Even though citric acid is a common food preservative, it’s also in everything from our household cleaners to our skincare products.
But some people may see the word “acid” and immediately become concerned about the risks associated with putting this mysterious ingredient into their body. So, should you be worried about consuming or using products that contain citric acid?
The simple answer is: no. But the reason why is slightly more complex than that.
What Is Citric Acid?
Citric acid is a weak organic compound and arguably the most common food additive for processed foods. The ingredient is added to foods for a couple of reasons.
First of all, it is a natural food preservative, but it is also used to enhance flavoring. Adding this ingredient yields an acidic or slightly sour taste to foods and drinks.
Citric acid is also frequently used as a cleaning agent, and because it is biodegradable and made from raw, natural materials, it is an environmentally-friendly one. It’s more sustainable than ingredients like sodium lauryl sulfate (SLS) that are derived from petroleum or palm oil (at the cost of the rainforests.)
When isolated, citric acid looks like a white crystalline powder, but it is naturally present in many forms of life. It comes in an anhydrous (water-free) form that crystallizes from hot water, or as a monohydrate that is produced using cold water. This acid can be found in most plants, as well as in many animal tissues and fluids as part of the metabolic function.
The Two Types of Citric Acid
There are two primary methods of citric acid production: naturally derived and non-naturally occurring.
This type comes from fruits and vegetables, particularly citrus fruits.
When you hear the term citric acid, you may think immediately of citrus fruits. Although citric acid is present in various foods, there is certainly a higher concentration in citrus fruits, like lemons and limes. The substance accounts for 8% of their dry weight and ultimately determines the pH level of fruit juices (such as lemon juice).
This chemical, citric acid, was first isolated in 1784 by a Swedish chemist, who crystallized it from lemon juice. After the discovery, citric acid derived from Italian lemons was used to preserve American foods — which worked well until those imports were disrupted during World War I. Then, a new, less natural method began to be implemented.
Scientists create this form by feeding sugars to mold.
In 1893 chemists discovered that penicillium mold could produce citric acid when fed sugar, but this information was not utilized for production until WWI disrupted lemon imports from Italy. After this shortage, American chemists referred back to their discovery and started making citric acid solutions from molds.
These chemists manufactured citric acid through the fermentation of sugar or molasses in the presence of a fungus. Today, sucrose or glucose, often made from corn starch, is fed to fungus, most commonly a type of black mold called aspergillus niger (A. niger).
Although any kind of mold certainly sounds frightening, this is not the same black mold known to cause serious health risks. Aspergillus niger is a particular strain that is not as lethal as other molds. People with impaired immune function, however, should take precautions.
Is Citric Acid Safe to Consume?
Even though citric acid can still be obtained from lemon or pineapple juice, the acid created from mold is cheaper for industrial production purposes. After the mold is fermented with sugars, the mold is filtered out, and the isolated acid remains.
Some people have raised concerns that this acid could cause tooth enamel to decay. Nonetheless, research shows that, at least on its own, it does not cause damage to your teeth. Still, consuming sugary drinks and candies that contain this acidic ingredient could still lead to cavities and other dental issues.
The U.S. Food and Drug Administration (FDA) deems non-naturally occurring citric acid as “generally recognized as safe.” In addition to that designation, it is also recognized as safe for use in food by all other major national and international agencies tasked with food regulations.
While consuming products derived from a mold certainly sounds scary and bad, research overwhelmingly shows that citric acid is not bad for you and safe for most people. In fact, it has many health benefits that may surprise you.
What Are the Health Benefits?
When you consume citric acid, you may receive the following health benefits:
- Metabolizes energy: Citrate, which is a molecule related to citric acid, can provide humans with energy. This molecule is formed during the citric acid cycle, also known as the tricarboxylic acid (TCA) or Krebs cycle, which entails a series of chemical reactions that help transform food into usable energy.
- Nutrient absorption: Research suggests that this substance improves the bioavailability of minerals, improving the body’s ability to absorb nutrients.
- Antioxidant: It acts as an antioxidant, and protects the liver from damaging free radicals.
- Alkalizing agent: It can be used to restabilize an acidic environment, often caused by stress or poor nutrition.
- Kidney stone prevention: Its alkalizing powers serve to prevent certain types of kidney stones caused by high-acidity urine.
- Disinfectant: It kills some types of bacteria and viruses.
What Products Contain Citric Acid?
In 2007, 50% of citric acid produced went into beverages, 20% was used for food preservation or flavoring, 20% was used for cleaning products, and the remaining 10% was used in cosmetics and pharmaceuticals.
Food and Drink
Citric acid is used in virtually all processed foods. It adds flavor to soft drinks and stabilizes canned and jarred fruits, vegetables and meat products. Calcium citrate, which is the calcium salt of citric acid, is commonly used to prevent botulism and keep food fresh over long periods of time.
Here’s a brief overview of some of the other foods and beverages where you can find this additive listed as an ingredient:
- Ice cream, caramel, candies and other sweets
- Cider, beer and wine
- Certain cheeses
- Baked goods and cake mixes
- Frozen foods
- Pre-cut fruits and vegetables such as apple slices (It keeps them from turning brown.)
- Baby food
Citric acid is particularly effective at cleaning chrome and other metals, so it is used in a variety of cleaning products. It produces foam and works efficiently in hard water without the use of a water softener — and also helps control the pH levels of these cleaning supplies.
This ability to eat away at hard water buildup makes this chemical a great dishwasher detergent. It’s also commonly added to cleaners for its ability to remove stains and odors, and it is used in disinfectants that kill certain types of bacteria and viruses.
Sometimes, citric acid is mixed with other ingredients to make alpha-hydroxy acid, which is used for skin smoothing. It is used as a preservative in other cosmetics and toiletries to make them last longer. You can find this acid in a variety of beauty products, including bath bombs and other personal care products.
Because it alkalizes high-acidity urine, citric acid can play a role in treating health issues such as kidney stones. The substance is also included in creams for skin infections or combined with sodium citrate to treat metabolic acidosis, a condition that occurs in some people with kidney problems.
However, you should always consult a medical professional before taking it medicinally. Overconsumption has — ironically — been known to actually cause metabolic acidosis.
What if You Have a Citrus Allergy?
So, if you have a citrus allergy, do you need to avoid citric acid?
No, because it does not promote an immune response, which is a requirement when classifying an allergy.
If someone appears to be allergic to citric acid, they are actually allergic to the trace amounts of corn (from glucose) or mold present in the acid. Though the mold is generally recognized as safe, spore inhalation can pose health risks for people with weak or impaired immune systems.
It’s Probably Safe, Even When It’s Not Natural
In short, although some experts worry about artificially-made citric acid, there have been no definitive studies that show it poses any health risks. If you’re worried, however, stick to products that only contain naturally derived citric acid.
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