Dermal Delivery of the Essential Topical Micronutrients: Part Two

I didn’t realize until after I’d written the previous blog post that it begged for a sequel; knowing which micronutrients are necessary to maintain healthy skin is of course important, but if micronutrients don’t travel to where they need to go, not to mention be in good shape and ready to work once they’ve arrived, then they’re useless (even worse than useless in some cases, when being in the wrong place can harm the skin). So, in a follow-up to the discussion in Part One concerning which micronutrients to use we focus this time on where micronutrients need to go, i.e., to which layers of the skin, their mode of transport, and what they do once they’ve reached their destination. The short term for all this eventful activity is Dermal Delivery. Dermal Delivery is the opportunity to deliver important micronutrients topically which means you must have good formulation AND good chemistry to start with, not just a good ingredient deck (oh and let’s not forget about a deep understanding of skin function and the microbiome). Think about all of this when choosing your skincare and note the values of the company making your products. Companies need to know how to properly formulate to deliver ingredients effectively and have the heart and knowledge to always make that the priority. 

This is no easy feat as dermal delivery presents a host of mind-twisting challenges for formulators, greatly surpassing in difficulty level puzzlers of the recent past like resourcing natural ingredients or eliminating harmful preservatives. Indeed those two categories, so relentlessly exploited by the natural skin care world as to leave barely a lichen-covered stone unturned, a tropical seed unpressed or a “toxin” unvillified have become, almost overnight, beside the point. Museum pieces in their own time.

I’m here to emphasize Dermal Delivery again, now, because consumers expect results, as they should. The implications for those of us in the industry determined to satisfy this entirely reasonable demand are obvious. We know the defining characteristics of effective skin care products, that is, ones that actually improve skin health, to be that they deliver:

• the appropriate micronutrients
• properly stabilized
• accompanied by suitable partners  
• in the right proportions
• to the layers of the skin where they will be most effective.  

The list of Dermal Delivery rules will of course expand pending future investigative research, but adhering to the ones we can identify now is already a tall order, involving many moving parts. For instance, we still have much to learn about corralling the power of the giants of the micronutrient realm, Vitamins A and C, even though they’ve been well researched over decades.  

Let’s take a look at the journeys some of the important micronutrients previously discussed undertake—how they travel to their destinations and what they do once they’ve arrived. We can start by taking the A-train—all aboard!

Vitamin A

Description: Vitamin A is the normalizing vitamin belonging to the chemical family known as retinoids. 

Delivery Method: These retinoids come with a built-in delivery system. Once the retinoid converts to retinoic acid, RA (retinoic acid) travels to the dermis and attaches to RARs (retinoic acid receptors) on the surface of fibroblast cells that reside there. These receptors direct the performance of a multitude of tasks: initiating collagen production, normalizing skin cell development, regulating sebum production and inhibiting enzyme activity governing collagen breakdown and transcription factors like AP-1 which plays a role in inflammation.  

The Challenges for Formulators

Retinol is an oil-soluble ingredient with its destination to RARs on fibroblasts in the dermis clearly mapped out. The problem with retinol is stabilization rather than delivery. Retinol is extremely unstable, and breaks down in the presence of oxygen. It also does not do well in the low pH range required of a good skin serum. For these reasons most dermatologists used to recommend retinoic acid, even though it needed a prescription and there were often problems with facial retinization causing irritation. New encapsulation techniques have changed all that, and now retinol is preferred by many dermatologists over retinoic acid, because the mechanisms involved in inducing change are mediated by tightly regulated conversion of retinol to retinoic acid. In other words, the skin converts retinol to RA as needed—which makes for a more efficient and natural delivery method, and one much less likely to cause irritation. You get the same results; it just may take a bit longer to get there.

The Challenges for Consumers

Not all retinoids are created equal—you need to make sure you are getting a retinoid that is either retinoic acid to begin with, such as prescription products like Retin-A, or Vitamin A derivatives that convert to retinoic acid, like retinol or retinaldehyde.  

