Is the Cause of Stretch Marks Just Stretching?
Stretch Marks Info
The consensus is heading toward no.
Researchers know that a stretch mark isn’t easy to explain. It’s not like the obvious whys and wherefores of scarring from a cut or a burn. They suspect that the cause must be much more complex than skin pulled too far and too fast.
Questions have arisen, such as: why do the women in some families get worse stretch marks from pregnancy than the women in certain other families? Why do the weight-lifters in the families where the women get very marked up get more stretch marks than the weight-lifters in the other families? There must be a genetic factor. And: why is it when topical hormonal creams are liberally applied over time, stretch marks mysteriously form there? Accordingly, why do the people with Cushing’s disease, a disorder involving the same hormone group that’s in the steroid creams, also develop stretch marks? That’s an indication of something hormonal behind the appearance of the scars.
Thus far, nothing is conclusive. With regard to genetic inclination, no gene has been isolated that weakens the essential components of the skin. Eventually, however, something should turn up. When entire families get stretch marks, not only the pregnant and the weight-lifters but also the kids in their puberties and the members who get obese, and no one in the family next door gets them much, not the guy bulking up or his middle-school sister or his three-hundred pound brother or his mom, it appears that there’s a stretch mark gene out there, all right, and that sometimes there’s thankfully not.
With regard to the suspected hormonal causation, a conclusion may be shaping up faster. A specific group of steroidal hormones is under close scrutiny. They are called glucocorticoids.
Glucocorticoids are secreted by the adrenal glands. They affect metabolic functions. Cortisol, one of the hormones in this group, regulates levels of glucose (sugar) through breakdown of fat and muscle. How much or how little of this sugar is present in the blood, and whether it’s used or stored, has a tremendous effect on a person’s appearance, and even on his or her health.
One fact has been confirmed: cortisol increases during puberty, pregnancy, weight-lifting, and fat gain. The reason is simply stress. All of those conditions stress the body, and stress produces more cortisol. Its upsurge consistently coincides with the appearance of new stretch marks.
When it comes to food intake and fat gain, cortisol is a double-edged sword. It doesn’t just get higher while you’re piling on the pounds; it also elevates during fasting. When you think about it, this makes sense: starvation is major stress. As a result, the ability to burn excess fat gets terribly impaired, and diet specialists have long understood that this is the primordial survival mode that kept our hungry ancestors going. Today, of course, it’s infuriating, the cruelest of ironies: until the survival mode passes, which takes weeks and perhaps even months, not eating can keep you chunky. You might even gain more weight while you starve, and get even more stretch marks.
Accordingly, child-bearing is a natural condition of stress. The cortisol is elevated, and not only because of the pregnancy; it also increases to help to complete the growth of the fetal lungs.
Extreme weight-lifting elevates cortisol to help repair over-stressed muscles.
The stresses of puberty are legendary, and during that time the cortisol rises significantly.
But does cortisol directly cause stretch marks? The jury’s still out on that. Researchers suspect that cortisol and other glucocorticoids impair collagen production. They affect many bodily processes, so why not skin protein, too? The aforementioned fact that users of hydrocortisone creams get striations where they apply it is a very strong indication that this hormone group does create scarring. So is the fact that Cushing’s syndrome sufferers, who have excessive glucocorticoids, get stretch marks for no apparent reason.
Much more research needs to be done, but the indications are clear. Perhaps in the end there will be a sure way to suppress the revealed stretch mark gene, and a way to keep the powerful glucocorticoids from altering the skin.