Parahydroxybenzoates, or parabens, are man-made chemicals that prevent mold and bacteria growth. They are used to preserve cosmetics, medicines, foods, drinks, and personal care items. This makes them last longer. 

The use of parabens became quite controversial after being found in the cells of breast cancers patients. Early research showed parabens affect hormone function. 

This can cause changes in cholesterol, blood sugar, thyroid, and immune function. The risk of allergies, obesity, and infertility has also been associated with the use of parabens.

Read on to learn more about the different types of parabens, their potential to affect your health, and where you can find them. Keep in mind that paraben research has been limited to animal and cell studies. Further research is needed on the effects of parabens on humans to confirm the long-term effects of use.

Negative Health Effects of Parabens

The US Food and Drug Administration (FDA) and the Cosmetic Ingredient Review (CIR) tests ingredients in food and cosmetics for safety. Neither organization found any risks with the use of parabens.

The FDA said the use of up to 0.1% of methyl- and propylparabens was safe for food and drinks. Cosmetics usually contain between 0.01% and 0.3% parabens. According to the CIR, these compounds are safe in doses of up to 25%.

Other research says parabens are endocrine-disrupting chemicals (EDCs) that cause problems to the endocrine system. EDCs attach to cells in the body, which results in blocking or weakening hormone cell communication.

Changes in Hormone Function

Parabens cause changes in hormone function, which can result in the following:

  • Changes in brain functionChanges in cholesterolHigh blood sugar Changes in thyroid hormonesPoor immune functionSensitivities, allergies, and rashesFertility issuesObesity riskRisk of cancer

Changes in Brain Function

Some parabens may harm the brain. Others may help it.

One study found that butyl- and isobutyl-parabens prevented learning in animals. The same animals also experienced low levels of antioxidants, more inflammation, and anxiety.

However, propylparaben was found to reduce the effects of traumatic brain injury associated with Alzheimer’s disease.

Changes in Cholesterol

Cholesterol is needed to make estrogen and testosterone. Parabens can stop these essential hormones from being made.

A connection between triglycerides and the levels of methyl-, ethyl-, and propylparabens was also seen in humans. Triglyceride levels varied by age, sex, weight, and ethnicity. 

Animal research shows parabens can turn on the genes that make triglycerides, a type of fat found in the blood. Too many triglycerides in the blood can contribute to the development of heart issues.

Those with high triglycerides were older, obese, and/or male. Women, non-Hispanic Whites, and non-Hispanic Blacks with paraben exposure had lower triglyceride levels. Canadian men exposed to propylparaben also had a risk of developing high cholesterol. Women exposed to methyl-, propyl-, and ethylparaben had increased levels of good cholesterol, HDL.

High Blood Sugar

A mixture of parabens seems to do more harm than one paraben alone. A combination of butyl- and propylparabens increased the blood sugar for pregnant women in their first and second trimesters. This puts them at risk for gestational diabetes. 

Less is known about the effects of parabens in non-pregnant individuals. One study found no significant changes in those exposed to parabens.

Similar effects could occur in men and non-pregnant women. More research is needed to understand how parabens affect blood sugar overall.

Poor Immune Function

Good immune function is tied to a healthy gut. Using antimicrobial parabens prevents the growth of healthy bacteria. This can weaken the immune system.

Parabens cause the production of Type 2 helper T (Th2) cells. Th2 cells make the immune system very sensitive., causing it to overreact to stimuli more than normal.  Th2 cells are also found in those with asthma and eczema. 

Parabens can weaken immune defenses. The presence of methylparabens was associated with fewer Th1 cells, which prevent autoimmune responses. This will protect the body from attacking its own cells.

Sensitivities, Allergies, and Skin Rashes

The skin has its own microbiome. Parabens can reduce the number of healthy bacteria on the skin, weakening the skin’s immune system.  

Allergies and sensitivities can develop, and some people may experience a histamine response. Symptoms include red, itchy, and dry skin. Skin rashes can occur anywhere on the body, including the scalp. Scalp rashes will dry out the hair and may even cause hair loss. 

Methylparaben is a small paraben that is unlikely to cause allergies and sensitivities. Butylparaben is a medium-sized molecule that is bigger than methylparabe, but smaller than large parabens. It also has a weaker response than large molecules like heptylparaben.

Parabens with large chemical structures have a greater histamine response. More histamine means worse allergic reactions.

Medications with parabens placed on broken or damaged skin may also cause skin reactions. Parabens in food can also cause reactions but are rare.

