If you ever sunk your teeth into a lemon, you've tasted citric acid. All citrus fruits have it. Manufacturers add a manmade version of it to processed foods. Medicines with citric acid in them treat health issues like kidney stones.
Where You Find It
It's not just sour citrus fruits that have citric acid. All plants and animals hold within them small traces of it.
You can also find citric acid in:
Packaged foods and drinks. Citric acid helps keep canned and jarred foods fresh over long periods of time. It can prevent some kinds of fresh-cut produce, like sliced apples, from turning brown.
Citric acid can also help thicken foods or give them a slightly sour flavor. That's why you might see citric acid listed as an ingredient in some ice creams, sorbets, or sodas.
Wine. Citric acid can balance out the acid in a food or drink. Winemakers sometimes add it to their products to improve the taste.
Medicines. Some creams include citric acid to help clear up skin infections. Other citric acid drugs that you take by mouth can reduce the amount of acid in your urine. This can help prevent kidney stones. You might also take citric acid for metabolic acidosis, a buildup of acid inside your body.
Personal care products. When manufacturers mix citric acid with other ingredients, they can form a compound called "alpha-hydroxy acid" that helps smooth your skin. It's also in some cosmetics and toiletries, like lipstick, hair spray, and deodorant, to help them last longer.
Household cleaners. Because citric acid can eat away at hard water buildup, you'll often see it in dishwasher detergent. Other household cleaners also include it as an ingredient since it can help remove stains and odors.
Disinfectants. Since citric acid kills some types of bacteria and viruses, you'll find it in insect sprays, products that kill fungus or algae, hand sanitizer, and even some tissues you use to blow your nose.
Environmental cleanup products. Citric acid can safely remove toxins from polluted soil and even clean up nuclear waste.
The FDA says citric acid is "generally recognized as safe" in food and skin products. Still, some experts think that more research is needed.
Citric acid may cause:
Skin irritation. When it touches your skin for long periods of time, it can cause stinging, swelling, or hives.
Tooth problems. Drinks and candies that contain citric acid can wear away the enamel (the outer layer) of your teeth. This can make your teeth more sensitive, turn them yellow, and make it more likely you'll get cavities.
Sometimes, drugs with citric acid can cause severe side effects, such as:
- Chest pain
- Fast heartbeat
- Tingling or numbness in your hands or feet
If you notice any of these symptoms, contact your doctor right away.