The year was 2000. They told us that nanotechnology is great and that it is the “decade of nanotechnology”. Then they tried to sell us stuff by using the word “nano”.
Ten years later, Robin Cook wrote a medical thriller titled “Nano”.
Soon after, some people began to say that nanotechnology is bad. They ask for money to fund “non-profits” to put pressure on Congress so that everything nano can be banned.
What is nano? You probably learned about this term in high school, when studying the metric system. The nanometer is one thousandth of a micrometer, which is one thousandth of a millimeter, etc.
How small is a nanometer? Below is a (logarithmic) scale showing where the atom is compared to a giant sequoia.
Where will you encounter the terms nanotechnology or nanoparticles in skin care? In marketing. These are used as scientific-sounding terms to convey extra penetration of ingredients into the skin. In these cases, just ignore the words completely. It was introduced into the advertising world by marketing departments. You need to check the ingredient list, or ask about the ingredients in the SAS forum.
Remember Myth #1? “The skin is impermeable”? It is NOT.
The skin is not an impenetrable film of plastic, it is a biological system with plenty of entry points, especially in aging skin.
If the skin were impermeable, you clearly would need that delivery system consisting of those nanoparticles designed by that famous scientist in Switzerland. Unfortunately, that famous scientist in Switzerland does not exist, or never published anything in a reputable scientific journal. More important, he is lying about skin properties: the skin is not impermeable and you don’t need any delivery system to get an active ingredient into your skin. Whatever you apply to the skin will be absorbed, for better or for worse.
The outermost layer of the skin, the stratum corneum, limits water loss from the body to the environment. It allows human organisms that depend totally on water, to walk around in the Arizona desert and still be able to live. The stratum corneum also limits penetration of water and chemicals into the skin, slowing absorption of nutrients (and noxious chemicals) applied topically. “Limits” does not mean that this layer is impermeable, as shown by trans-epidermal water loss. Trans-epidermal water loss can be measured easily with a laboratory instrument, and it increases with age and skin damage. In photo-aged skin the absorption of external nutrients will be higher than in young skin, just like trans-epidermal water loss is higher.
The absorption of water-soluble nutrients through the skin will increase with skin humidity, so it is a good idea to take advantage of the skin’s higher permeability after a shower or bath. Even a low uptake of nutrients, such as amino acids, applied topically should substantially improve the health of skin deprived of nutrients by the decrease of blood supply to the dermis that occurs to all of us when we age. This is valid for all useful actives applied topically. You don’t need to absorb 100% of them, so forget about “delivery systems” because you don’t need them.
The Real Nanoparticles
The Latest Silliness: Nanoparticles as Endocrine Disruptors
In Short: The Facts
-Dr. Hannah Sivak