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Phosphoric Acid: The Dangerous Hidden Additive You’ve Likely Consumed


Phosphoric acid - Dr. Axe

Have you ever ingested phosphoric acid? Most likely, yes. Phosphoric acid is used as a rust inhibitor, a dental and industrial etchant, fertilizer feedstock, and as an ingredient in home cleaning products. So wait, why on earth would I think it’s likely you’ve consumed such a thing? Because phosphoric acid is also commonly added to soda and other processed foods and beverages to give them a more tangy flavor.

What is phosphoric acid? It’s a clear, odorless substance commonly added to colas in particular. It makes the flavor more intense and also slows down the growth of bacteria and molds that would otherwise grow rapidly in the sugar-rich beverage.

You might already know that soda and diet soda have a lot of negative health consequences, but you might not be aware of the common yet extremely health-hazardous ingredient known in the chemical world as H3P04. For starters, ingestion of phosphoric acid can cause diarrhea, stomach cramps, nausea and vomiting. (1) Let’s look at just how dangerous phosphoric acid is to human health.

What Is Phosphoric Acid?

Phosphoric acid is a colorless and odorless inorganic mineral acid. Its chemical formula is H3PO4. It’s also called orthophosphoric acid. Phosphoric acid can be either a liquid or transparent crystalline solid that’s corrosive to metals as well as human tissue. Food and beverage manufacturers like it because it’s cheap, adds tang and acts as a preservative.

When it comes to processed foods that contain phosphoric acid, dark-colored sodas like colas typically contain more than other sodas. One container of soda can contain up to 500 milligrams of phosphoric acid. The exception is root beer, which is dark in color but typically contains very little of this acid. Why do food and beverage manufacturers even use this chemical at all? They use it to give their processed products a sharper, tangier flavor.

What foods and drinks contain phosphoric acid? This compound can be found in cola beverages, bottled and canned iced teas, bottled and canned coffee beverages, breakfast cereal bars, nondairy creamers, as well as enhanced chicken and meat products. (2) The U.S. Food and Drug Administration also allows phosphoric acid in processed cheeses and other dairy products to adjust their pH levels. (3)

Watch for these other names for phosphoric acid on ingredient labels: (4)

  • E338
  • Orthophosphoric acid
  • Phosphoric(V) acid
  • Pyrophosphoric acid
  • Triphosphoic acid
  • o-Phosphoric acid
  • Hydrogen phosphate

Without a doubt, I strongly believe and science confirms that phosphoric acid should be kept out of anything we ingest. If it can remove rust from metal, what can it do to our insides? The short answer: a lot of damage.

5 Serious Health Dangers of Phosphoric Acid

1. Lowers Bone Density

Studies have linked phosphoric acid to lower bone density in humans. One study published in the American Journal of Clinical Nutrition in 2006 hypothesized that the consumption of colas containing caffeine and phosphoric acid decreases bone mineral density (BMD). Researchers measured BMD in the spine and hips of 1,413 women and 1,125 men.

For women, they found that cola intake was associated with significantly lower BMD in the hips but not the spine. Overall, the mean BMD of those with daily cola intake was 3.7 percent lower at the femoral neck (the bridge of bone that connects the ball of your hip to the top of your femurand 5.4 percent lower at Ward’s area (a region of the neck) than of those who consumed less than one serving of cola each month. Researchers found similar results for diet cola consumption and similar yet weaker results for decaffeinated cola as well. They did not see a relationship between non-cola carbonated beverage consumption and BMD. The conclusion of the study is that cola consumption is associated with low bone mineral density, especially in women. (5)

The fact that the non-cola beverages didn’t seem to negatively affect bone density and the fact that even decaffeinated cola had a negative impact point toward phosphoric acid as the enemy of bone health.

2. Triggers Major Kidney Issues

The consumption of cola beverages rich in phosphoric acid has been linked to urinary changes, chronic kidney disease and kidney stones. Healthy kidneys rid the body of any extra phosphorus. Phosphorus is naturally found in many foods so it’s not hard for us to get enough of, but it becomes problematic when we start getting too much in our diets. The phosphoric acid found in colas and other processed foods are problematic because they can easily lead to an overload of phosphorus in our bodies. (6)

A study published in the journal Epidemiology in 2007 evaluated the dietary habits of 465 people with chronic kidney disease and 467 healthy subjects. What did researchers find? Drinking two or more colas a day, either regular or diet, was associated with twice as great a risk of developing chronic kidney disease. (7)

3. Decreases Nutrients in the Body

Most people easily meet their daily phosphorus needs through their diets, especially if they consume foods high in phosphorus. It’s actually more common to have too much phosphorus in the body rather than too little. This is why consuming things that contain “hidden phosphorus” is so problematic. Phosphoric acid is a top source of hidden phosphorus.