Other Risks

Other identified risks of paraben exposure include:

  • Risk of cancer: Parabens can activate the hormone estrogen. High levels of estrogen have been found in breast cancer tumors. Breast cancer is also associated with the continual use of paraben-containing personal care products applied near the breast area.
  • Fertility issues: Parabens can lower testosterone and sperm production. However, research is limited to animals and failed to prove toxicity in females with paraben-related uterine growths.
  • Changes in thyroid hormones: Females with high levels of butylparaben experienced lower levels of the thyroid hormones thyroxine (T4) and triiodothyronine (T3). These changes could cause thyroid dysfunction.
  • Obesity risk: Methyl- and propylparabens were found in women with higher BMIs. Food and dietary supplements with high levels of parabens may be responsible for weight gain.

Who Is at Risk for Paraben Exposure?

Parabens are absorbed when we eat foods and drinks containing these substances. The skin also takes in paraben when products with these chemicals are applied to the face and body. Parabens have also been found in the sediment, sewage, water treatment plants, rivers, soil, and house dust.

Parabens are all around us so everyone may have some exposure. Especially if you consume foods and drinks and/or use certain paraben-containing products.

Higher Levels of Parabens Have Been Found in Certain Individuals

The National Health and Nutrition Examination (NHANES) survey found about 33% of the 9,813 individuals tested had a presence of parabens at or above the limit of detection in their urine. 

Types of Parabens

Parabens are made from para-hydroxybenzoic acid (PHBA). PHBA is an acid found in bacteria, plants, and fruits.

Individuals With the Highest Paraben Exposure

The latest National Health and Nutrition Examination (NHANES) survey showed the following:

Parabens are made from an acid-base chemical reaction called esterification. When PHBA and alcohol are combined they create an ester. Esters vary by the number of chemical bonds in the molecule. The type of alcohol used will determine the number of esters.

  • Methylparaben (methanol)Ethylparaben (ethanol)Isopropylparaben (isopropanol)Propylparaben (n-propanol)Butylparaben (butanol) Isobutylparaben (isobutanol)Pentylparaben (pentanol)Heptylparaben (heptanol)Benzylparaben (benzyl alcohol)Pentylparaben (pentyl alcohol)

The more ester bonds the more active the paraben. So medium, long, and/or branched-chain esters are more harmful. 

Methyl- and ethylparabens are short-chain parabens. They have weaker estrogenic effects than medium-chain esters like propylparaben. Long-chain esters like butylparaben are stronger than medium-chain esters. The order of increasing estrogenic activity is as follows:

  • MethylEthylProplyButylIsobutyl

Long-chain esters are the most harmful according to test-tube studies.

Another thing that determines a paraben’s harm is if it dissolves in fat. Cell studies found parabens like benzylparaben easily bound to estrogen. This is a hydrophobic, long-chain ester.

More research needs to be done to know if these effects can be replicated in humans.

Products With Parabens

Parabens are often found in cosmetics, personal care products (PCP), pharmaceuticals, medicines, and foods. Here is a list of parabens broken out by category.

How Do Parabens Differ?

There are nine different types of parabens. Methylparaben, ethylparaben, propylparaben, and butylparaben are the most common.

Cosmetics and Personal Care Products

The main source of paraben exposure comes from cosmetics and personal care products.  

  • Face, body, and hand creams
  • Eye shadow
  • Foundation
  • Blush
  • Eyeliner
  • Mascara
  • Lip gloss, lipstick, lip balm
  • Lotions/Moisturizers
  • Mud packs
  • Skin lighteners
  • Body wash/scrubs
  • Shampoo/Conditioner
  • Shower gel
  • Shaving gel
  • Haircare products
  • Perfume
  • Skin toner
  • Deodorant
  • Nail polish
  • Sunscreen
  • Facial cleanser or soap
  • Makeup remover wipes
  • Baby products

Personal care products often contain methyl-, ethyl-, butyl-, and propylparaben.

