Contributing writer By Korin Miller | Medical review by Keira Barr, M.D.
Last updated on August 26, 2021

Collagen is a crucial element of your skin. This protein is responsible for giving your face that youthful bounce, and as it declines, fine lines appear. "Collagen literally holds us together—it makes up 30% of the body's protein and 70% of the skin's protein," functional medicine practitioner Robert Rountree, M.D., tells us. "The No. 1 cause of skin aging is the loss of collagen." So how does it decline? There are a few reasons—some are in your control and others aren't.

Below are the factors that reduce your collagen levels, plus what you can do to support them naturally:

 

1. UV exposure

There's a proven link between UV exposure (sunshine over time) and loss of collagen. One study observed collagen under UV light and found that there was a "significant decrease" in collagen structure afterward. UV rays negatively impact collagen through "various mechanisms," board-certified dermatologist Gary Goldenberg, M.D., assistant clinical professor of dermatology at the Icahn School of Medicine at Mount Sinai in New York. says—including DNA changes to the cells that make collagen as well as the production of free radicals that can affect collagen directly via oxidative stress.

 

2. Age

Collagen production starts to dip in most people's bodies from the time they're in their late teens or early 20s and decreases about 1% a year. However, the exact age that this process starts is different for everyone, says Goldenberg. This collagen attenuation picks up pace during and after menopause.

Regardless, the process is inevitable and, unfortunately, outside of your control. "Our bodies always balance collagen production and degradation," Goldenberg explains. "When we are young, our bodies produce more collagen than we break down. That balance tips the wrong way with age since tissue regeneration decreases." 

 

3. Smoking 

You've likely heard by now that smoking is, uh, not good for you and causes premature aging. Well the main reason it does so is because it directly and negatively affects collagen. In fact, smoking is the "big one" for collagen damage, Goldenberg says. "Smoking decreases the amount of oxygen delivered to tissues. Therefore, tissue cannot regenerate and is more likely to become damaged and die," he explains. And that plus the oxidative stress of chemicals in tobacco smoke can lead to premature wrinkles. One study on twins found that those who smoked had more wrinkles, crow's feet, and facial lines than their non-smoking counterparts.