Examining whether vitamins and nutrients can really be absorbed through the skin using products like patches and creams.
Examining whether vitamins and nutrients can really be absorbed through the skin using products like patches and creams.
When we think about taking nutrients into our bodies, we usually think about swallowing them, in the form of pills, powders, or that radical format known as food. But an increasing number of products promise to provide nutrition in the form of vitamin patches and creams. Some even worry about vitamin-charged skin care products leading to accidental toxicity.
Today, we’re going to take a look at how much nutrition you may be absorbing through your skin.
I’m Monica Reinagel, host of the Nutrition Diva podcast–which is now in its 16th year, with over 50 million downloads! I know many of you listening have been following this podcast since the beginning. Thank you! for your support. I also provide expert commentary on nutrition and health to a variety of national media outlets. You can find more information about my keynote speaking and workplace wellness programs at wellnessworkshere.com
And now, let’s talk transdermal nutrition!
When we talk about nutrient absorption, we’re usually talking about the absorption of nutrients from the digestive system into the bloodstream. But instead of swallowing a handful of pills and worrying about whether or not they are being absorbed, why not bypass the digestive tract altogether and apply them directly to your skin?
Nicotine, estrogen, testosterone, and certain pain medications can all be delivered through the skin through medicinal patches, gels, or creams. Why not vitamins and minerals?
The US military, for example, is working on a skin patch that could deliver nutrients and other compounds to soldiers “during periods of high-intensity conflict,” when getting adequate nutrition from food might be challenging. Scientists working on the project don’t expect to have anything ready for field testing for another five or ten years.
But you don’t have to wait for those fusty old scientists to dot every i and cross every t. There are companies who will take your money RIGHT NOW for patches, gels, and bath salts containing magnesium, vitamin D, CoQ10, and various other herbs and nutrients that claim to alleviate nutrient deficiencies, boost your energy, alleviate hangovers, boost your libido, and (of course) help you lose weight. However, I’m skeptical that any of these substances will actually end up in your bloodstream. And you should be too.
The skin is actually designed to be a fairly impenetrable barrier. And good thing, too. Imagine for a moment if everything that touched your skin ended up in your bloodstream! (No, really, give that one some thought…)
Of course, lotions and cosmetic potions still tout their vitamin-drenched formulas. Which brings me to a question I recently got from Nicky, who wrote:
“I’ve read that the European Union limits the amount of retinol that can be used in facial products, because of fears that higher amounts might push consumers over the maximum safe daily intake of Vitamin A. I never imagined that my retinol face cream would be a meaningful source of vitamin A in my body. Is this a realistic concern?”
The EU does, in fact, regulate the amount of retinol in facial products limiting it to 0.3%. There are no such limits in the U.S. and here you will find over-the-counter skin care products with 1% retinol or even more. But, I don’t think that this is anything we need to worry about.
While nutrients may (or, then again, may not) have cosmetic effects on the surface of the skin, very little if any of those nutrients are penetrating beyond the skin’s tough out laters. That’s why we can slather our skin with mineral-based sunscreens all summer long without developing a zinc overload! Studies have shown that the topical application of zinc-containing sunscreens has minimal if any impact on the amount of zinc in your blood.
For that matter, studies have found that magnesium is not very effectively absorbed through the skin, either. That doesn’t seem to hurt the sales of topical magnesium products claiming to be a more effective way to absorb magnesium. Buyer beware.
And, while retinoids (which are derivatives of Vitamin A) have more impact on the structure and function of the skin than most nutrients, studies have found that use of retinol containing skin care products has little to no detectable effects on systemic Vitamin A levels.
So, what’s with the European Union? Well, they appear to be taking a very conservative stance toward these popular anti-aging skincare products. (If you’re visiting friends in Europe, now you know what to bring them as a gift!)
In order to be absorbed through your skin and into your bloodstream, a compound needs to have at least two things going for it. It needs to be lipophilic, or fat-soluble. And it needs to be very, very small. A lot of the compounds found in commercially-marketed transdermal nutrient patches are neither.
Of course, there are ways to get around these limitations. You can break a large molecule down into nanoparticles, or encase it in a substance that diffuses more easily into the lipid layer of the skin. You can use tiny little needles to poke tiny little holes in the skin, which allows the substance to penetrate into the deeper tissues. You can use chemicals to alter the surface of the skin and make it more porous. You can even use electrical stimulation to open the pores, or a technique known as microdialysis.
All of these are strategies that are currently in use or being developed by pharmaceutical companies and the military. However, you can be pretty sure that $2 vitamin D patch doesn’t include any of those features. Perhaps that’s why the product website includes the disclaimer, “This product has not been tested for safety or efficacy.”
No, seriously. It actually says that.
Similarly, I very highly doubt that much if any of the green tea extract or garcinia cambogia embedded in their weight loss patch is actually going to end up in your bloodstream. Then again, even if it did, it probably wouldn’t result in noticeable weight loss.
On the plus side, sellers of transdermal patches point out that they completely avoid the problem of nausea or stomach upset that pills can sometimes cause. They sure do! You could also avoid stomach upset by dissolving your supplements in water and using it to water your plants—a nutrition strategy which would be about as effective as an over the counter vitamin patch.
By the way, the FDA does not classify transdermal patches as dietary supplements and considers marketing them as such to be health fraud. And some users have reported skin irritation from the adhesives used to affix them to your skin.
If you have a question you'd like me to answer, you can email me at nutrition@quickanddirtytips.com You can also leave me a message at 443-961-6206
If you’re looking for more support for healthy weight management, please check out the tools and resources that are at weighless.life. where I help people create habits, mindset, and lifestyle that help them weigh less without dieting. That’s at weighless.life
I’d also like to invite you to check out my other podcast. It’s called the Change Academy, where we explore the art and science of creating positive behavior change, both in our own lives, and in our workplaces and communities. You can find it on all the major podcast platforms. Just search for Change Academy.
Nutrition Diva is a Quick and Dirty Tips podcast. Our team includes Brannan Goetschius, Nathan Semes, Davina Tomlin, Holly Hutchings, and Morgan Christianson.
That's all for this episode. Thanks for listening! I'll see you next week.