods contain phosphorus can ensure that you get enough of this valuable mineral.
What Is Phosphorus?
The second most prevalent mineral in the human body, phosphorus is a chemical element that is actually highly reactive in its free form (Madell, 2015). Most of the phosphorus we get in our diets actually comes from the phosphate PO4, a more stable compound that contains phosphorus. The body uses this phosphorus for a variety of physiological processes.
Physiological Role of Phosphorus
Phosphorus is found in every cell in the human body (Calvo, 2014). For instance, phosphorus is a critical component of the phospholipids that make up the cellular membrane. The primary energy compound in cells, adenosine triphosphate, also includes phosphorus. Thus, without phosphorus we would be unable to survive.
Phosphorus is also important for creation of nucleic acids. Nucleic acids are the building blocks of DNA, the genetic material that contains the information needed to create new proteins. Additionally, the mineral is also needed to create new enzymes, hormones, and molecules involved in cell signalling. Without these entities, our bodies would be unable to perform basic metabolic processes.
In addition to providing structural integrity for cells and acting as a critical component of the cell’s energy cycle, phosphorus plays a major role in bone health. One of the most important physiological roles of phosphorus is to add structural integrity to bone tissue. In fact, 85% of the body’s phosphorus is found in the bones and teeth (Erlich, 2015).
Recommended Daily Intake of Phosphorus
The recommended daily intake of phosphorus is intended to ensure that you will not develop problems related to phosphorus deficiency. Adult men and women should aim to get 700 mg of phosphorus every day (Calvo, 2014). Adult pregnant or breastfeeding women need the same amount, while women younger than 18 who are pregnant or breastfeeding should aim for 1,250 mg of phosphorus daily.
Best Dietary Sources of Phosphorus
Phosphorus can be found in a variety of foods in the human diet. For most of us, eating a balanced and varied diet ensures that we get plenty of phosphorus. Indeed, risk of phosphorus deficiency is very low in the United States and most developed countries. Following is a list of foods that can help you achieve the recommended daily intake of phosphorus (Calvo, 2014):
Salmon (3 ounce serving): 315 mg of phosphorus
Plain nonfat yogurt (1 cup): 306 mg
Skim milk (1 cup): 247 mg
Turkey (3 ounces): 217 mg
Halibut (3 ounces): 244 mg
Chicken (3 ounces): 135-196 mg
Lentils (½ cup serving): 178 mg
Almonds (1 ounce): approximately 23 nuts): 136 mg
Peanuts (1 ounce): 108 mg
Egg (1 large): 86 mg
Whole wheat bread (1 slice): 68 mg
Signs and Symptoms of Phosphorus Deficiency
Phosphorus deficiency is relatively uncommon in the modern American diet (Erlich, 2015). If phosphorus levels dip too low, the kidneys reabsorb phosphorus to make up the difference. However, phosphorus deficiency (also known as hypophosphatemia) may occur in people with respiratory alkalosis, diabetics who have experienced an episode of diabetic ketoacidosis, alcoholics, or anorexic patients. People with digestive disorders such as Crohn’s disease or ulcerative colitis may also be at risk for phosphorus deficiency. The most common signs of phosphorus deficiency include (Calvo, 2014):
Loss of appetite
Rickets (in developing children)
Numbness or tingling in the extremities
Immune system problems culminating in higher susceptibility to infection
Considerations for Dietary Phosphorus Intake
When working to ensure that you get enough dietary vitamins and minerals, it is important to ensure that these micronutrients are highly bioavailable. Bioavailability refers to your body’s ability to absorb and use the micronutrients contained in a food. For instance, a food could be high in phosphorus, but if it cannot be digested by the body, it would have low bioavailability.
Seeds, beans, peas, and nuts are high in phosphorus. However, the form of phosphate in these plant seeds is called phytate (Calvo, 2014). Humans lack the enzymes to efficiently pull phosphorus from the phytate compound. Thus, only about half of the phosphorus in phytate is bioavailable. The phosphorus in animal products is more bioavailable. For vegetarians, eating leavened breads can help to improve phosphorus intake. This is because the yeast in bread has the enzymes needed to pull phosphorus from phytate (Calvo, 2014).
If you are at risk of developing phosphorus deficiency, there are supplements available to ensure you get enough. Taking a daily phosphorus supplement may increase your supply of bioavailable forms of this mineral. However, it is possible to get too much phosphorus (Ehrlich, 2015). This is most common in patients with kidney disease. Getting more than 4,000 mg of phosphorus per day may have toxic consequences (Calvo, 2014).
Phosphorus is just one of the minerals you need to keep your body healthy. Particularly for bone health, calcium is also important. When trying to boost your phosphorus intake, pay careful attention to how much calcium you receive. Having a low calcium-to-phosphorus ratio may increase your risk of bone problems, particularly for women with osteoporosis (Calvo, 2014). Meanwhile, having a high intake of calcium and phosphorus can be protective of bones and may reduce your risk of osteoporosis.