But use it with great caution.

It comes with side effects and less than pleasant consequences.

And it's not cheap.

Besides, the strongest versions require a prescription, which may not be covered by medical insurance unless your doctor wants to treat your acne, psoriasis, or skin cancer (not what this article's about, however).

Most insurance companies classify it as a "lifestyle" medicine. That means you take it to improve your appearance by improving your skin's health, but your skin isn't actually "sick" - just growing older.

Modern medical science - and, therefore, the medical insurance industry - regards aging itself as an inevitable condition, not a medical disease. Yes, even though it treats illnesses basically caused by aging, such as heart problems and so on.

Still, you can find over-the-counter versions that can get you started for a lot less cash.

Of course, we're talking about . . . 

Retin-A

That's the best-known name.

However, there's an entire family of retinol or retinoid versions. All of them are vitamers of Vitamin A or chemically similar to it.

Tretinoin - Retin-A - is just the most well-known.

You can find many creams containing various kinds of retinoids. Some are natural, some not.

Vital Functions of Retinoids

Because they're related to Vitamin A, our bodies do need retinoids. They support good vision, regulate the growth of bone tissue, balance immune system function, activate tumor suppressor genes, and manage the growth and differentiation of cells.

The main dietary sources are the carotene family of phytochemicals (from plants) and retinyl esters (from animals).

However, most of the retinol found in commercial skin products are synthetic.

Two Mechanisms of Action for Greater Skin Health

Retinoids help protect your skin from photoaging (caused by sunlight) in two ways. They activate:

* Your retinoic acid receptors (RARs)

* Your retinoid X receptors (RxRs)

The biochemical reactions and chains get complicated, but - basically - retinoids protect your skin's health five ways:

1. They increase collage.

2. They induce epidermal hyplasia.

3. They decrease keratoinocytes.

4. They reduce melanocyteatypia.

5. They improve glycosaminoglycan expression.

In simpler language, retinols help skin:

1. Increase tissue strength. 

Collagen is like concrete. Your skin now is like a concrete wall that's lost a lot of concrete to age.

Small wonder aging skin sags, and has wrinkles and bags. It needs solid reinforcement, and retinols provide that.

2. Increase your skin's blood supply.

Our blood is what transports nutrients to every cell of our bodies. Skin cells without a good supply of blood are like farms in a remote wilderness, unconnected to the rest of the country.

Retinol creams help your body build a road to the farm, so they receive delivery of what they've ordered from Amazon.

3. Increase the turnover of your skin cells.

Your skin has several layers, most of which you can't see.

Skin cells start out life at the very bottom, then gradually rise to the top, to your epidermis. 

That's a natural cycle, and it's good because it ensures new skin cells are always coming up to replace the old ones.

When we're young, it takes 39 days for a new skin cell to rise to the top of your epidermis. 

However, as we go north of 30, the process slows down. This leaves the older skin cells in place for longer periods of time, so it's no surprise our skin looks older than when we were in our 20s.

Retinols, however, speed up the process, so the older skin cells are gone faster, and replaced faster.

4. Increase skin hydration.

After collagen, one of the major components of healthy, youthful attractive skin is simple water.

Baby skin is plump and youthful because it's well-hydrated.

We lose that as we grow older - and drier skin makes us look older.

One Retinol Study

In 2007, scientists studied a number of subjects. For 24 weeks, half of them placed a cream of 0.4% retinol lotion on their faces. They other half got a placebo.

By the end, the group applying retinol saw a decrease in fine lines and wrinkles.

The scientists could actually see where brand-new blood vessels grew to support this healthier skin.

3rd Generation Retinols

These versions of retinol are more stable and may have fewer side effects than the more common Retin-A and earlier generations.

One 3rd generation retinol, adapalene, was approved by the FDA to treat acne in 2019.

It's now available in over-the-counter products. 

Because it's a more stable molecule, adapalene doesn't break down in sunlight and cause skin irritation.

As you have probably heard, Retin-A and other earlier retinol products cause sensitivity to sunlight. Applying those products to your skin and then going out into daylight can cause a great deal of pain.

Use Caution

1. Even if you use adapalene, be very careful about exposing your skin to sunlight, or you could wind up with the most painful - and skin destructive - sunburn of your life . . . followed by incredible peeling.

Start small. Apply only a drop at first - and do so at night. 

And don't even put it on every night, just every two to three days. That's to give your skin a chance to get used to it.

That could well take two to three months.

2. Look for a lotion that has a good base to contain the actual retinol.

Beneficial ingredients for the base include Vitamin E, anti-irritants, Vitamin B3 and antioxidants.

3. Be careful how much you use.

Just like Vitamin A, retinols wind up in your liver, and are toxic in high amounts.

Therefore, concentrate the use of retinols on your face and other small amounts of exposed skin. 

https://differin.com/learn/faqs

https://www.ncbi.nlm.nih.gov/books/NBK482509/

https://en.wikipedia.org/wiki/Retinoid

https://honeybeehealth.com/blog/meds-wellness/retin-a-tretinoin-and-insurance-coverage-its-complicated

https://www.youtube.com/watch?v=n5Bm5U7T254

https://www.youtube.com/watch?v=H9NAF5Q5B5k

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8750127/