Rare is the woman who can indulge with abandon at dessert and not wonder where a little extra wobble might show up later. We all know that when it comes to our bodies, sugar is a sly villain—falling prey to its siren song (presumably something like an Oompa Loompa ditty) will give our taste buds a hit of pleasure before wreaking havoc everywhere else. But there probably aren’t many of us who worry that eating it might also cause wrinkles—and that’s not a sweet story either.
The science is this: When you have sugar molecules in your system, they bombard the body’s cells like a meteor shower—glomming onto fats and proteins in a process known as glycation. This forms advanced glycation end products (commonly shortened, appropriately, to AGEs), which cause protein fibers to become stiff and malformed. Much of what is known about glycation’s ill effects comes from diabetes research: The connective-tissue damage and chronic inflammation resulting from diabetics’ sustained high blood sugar can lead to debilitating conditions, such as cataracts, Alzheimer’s, vascular tightening, and diseases of the pancreas and liver.
The proteins in skin most prone to glycation are the same ones that make a youthful complexion so plump and springy—collagen and elastin. When those proteins hook up with renegade sugars, they become discolored, weak, and less supple; this shows up on the skin’s surface as wrinkles, sagginess, and a loss of radiance. The presence of AGEs also makes the complexion more vulnerable to bad-news assailants such as UV light and cigarette smoke. As New York–based dermatologist Cheryl Karcher, MD, puts it: “Number one, the glucose makes the cells abnormal; and number two, it creates free radicals. So you get a double whammy when it comes to aging.”
To an extent, glycation is a fact of life. It’s happening right now, to all of us. It can even be measured: The cross-links formed between sugars and proteins emit a fluorescence, which scientists can capture using Visia complexion-analysis cameras. “If you take a fluorescent image of children, their faces will come out very dark,” says Procter & Gamble biochemist Greg Hillebrand, PhD, “but with each decade, the AGEs, and therefore the brightness, will accumulate more and more.” This means that by the time we reach our dotage, we can expect our Visia visages to resemble those of the incandescent aliens in Cocoon. The external signs of glycation show up around the age of 30 or 35, when a perfect storm of built-up sun damage, environmental oxidative stress, hormonal changes, and the development of AGEs begins to result in, well, a-g-e. “When you’re younger, your body has more resources to ward off damage, and you’re producing more collagen,” says New York– and Miami-based dermatologist Fredric Brandt, MD, who in 2007 was one of the first to launch an anti-aging skin-care line specifically addressing glycation. “When you reach a certain age, these sugar by-products begin to build up at the same time that your threshold for damage is getting lower.”
Lest you rue the day you first tasted a Krispy Kreme, note: Refined sugar isn’t the only culprit. Health-nut staples such as whole grains, fruits, and vegetables turn to glucose when digested too—albeit in less damaging fashion. And even if we could completely eliminate all types of sugar from our diets, we shouldn’t: It’s an essential fuel for cells and energy metabolism, critical to survival. “For most people with normal levels of glucose, the glycation process is something that happens gradually over the course of a lifetime, and it’s really not that big of a deal,” Hillebrand says, “but diet and lifestyle choices can affect how quickly the effects can be seen on the skin.” One of the key hallmarks of glycation, Hillebrand explains, is the yellowing of skin often seen prematurely in smokers. “Smoke reduces antioxidants in skin, and smokers’ vitamin C and E are being used up trying to take care of all this oxidation that’s caused by smoking, so they don’t have a lot of antioxidant potential to take care of normal processes like glycation,” he says. “And if you add a high-glycemic-index diet, you’re just asking for trouble.”
While glycation can’t be completely stopped, it can be slowed (though Hillebrand says there are pharmaceutical companies working on “AGE busters” that could break the cross-links once they’ve already formed—”something that would apply to a number of diseases as well as skin aging”). From a dietary standpoint, forswearing white sugar, high-fructose corn syrup—which studies have shown increases the rate of glycation by 10 times, compared with glucose—and simple carbs is a no-brainer. “Even though all carbs get converted into sugar, when you eat the good ones, like brown rice and whole-grain bread, you get less glucose, and you get it more slowly,” Karcher says. Brandt also recommends taking supplemental carnosine, an amino acid that has been shown to protect against AGE buildup.
Skin care too makes a difference. Scientists have been on the hunt for potent antiglycation agents since the ’80s, when biochemist Anthony Cerami, PhD, found that aminoguanidine molecules block glucose-collagen pairs from forming, but products containing viable AGE fighters only began to appear on the market about five years ago with the introduction of Brandt’s Lineless range. Now that glycation is widely recognized as a major cause of aging, lots of comprehensive anti-aging creams contain AGE fighters too. Superstar multitasker green tea has been proven to significantly interfere with the glycation process while stimulating collagen synthesis—so if you’re using a product containing green tea (or drinking it regularly), you’re already protecting your skin. “Anything that stimulates the fibroblasts to build new collagen is going to help eradicate damage,” Brandt says, noting that retinoids and some dermal fillers fall into this category. “Since your body has a process where old collagen is broken down by enzymes and new collagen is generated, what’s going to happen is that the old glycated collagen will eventually be eliminated and replaced by un-glycated collagen.”