Every now and then a patient will ask me about phosphates and if they should be concerned about their health risk. The answer to that question is a little tricky.  On the one hand, phosphorus, from which phosphates are derived, is a mineral that is crucial to all humans. Our bones, teeth and muscles need it to maintain their structural integrity as well as their function.

On the other hand, phosphates, as a byproduct of phosphorus, are created through a chemical process of mixing phosphorus with either calcium, sodium, potassium, aluminum and are used in foods and products all around us. As such, could you be overexposed to them? Here’s what I advise my patients.

Phosphates In Your World

The food you eat:  When my patients ask me about possible phosphates in the food they eat, I tell them that phosphates as preservatives have been used for a long time in food and have a GRAS (generally recognized as safe) clearance from the U.S. Food and Drug Administration as well as the World Health Organization.  Food additive phosphates should not be confused with organophosphates, tribasic sodium, or tribasic potassium phosphates, which are highly toxic.

However, you may be happy to know that with the trend towards more natural food preparation and decrease in general of all food additives, phosphates as food preservatives have decreased significantly in the last 15 years.

Of course, there are also naturally occurring sources of phosphate, or phytate based phosphates, which are found in the highest amounts in nuts, grains, meat, milk and eggs.  I always recommend my patients get the natural source of a mineral as your body can assimilate it best.  That said, calcium, magnesium and potassium added types of phosphates can provide these needed minerals to your diet if they are lacking from natural sources.  If you stick, primarily, to natural (organic if possible) food sources, you should not exceed the recommended minimum/maximum daily intake levels of phosphorus/phosphates (see below).

Environment: As I said earlier, phosphorus is necessary for human life. It is also essential to animal and plant life survival.  However, when phosphorus levels become too high in the environment from agricultural run-offs, due to fertilizers and animal waste into streams and lakes, algae can overgrow and cause delicate ecosystems to go seriously out of balance.  It can also up the limits of phosphates in our drinking water which becomes concerning.

“Nutrient Management” plans have been put into effect requiring farmers to adhere to specific phosphorus-controlling tactics to assure that excessive amounts of fertilizer or animal waste, hence phosphates, do not run off into waterways. In addition, phosphorus recycling programs currently in practice work at removing and/or reducing phosphorus/phosphates in the environment.  All these measures help to reduce the amount of our overexposure to phosphates, however, higher than desirable levels of phosphates are still reported in tap water across the country.

How To Limit Phosphate Exposure

Too much phosphorus/phosphates in your diet are thought to lead to:

• Calcium leeching from bones which could lead to osteoporosis and fractures
• Kidney damage
• Heart disease and/or arterial damage
• Increased risk for skin cancer

If you are concerned that you may have too high blood levels of phosphorus, ask your doctor for a simple blood test that can give you a baseline guide. Although some sources differ in their recommendations, the Food and Nutrition Board of the National Academy’s Institute of Medicine lists a safe range for phosphorus consumption for adult men and women as 700 mg minimum to 4,000 mg maximum per day.

Here are some ways you can monitor your phosphorus/phosphate intake:

• Limit your intake of animal proteins which are naturally higher in phosphorus.
• Limit packaged breads, muffins, etc, which contain higher levels of phosphates as preservatives. Couple with the grain’s natural phosphorus content, you need to balance consumption with other foods.  For example, 8 grams of wheat bran contains 1200 mg of natural phosphorus alone!
• Find a good food phosphorus food guide to get a rough idea of how much you are eating every day.  A can of sardines contains 450 mg, 5 Brazil nuts contain 590, 25 pistachios contain 550 mg, all of which are near, or over, half the adult minimum for the day!
• Most fruits and vegetables are typically fairly low in phosphorus, so eat more of these.
• Limit your consumption of sodas, especially colas. These are high in phosphoric acids.
• Limit packaged foods that contain preservatives. Most contain some type of phosphate as a preservative.  Look for names like calcium phosphate, potassium phosphate, magnesium phosphate, dicalcium phosphate.
• Be sure you are getting enough calcium. It helps balance phosphorus.
• Limit the use of antacids and laxatives which contain a lot of phosphorus.
• Get a good water filter system that helps clear phosphate scale.

I would like to assure you, as I do my own patients, that, even if you just limited your intake of animal proteins and cola sodas alone, the risk of you having overly high phosphorus levels would be very low to none. Following some of my other recommendations above will also help ensure that you stay within safe levels to prevent possible bone, heart, arterial and kidney damage.

Stay Well,
Mark Rosenberg, M.D.

Food Data Chart, http://healthyeatingclub.com/info/books-phds/books/foodfacts/html/data/data5f.html

Phosphate Facts, http://www.phosphatesfacts.org/nutrient.asp

Is Lowering Phosphate Exposure Key To Preventing Heart Disease? http://heart.bmj.com/content/95/21/1770.abstract