An important new study has backed up what had been found in previous, smaller studies: Some common chemicals found in makeup, beauty products and plastic containers have been found to effect hormone levels to such an extent that they can bring on menopause earlier. Yup, your makeup and anti-agers could be aging you.

Dr. Amber Cooper, an assistant professor of obstetrics and gynecology, along with researchers from the University of Missouri-Kansas City School of Medicine and the Wadsworth Center at the State University of New York at Albany examined blood and urine for 111 different chemicals that are thought to interfere with either hormone production or distribution (oftentimes referred to as endocrine disruptors). The findings were based on data collected from 31,575 people, including 1,442 menopausal women who were 61 years old on average and who weren't using estrogen-replacement drugs. The survey controlled for age, race and ethnicity, smoking and body mass index.

Women whose bodies contained higher levels of the endocrine-disrupting chemicals reported going through menopause two to four years earlier.

According to the paper, those chemicals included "... dioxins (combustion byproducts), phytoestrogens (plant-derived estrogens), phthalates (plasticizers), polychlorinated biphenyls (PCBs, coolants), phenolic derivatives (phenols, industrial pollutants), organophosphate pesticides, surfactants, and polycyclic aromatic hydrocarbons (PAHs, combustion products)."

Chemicals and the human body

Graphic: PLOS One

"Chemicals linked to earlier menopause may lead to an early decline in ovarian function, and our results suggest we as a society should be concerned,” said Cooper.

What, exactly, is the problem with reduced ovarian function and early menopause and why should we be concerned about it? Well, it not only affects fertility, but it can also lead to other health problems, like heart issues and osteoporosis. In other studies, these same chemicals have been linked to metabolic issues and cancers.

While some of these chemicals are in our air, water, and soil — and are therefore difficult to control — others are common in beauty products (phthalates), plastic containers and household cleaners — which is both good news and bad. It's bad news because it can feel like they're ubiquitous; it's good news because once you know what to look for, you can cut down on your exposures.

There are a couple options: You can, of course, forego makeup and perfume and use only totally natural products (like olive oil or coconut oil) to cleanse and moisturize your skin, and essential oils like lavender and bergamot for scent. You can minimize your makeup use, using it only for special occasions.

Or, you can look for products that don't contain these chemicals. The good news is that there are many great companies out there that make phthalate-free products. (The chemical is often used in perfumes and in scented products and it's not on ingredient labels, so don't bother looking; it's often listed simply as "fragrance.")

You can go to Whole Foods and check out the makeup section there. The organic grocery giant has a great selection and carefully monitors its products and won't sell those that include the most harmful chemicals. Whole Foods' system isn't perfect, but it's pretty good, and if you're just making the transition, you will find plenty of options.

You can also check your existing products against the listings at the Cosmetics Safety Database, which is a useful resource. Also check out the excellent site, Green Beauty Team's 101 page, which will get you up to speed on the issue quickly.

Keeping as much plastic out of your life as possible is also a great way to minimize your exposures: Don't store food in plastic containers (use glass instead) and definitely don't heat food in plastic containers or food that has plastic wrap on it. Don't drink from plastic containers (this will keep you away from the least-healthy beverages too), and carry your own metal — or better yet, glass — water bottle with filtered water from home. Don't let your pedicurist or massage therapist wrap any of your body parts in plastic — and this all goes for the kids in your life too. Phthalates have been linked to obesity, ADHD, abnormal genital development and high blood pressure in children.

Starre Vartan ( @ecochickie ) covers conscious consumption, health and science as she travels the world exploring new cultures and ideas.

Why you might want to switch (or ditch) your makeup
In an unfair twist, the very products that are supposed to make you more youthful might be aging you.