Is Trisodium Phosphate As a Food Additive Safe to Eat?

Although it's a common ingredient in many of our favorite packaged foods, trisodium phosphate isn't well-known by many people. While the ingredient is safe to consume in small quantities, trisodium phosphate can be problematic for the kidneys if eaten in large amounts.

Before your next trip to the grocery store, consider the foods containing large amounts of the ingredient and adjust your list accordingly!

Read more: 20 Scary-Sounding Food Additives That Are Actually Harmless

Phosphorus exists in both organic and non-organic forms, according to a 2016 study published in the Journal of Renal Nutrition. Organic phosphorus is a naturally occurring mineral found in foods such as meats, fish and nuts. Inorganic phosphorus is typically found in food additives (aka phosphates) such as trisodium phosphate.

Trisodium phosphate is also used in inedible products like paint and cosmetics; however, it's not the same type of trisodium phosphate that's seen on some packaged foods' ingredient lists. The amount of trisodium phosphate used in food is safe for ingestion and is food-grade quality, according to the University of California Berkeley. Plus, the U.S. Food and Drug Administration (FDA) classifies it as a Generally Recognized As Safe (GRAS) additive.

As a food additive, trisodium phosphate serves several purposes including enhancing flavor and preventing caking, among others, according to the University of California Berkeley. The additive is commonly present in processed cheeses, cereals and cereal bars. Fast food, in particular, contains high levels of trisodium phosphate. Sodium phosphates, like trisodium phosphate, are often added to raw poultry, beef, pork and seafood products to improve tenderness in leaner cuts of meat.

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Trisodium phosphate can be dangerous if consumed in its raw form — which, unless you work with the compound in a laboratory, probably isn't likely to happen to you. Inhalation or ingestion of trisodium phosphate can lead to coughing, sore throat, abdominal pain or even shock, according to the International Programme on Chemical Safety. If you work in a lab or other setting that involves handling the compound, wear protective clothing and handle with care.

While trisodium phosphate is classified as a GRAS food additive by the FDA, there are some concerns worth considering. In general, inorganic phosphate food additives (such as trisodium phosphate) are very well absorbed in the body and can lead to elevated blood levels, according to the University of California Berkeley. In fact, the 2016 Journal of Renal Nutrition study found that the body absorbs only 40 to 60 percent of organic phosphorous and more than 90 percent of inorganic phosphorous.

High levels of phosphorus can cause the body to pull calcium from the bones, which weakens them, according to the National Kidney Foundation. Elevated levels can also cause dangerous calcium deposits in your lungs, eyes and heart, leading to increased risk of heart attack and stroke, according to the National Kidney Foundation. For those with normally functioning kidneys, the organs easily remove extra phosphorus in the blood. However, for patients with chronic kidney disease, the kidneys may struggle to filter phosphorus from the bloodstream.

There are measures you can take to control the levels of inorganic phosphates you consume. As your initial step, you may want to cut back on processed foods, recommends the Center for Science in the Public Interest (CSPI). Baked goods, cereals, sodas and processed meats all contain high levels of phosphates.

Dairy products often contain higher levels of phosphorous additives too, according to the Mayo Clinic. Replace your milk, pudding, yogurt and processed cheeses with lower phosphorous alternatives like almond or rice milk products.

Read the labels of your food products carefully, advises the Mayo Clinic. While not all foods contain trisodium phosphate specifically, they may contain other similar additives that affect your body in the same way. Keep an eye out for ingredients that contain "phos" (like calcium phosphate or phosphoric acid) in the title.