Retinoids to look for: encapsulated retinol, Retin-A or other prescription, Adapalene or Differin if you have acne, retinaldehyde.

Retinoids to avoid: retinyl palmitate and retinyl proprionate do not convert to retinoic acid.

Natural retinols found in rosehip seed oil and the like are fine to use, but don’t use them as a retinol substitute—you’re not getting sufficient retinol converting to retinoic acid from them.  

Bottom line: there is a retinoid for almost everyone (the exceptions are pregnancy, breastfeeding, and people under age 30 who have no skin problems)—it may be retinol, it may be Differin or Retin-A. Or use ours! Gentle Retinol Night Serum or Treatment Retinol Serum (they are the same product in different packaging). Once you’ve found the one that works for you use it faithfully. You’ll be glad you did.

Vitamin C

Description: l-ascorbic acid is a vitamin that we need to get from dietary sources as we are one of the very few mammals that does not synthesize it. Vitamin C plays an important role in a number of bodily functions, but it is absolutely vital to healthy skin as we can’t produce collagen without it. It is also a powerful antioxidant and photoprotectant.  

Delivery Method: Basically it doesn’t deliver in the absence of extraordinary coddling and cajoling. It is the opera diva of the micronutrient world; it oxidizes when exposed to air, heat and light, and when you put it in liquid it goes berserk—oxidizing to become a pro-oxidant instead of an antioxidant in a very short time. The dermal delivery rules regarding ascorbic acid are very, very strict, and if they are not followed to the letter this diva can do you more harm than good. 

The rules are:

• must be stabilized 
• to make collagen, must penetrate to the dermis where the fibroblasts reside. Vitamin C is active inside the cells, where it hydroxylates (adds hydrogen and oxygen) to two amino acids, proline and lysine. Without Vitamin C collagen formation is disrupted. 
• to make collagen, must be ascorbic acid, or be able convert to ascorbic acid  

Marie Veronique serums that are well formulated and deliver Vitamin C topically:

• Vitamins C+E+Ferulic Serum 
• C-Therapy Serum

Two popular ways of dealing with Vitamin C simply don’t work because they are not following the rules of dermal delivery.

1. Some companies put large amounts of ascorbic acid in water, knowing that it will degrade but trusting that the product will be used up before all the Vitamin C has disappeared. The rules of dermal delivery they are breaking: the micronutrient is not well stabilized, though it is often hooked up with great partners that help with stabilization. Penetrability and ability to pass through to the dermis do not seem to be addressed. If you like these products use them up quickly to get the best benefit from the ascorbic acid.
2. Other companies provide the Vitamin C separately, in powder form, advising the consumer to mix it with water just before use. This works well to forestall Vitamin C degradation until time of use, but once it’s mixed with water look out. Here’s what happens:  

• Putting ascorbic acid in water lowers pH as the ascorbic acid reacts with water to create hydronium ions (pH is determined by the number of hydroniumions in solution). Applying this very acidic solution to skin can irritate the skin and even cause breakouts.  
• No penetrability. The epidermal layer is impermeable to water and water soluble products. The ascorbic acid dissolves in the water, but when the solution is applied to the skin the water evaporates, leaving the Vitamin C to recrystallize on the skin’s surface. Not only does it not penetrate it can sensitize the skin, making more problematic the use of better-formulated Vitamin C serums later on.
• Putting the powder in oil is not effective, as Vitamin C is water-soluble and oil-insoluble. It just clumps up and sits on the surface of the skin.
• This product breaks all the cardinal rules of dermal delivery:

• Because it’s a strong acid its one claim to fame is that it is a powerful exfoliant. People say it brightens their skin, but using an exfoliant like lactic acid once a week will work just as well if not better, as LA doesn’t dry out the skin. LA has humectant properties and increases natural ceramides in skin.