Eqqualberry NAD+ Peptide Boosting Serum Versus Pfect-A Pro Age Cellular Booster NMN + NAD+ Serum

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Our NAD+ levels naturally decline with age and several DNA repair mechanisms critical to skin health are directly dependent on NAD+ to function.

In-vitro studies on human fibroblasts have shown that exogenous NAD+ can protect agsinst UV-induced extrinsic and intrinsic aging.

Here's a big caveat: NAD+ is a large, polar moleculate that has difficult penetrating the skin's stratum corneum. It also degrades quickly when exposed to light, heat, or pH changes. That's why brands prefer to use smaller, more stable precursors like NMN or NR.

The optimal stability for NAD+ is a pH of 6-7.5 and it is typically used in concentration ranges from 0.5-2%.

If you're looking for the most well-studied topical route to support your skin's NAD+, niacinamide is your best bet.

In lab and animal studies, NMN has demonstrated:

This ingredient also breaks down into niacinamide even as it degrades.

There are two major caveats to this ingredient:

1) It is not stable and degrades quickly in water-based formulations.
2) Most of the skin data is still prelinical (cell and animal studies) and human clinical trials are still limited.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.