Can a cosmetic lotion turn back time? Not yet.

A few years ago, L’Oréal introduced two new product lines that used “gene science” to "crack the code" and make your skin young again. The new products were supposed to boost the production of “youth proteins” in your skin, making it look years younger. According to L’Oreal’s ad campaign, the benefits were clinically proven.

Except they weren’t. Last week, the FTC announced that L’Oréal had settled charges that the advertising for these products, Youth Code™ and Lancôme Génifique, was deceptive and misleading.

In a statement, L’Oréal responded that these claims "have not been used for some time now" and "the safety, quality, and effectiveness of the company's products were never in question."

What did L’Oréal claim? Here are some quotes from an ad for Lancôme Génifique:

"At the very origin of your skin's youth: your genes. Genes produce specific proteins. With age, their presence diminishes. Now, boost genes' activity and stimulate the production of youth proteins."

This sounds pretty amazing - and expensive, as much as $132 per bottle for Lancôme Génifique. L’Oréal Youth Code™ makes similar claims: on of its ads asks "Imagine: what if you could grow young?" and then goes on to promise "Even though you can't grow young, we now have the knowledge to help you begin cracking the code to younger acting skin."

The FTC apparently disagrees with L’Oréal's statement that the effectiveness of these cosmetics was not in question. Here is just one claim from a L’Oréal's ad that was highlighted by the FTC:

Génifique Youth Activating Concentrate is clinically proven to produce perfectly luminous skin in 85% of women, astonishingly even skin in 82% of women, and cushiony soft skin in 91% of women, in seven days.

This claim appears in a very scientific-looking bar graph in ad for Lancôme Génifique. It must be science - it's a graph! Alas for L’Oréal, the FTC states that science doesn't support this claims and that it is "false and misleading."

When I asked what studies supported the claim that these products could activate genes, a L’Oréal spokesman pointed me to two published studies, here and here. These are indeed peer-reviewed studies in high-quality journals. However, they don't support the claims made for these skincare products. Instead, they examine which genes are activated when the outer layer of skin is stressed by tape stripping, UV radiation, and washing with detergent. Neither study provides any evidence for a lotion that could activate the same genes, nor do they show that activating those genes could restore skin to its youthful state.

Can skin cream possibly make your skin young again? Well, it's plausible. A baby's skin does behave differently from an adult's skin, and much of that difference may be due to genes being turned on or off. But today, even if we knew the identity of these "youth proteins", we don't have the technology to turn them on.

To their credit, L’Oréal does invest significantly in research, so maybe they will find a youth-restoring cream one day. But not yet.

It's easy to find dramatic claims for products that restore youthful skin. Procter and Gamble's Olay® has many webpages devoted to anti-aging products, and you can be pretty certain that none of them will make you young again either. Like L’Oréal, P&G makes claims about genes:

"That discovery [the human genome] led P&G Beauty Scientists to explore how skin-related genes respond to aging and environmental stress at the molecular level."

As a geneticist myself, I can't help liking the idea that we might somehow convince skin cells to turn on a set of genes to restore their youthful state. Perhaps one of these companies will someday develop a lotion to do this - I hope they will. But they haven't done it yet. So for now, save your money: expensive skin creams are no better than inexpensive ones.