Medications and Pharmaceuticals

The concentration of parabens in medications and pharmaceuticals is around 1%. See below for what products fall into this category:

  • Pills
  • Suppositories
  • Pain relievers
  • Eyewashes
  • Acne medication
  • Medical weight gainers
  • Injectable drugs
  • Condoms and other contraceptives

Foods

Regardless of the type of food packaging (paper, glass, plastic, or can), methyl-,  ethyl-, and propylparbens have been seen in 90% of foods. Butyl- and benzylparabens were also found but less frequently. Here is a list of foods that contain parabens:

Beverages

  • Bottled waterCarbonated soft drinksAlcoholic beverages (beer, wine, bourbon)JuiceMilkInfant formulaCoffee

Dairy Products

  • YogurtCheeseIce cream

Fats and Oils

  • Vegetable oilSalad oilOlive oil

Fish and shellfish

  • Freshwater fishMarine fishShrimpCrabClam

Grains

  • Wheat flourBreadRiceNoodlesPie/pastriesPastaPizzaCorn productsCookiesCakesCereals

Meats

  • BeefPorkChickenTurkeyHamSausage

Fruits

  • ApplesPearsPineapplesPeachesGrapes/raisinsOranges BananasYellow melonsPassion fruitMixed fruits

Vegetables

  • BroccoliCabbageCarrotsCeleryCucumbersMushroomsOnionPotatoesTomatoesGreen peppersRadishesPumpkinLettuceBeans Mixed vegetables

Animal feeds can also contribute to the level of parabens in meats and other animal products.

Other Foods that Contain Parabens

  • Jams/jelliesPicklesSaucesDessertsFlavoring syrupsProcessed foods (fish, meat, fruits, and vegetables)CondimentsBean productsOlivesVanilla extractIcings

Summary

Methyl-, ethyl-, butyl-, and propylparaben are the types of parabens in shampoo, food, and other personal care products.

These parabens do not bind to cell receptors as strong as the actual hormone estrogen. Research shows they are fine in low doses. However, intake may exceed safe levels when numerous paraben-containing products are used on a daily basis.

While the research is limited to animal and cell studies, there’s the potential that parabens can cause health problems. Until controlled human studies are carried out it is hard to know the true effects of long-term paraben use. 

In the meantime, you can limit your exposure to parabens cutting back on the use of paraben-containing products.

A Word From Verywell

Animal and cell research shows parabens can act like estrogen which may cause health problems. Unfortunately, there is still a lot we do not know about how these chemicals affect humans. If you have a reaction and think it may be from paraben exposure, be sure to contact your healthcare provider. They can help you get tested to see if you have a paraben sensitivity or allergy.

How To Spot Parabens in Your Products

The way to find parabens in your products is to check out the ingredient label. Some names include ethyl-, propyl-, and butyl-, isopropyl- and isobutylparaben. Anything with the word “paraben” will tell if there are parabens present.

Frequently Asked Questions

  • Are there paraben alternatives on the market?
  • Alternatives to parabens include the following:FormaldehydeQuarternium-15Im-idazolidinyl ureaDiazolidinyl ureaDimethyloldimethyl hydantoinThymolCinnamaldehydeAllyl isothiocyanateCitric acidAscorbic acidRosemary extractFormic acidPropionic acidSorbic acidBenzoic acidSalicylic acidBenzyl alcohol2-phenoxyethanolSodium benzoateTriclosanBronpolDMDM hydantoinMethylisothiazolinoneMethylchloroisothiazolinoneEssential oils (grape seed extract)These natural preservatives may also cause problems. They have been associated with allergies and other health issues. Formaldehyde has even been linked to cancer. Some may also interfere with medications so be sure to ask your doctor before using any of these products. Overall there is not enough research to prove any of these are actually safe and effective alternatives to parabens.
  • What are the environmental effects of parabens?
  • Many paraben products are used in the shower or rinsed off with water. This causes them to go down the drain and get into the water supply.Treatment plants work to eliminate parabens from wastewater but only 80% of methyl-, ethyl-, propyl-, and butylparaben are removed.Parabens pose problems for wildlife. Plankton, algae, dolphins, and polar bears were found to have high levels of these chemicals. The mixture of methyl-, ethyl-, propyl-, and/or butylparaben is more toxic than one paraben alone.
  • Why are parabens so bad for your hair?
  • Parabens may trigger the immune response which can lead to red, dry, itchy skin. Chances are if you get a rash on your body you may end up with one on your scalp. Paraben shampoo use may leave you with dry, damaged hair and possibly hair loss.Sulfates, sodium laurel, or laureth sulfate (SLS) is another chemical that causes dry skin. This substance is likely to cause scalp problems similar to parabens. So if you want to prevent potential scalp damage be sure to get a shampoo without parabens and sulfates.

Alternatives to parabens include the following:

Many paraben products are used in the shower or rinsed off with water. This causes them to go down the drain and get into the water supply.

Parabens may trigger the immune response which can lead to red, dry, itchy skin. Chances are if you get a rash on your body you may end up with one on your scalp. Paraben shampoo use may leave you with dry, damaged hair and possibly hair loss.