Getting an excess of phosphorus in your diet can decrease your body’s calcium levels. In addition, it can lead to phosphorus overload, which can impair your body’s utilization of vital nutrients like iron, magnesium and zinc. Deficiencies in any of these nutrients can lead to all kinds of other health problems.


All about phosphoric acid - Dr. Axe


4. Increases Body Acidity

In food usage, the phosphoric acid is literally used to acidify foods and beverages. Is acid bad for you? Many acids (like omega-3 fatty acids) can be healthy, but phosphoric acid is not one of them. Thanks to phosphoric acid, cola beverages are extremely acidic. In fact, according to a study by the Southern Illinois University School of Dental Medicine, the top three most acidic soft drinks available today are all colas. (8)

Do you know what the pH of Coke is? The pH of Coke products ranges from 2.5 to 4.2. The most acidic Coke product is Coke Classic with a pH of 2.5. (9) To put these numbers in perspective, 7 is a neutral pH level with 0 being the most acidic pH, which is why you should step away from cola.

5. Damages Tissue

Phosphoric acid is commonly used for rust removal so it’s not surprising that it’s dangerous to human tissue. In addition to rust removal, it’s used for metal cleaning and refining and fertilizer manufacturing. It’s also found in disinfectants and detergents. With those usages, it’s not so surprising that phosphoric acid is commonly found on lists of “strong acids” or chemicals commonly used in industry that can cause chemical burns. (10)

What is surprising is the the fact that this chemical would be put into anything coming into contact with our bodies, especially our internal bodies. As a corrosive chemical, phosphoric acid can irritate and burn the eyes and skin. It can also irritate the nose, throat and lungs leading to wheezing and coughing. (11)

According to the Centers for Disease Control and Prevention, “phosphoric acid can affect the body if it is inhaled or if it comes in contact with the eyes or skin. It can also affect the body if it is swallowed.” (12) I don’t know about you, but that doesn’t sound like an ingredient I want in anything I’m eating or drinking!

Better Substitutes for Phosphoric Acid

Since sodas, particularly colas, are the main way people consume phosphoric acid, I want to give you some much better alternatives to these health-hazardous soft drinks.

If you really need to get your fix of bubbles, opt for a naturally sparkling mineral water that gives you the carbonation without the phosphoric acid — plus you’ll get some minerals in your system as well without a sugar overload.

You can also try making my homemade switchel recipe. With inflammation-reducing ginger and apple cider vinegar, this is an easy-to-make, refreshing drink loaded with healing ingredients.

Kombucha is another awesome alternative to soda. You get the fizzy bubbles (that result from natural fermentation) along with a powerful punch of probiotics, B vitamins and enzymes. Coconut water is another much healthier alternative to soda.

Final Thoughts on Phosphoric Acid

If the sugar content of soda wasn’t reason enough to avoid this popular bubbly beverage, now you have another very good reason to steer clear — it’s called phosphoric acid. You can also find this unhealthy preservative in a number of other common ultra-processed foods and drinks so read labels carefully. Even some cheese and meat products contain phosphoric acid.

When you watch phosphoric acid easily remove the rust from metal, it makes it hard not to wonder what that same acid can do to your body. Science has demonstrated a link between phosphoric acid and decreased bone density, which is especially concerning to children still developing their bones as well as the elderly who often struggle with fragile bone health. An increased rate of chronic kidney problems is another major concern when it comes to this acid. It’s also known to decrease nutrients but increase acidity, which is a terrible disease-promoting combination.

Of all the foods and drinks that contain phosphoric acid, colas are typically the hardest for many people to give up, but there are so many healthier alternatives that truly taste great and actually promote your health rather than destroy it. I hope you’ll strongly consider completely avoiding phosphoric acid in your diet to avoid the many possible unwanted health effects.

Read Next: 10 Antinutrients to Get Out of Your Diet … and Life

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