Cosmetics advertised as natural and organic are a several billion-dollar beauty market, but those labels don’t mean much, experts say.

Actress Jessica Alba has benefited from the growing demand for wholesome items as her business, The Honest Company, has obtained a billion-dollar valuation. Major personal-care companies are rolling out “natural” products packaged with green letters and pictures of plants.

Shoppers can paint their nails with vegan nail polish, shine their lips with gloss made from goji berries or rouge their cheeks with mineral-based powders.

The global organic personal-care market was worth more than $8 billion in 2013, according to market research firm Grand View Research. North America generated 35 percent of the revenue share that year, analysts found. They estimate that the sector will reach $20 billion by 2020.

Natural hair dyes are now being marketed in such major retailers of organic products as Whole Foods, which sells Naturtint and Herbatint. Even CVS and Walgreens have slightly more “green” options than before, including Clairol Natural Instincts and Shea Moisture.

While these products promote ingredients such as coconut oil, olive oil and shea butter, the extent to which they are natural is debatable and loosely regulated.

We asked two chemists  to comb through a list of 25 ingredients commonly present in the four aforementioned brands to determine whether they were as natural as the packaging indicated.

What they found was that most of the ingredients listed in the dyes may be based on naturally occurring compounds but most were synthesized or heavily processed from their original form.

Michelle Francl, a chemist at Byrn Mawr College in Pennsylvania , said it would be hard to call the ingredients “natural.”

“Most of this stuff is produced in a plant,” she said.

One of the synthetic ingredients is acrylates copolymer. It can be used as a binder in skin and hair products or as an emulsion stabilizer.

Art Rich, a cosmetic chemist, said only a few ingredients are actually part of the dyeing process. That’s the case for many skin and hair-care products. “An acne cream has many ingredients, but only two work on the acne,” he said.

All four dyes had at least one synthetic material, and all four shared the same one: etidronic acid.

Etidronic acid allows products to remain intact in water. It’s also used in many soaps and shampoos.

Francl said the naturalness and safety of nearly every ingredient boils down to molecular chemistry. “To a chemist, it’s about structure,” she said. “The structure of a molecule determines what it does and how dangerous it is.”

Karla Siereveld is the Clairol Research & Development principal researcher. She said the Natural Instincts line was developed as a healthier alternative to other hair dyes offered by the company. The company has added naturally occurring oils and has removed ammonia from the formula.

International Trade Routes of New York distributes Naturtint. Brenda Boice, president of the company, said Naturtint had to reformulate some of its ingredients to comply with California’s Proposition 65 and the strict ingredients standards for Whole Foods. Proposition 65 requires California to state the chemicals known to cause cancer or birth defects or other reproductive harm in each product.

“Naturtint is not 100 percent natural but is a great alternative to conventional hair color brands,” she said.

It’s difficult to determine how natural a product is because the FDA doesn’t have an operating definition of “natural” for labeling cosmetics and because the USDA regulates the term “organic” only as it applies to agricultural products.

A product can, however, be certified under the USDA’s National Organic Program by an accredited agent. After certification, the product can be labeled with one of four categories: 100 percent organic, organic, made with organic ingredients and less than 70 percent organic.

However, Francl and Sierveld pointed out that it’s difficult to have a hair dye that’s all-natural.

“To deposit color onto the hair, you have to have peroxide, and you’ll also have to have an alkalizer,” Sierveld said. “You have to have those two ingredients, which are very far from being natural.”

Francl said that  if people want to color their hair in the most natural way possible, they should use henna, mineral powders or lemon juice along with sun exposure.

“To take the color out of your hair and put new color or to cover up the color is a nasty chemical process,” she said.

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