Ingredient focus: Niacinamide

This is Part Two on Niacinamide. In Part One, (LINK attached here), I outlined why Niacinamide is important to energy storage in our bodies and how it is a skin lightener.

Today’s blog outlines the functions of Niacinamide

There is general consensus about the benefits of functions of Niacinamide by independent researchers and pharmaceutical companies. (This is one of the few actives where the research/clinical studies are difficult to fault).

(Notes: at the end of this blog, there are 3 brief explanatory notes on the skin barrier, lipid matrix, impaired barrier signs, and desquamation.)

Benefit one: Moisturising Effect

In this study, Soma et al, compared the moisturising effect of Niacinamide to White PETROLATUM on atopic skin (very dry skin). Why white petrolatum, I hear you ask?.

White Petrolatum is the most commonly used moisturiser for dry skin. It’s also the (informal) standard against which the performance of other moisturizers is assessed. Its application to healthy human skin reduces transepidermal water loss (TEWL), which in turn means that there is more water content in the skin. Also, it accelerates skin barrier recovery of skin.

Soma et al measured TEWL, the water content of the stratum corneum and desquamation index. (see below for a brief explanation on what Desquamation is) and found that:

• Niacinamide usage caused LESS TEWL, resulting in higher levels of hydration in the Stratum Corneum. That is, Niacinamide caused the skin to lose less water than it ordinarily would and this resulted in higher levels of skin hydration.
• Soma et al thought that desquamation in dry skin was high. This was wrong. Desquamation in dry skin was low and the Niacinamide increased this, which overall is a good thing. One of the characteristics of aging skin is lower levels of desquamation.

Benefit Two: Niacinamide has a similar effect to 1% clindamycin in Acne

Shalita et al tested the safety and efficacy of 4% Niacinamide gel with 1% clindamycin gel for the treatment of inflammatory acne. After 8 weeks both treatments, produced comparable beneficial results, namely reduction in acne lesions and acne severity.

The Niacinamide results were impressive: 82% of subjects with inflammatory acne treated with 4% Niacinamide showed significant improvement in papules/pustules (about 60%) and severe acne (about 50%).

Benefit Three: Niacinamide reduces the production of sebum

Viable human tissue (from facelift surgeries) were treated with Niacinamide in a lab for 4 days. Niacinamide produced significant reductions in total sebum lipogenesis. That means, there was a reduction in the production of sebum (also called lipogenesis) that was dependent on the dose of Niacinamide used.

Benefit Four: Niacinamide increases ceramides, fatty acids , cholesterol and sphingolipids

The lamellar lipid matrix in the Brick and Mortar model of the skin or the Stratum Corneum lipids are rich in Ceramides (such as sphingolipids), Free Fatty Acids and Cholesterol. The presence of these is vital to the normal functioning of the epidermal barrier, including permeability. If you apply (e.g.) a topical cream, the active ingredients find their way through your skin via this permeable barrier. If this barrier is dysfunctional, it will (e.g.), let unwanted pathogens in and cause the skin to lose valuable lipids.

Tanno et al (2000), noted that in aged skin and dry skin, the Stratum Corneum lipids are reduced. They found that

• Niacinamide increased the biosynthesis of Ceramides AND other intercellular lipids, namely Free Fatty Acids and Cholesterol
• Niacinamide also increases Ceramides and other intracellular lipids in the Stratum Corneum

One of the effects is reduced TEWL (see above).

Benefit Five: Niacinamide as an anti-aging ingredient

Bissett et al (2004) conducted a study using Caucasian female subjects over a 12 week period using inter alia 5% topical Niacinamide. In relation to a 5% Niacinamide topical application, the results were as follows:

• 5% topical treatment was well tolerated and did not induce skin irritation, redness, dryness, burn, sting or itchiness
• A 5% Niacinamide
  • Prevented an increase in facial red blotchiness
  • Reduced facial skin fine lines/wrinkles: At 8 weeks, a small but significant reduction in fine lines/wrinkles. By week 12, the difference was a 5.5% reduction in fine lines/wrinkles.
  • Prevented an increase in hyperpigmented spot area
  • Improved skin sallowness (or skin yellowing)

Well done, you’ve reached the end of today’s blog. I will write more on Niacinamide products in future blogs.

