Examples of parabens include butylparaben, ethylparaben, isobutylparaben, methylparaben and propylparaben. Typically a product will contain more than one paraben plus they are normally used in combination with other preservatives to target different types of microorganisms.
Parabens can be found in 90% of cosmetics: lotions, mascaras, foundations, lipsticks, deodorants, shaving gels, shampoos, conditioners and other day to day products.
Parabens are not bad for your hair as such but they are thought to be bad for the body; they have been connected to breast cancer and although studies haven’t conclusively said that parabens cause cancer, cancerous cells were found to contain parabens in a higher-than-normal density.
It is thought that parabens disrupt the function of hormones by mimicking oestrogen. Increased exposure to oestrogen is associated with a greater risk of breast cancer.
In a 2002 study parabens were found to reduce the sperm count of mice. However, the concentration of parabens was 100 times higher than that found in the average cosmetic product.
The parabens found in make-up and other cosmetics are synthetically produced but parabens do naturally occur in certain foods, e.g. blueberries Only a minute quantity of parabens enter the body through food. Having parabens in so many products means they enter the body through the bloodstream and we thus might be getting higher concentrations than is healthy.
The current official US government guideline is that parabens are safe as used in cosmetics.
Personally, given the current state of flux on whether or not parabens are harmful, I wouldn’t freak out if you find parabens in some of your products. That said, I would avoid them where possible to keep on the safe side.