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Note 1: on the skin barrier and the lamellar matrix

Functions of the skin barrier

The SC is the body’s first barrier from the external environment and performs most of the skin barrier’s function.  The two components of the stratum corneum, the extracellular lipid matrix and corneocytes (protein structure) perform different functions:

– The protein structure provides mechanical reinforcement to the skin, protects the skin from UVR damage, acts as an immunological barrier and maintains hydration.  The protein structure itself holds water.

– The lipid matrix is the permeability barrier and therefore allows for (e.g.) nutrients to pass through; it excludes toxins and most importantly, it is a waterproof barrier that prevents Transepidermal water loss (TEWL). Other barrier functions of the skin include regulating temperature and maintaining the skin’s pH at about 4

Note 2: An impaired barrier (caused by excessive washing) is characterised by:

1) After-wash tightness (AWT)

For example, cleansing will cause hyper-hyrdation immediately after washing followed by rapid evaporation of water to lower equilibrium levels of water in the skin, leading to after wash tightness.   The skin proteins have a reduced ability to bind and hold water and so the skin is drier after washing.  Also, there is a reduction in the Natural Moisturing Factors and the skin’s viscoelasticity, manifesting as AWT. 

2) Skin dryness, scaling and roughness

In addition, lipids are damaged causing cholesterol and fatty acids to be removed from SC – even after one wash. This causes dry skin and the SC is more vulnerable to chapping/cracking and therefore barrier breakdown. With barrier breakdown comes TEWL (transepidermal water loss)..

3) Skin irritation, redness and itching.

These are all inflammatory responses to surfactants, and the thing is the surfactant does not even need to go deep into the skin.

Note 3: Desquamation

As we get older, “keratinization” of the facial skin increases: corneocytes (dead cells) in the topmost layer of our skin (the Stratum Corneum), stick together more tightly becoming harder to remove.

Also, as we age, the skin’s natural ability to desquamate decreases. Desquamation is a natural cellular process whereby our epidermis renews itself every 28 days. As we get older this process slows down and (e.g.) can reach 40 days. This results in roughness, sallowness, uneven skintone, hyper-pigmentation, lines and wrinkles.

Note 4: What is skin sallowness?

Between the ages of 20 – 80 years, glycation of protein increases 5x times. Glycation (or the Maillard Reaction) is a spontaneous oxidative reaction between protein and sugar resulting in cross-linked proteins that are yellow-brownish in colour. These can accumulate in collagen and have a long half-life. Niacinamide appears to reduce glycation through the anti-oxidant activity of NADH and NADP…

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Sources and uses

Tanno O, Oya Y, Kitamura N et al. Nicotinamide increases bio-synthesis of ceramides as well as other stratum corneum lipids to improve the epidermal permeability barrier. Br J Dermatol 2000;143: 524–31.

Niren NM,  Pharmacologic doses of Nicotinamide In the treatment of Inflammatory skin conditions: a review. Cutis (Jan. 2006), 77(1 Suppl):11-6.

Hakozaki T, Mlnwalla L Zhuang J el al. The effect of Niacinamide on reducing cutaneous pigmentation and suppression of melanosome transfer. Br. J Dermatol. (July 2002), 147 (1): 20-31

Gehring W, Nicotinic acid/Niacinamide and the skin J Cosmet Dermatol. 2004 Apr;3(2):88-93.

Shalita AR, Smith JG et al, Topical nicotinamide compared with clindamycin gel in the treatment of inflammatory acne vulgaris Int J Dermatol. 1995 Jun;34(6):434-7.

Soma Y, Kashima M et al, Moisturizing effects of topical nicotinamide on atopic dry skin. Int J Dermatol. 2005 Mar;44(3):197-202. 

Bissett, D. L., Miyamoto, K. et al, Topical Niacinamide reduces yellowing, wrinkling, red blotchiness, and hyper pigmented spots in aging facial skin. Int J Cosmet Sci. 2004 Oct;26(5):231-8

Draelos ZD, Ertel K, Berge C. Niacinamide-containing facial moisturizer improves skin barrier and benefits subjects with rosacea. Cutis. 2005 Aug; 76(2):135-41

Biedermann, K., Lammers, K., Mrowczynski, E., Coombs, M., Lepp, C., El-Nokaly, M., and Burton, E., Regulation of sebum production by niacinamide, 60th Annual Meeting American Academy of Dermatology, New Orleans, 2002 J Cosmet Laser Ther. 2006 Jun;8(2):96-101.

Levin J et al How Much Do We Really Know About Our Favorite Cosmeceutical Ingredients? JCAD Online Editor | February 5, 2010