Dr. Ron’s Research Review – September 11, 2013

© 2013

This week’s research review focuses on dry skin.

Dry skin (xerosis) is common in older adults, affecting up to 50%. It is not considered to be a normal part of aging. (White-Chu and Reddy 2011)

Lecithin, vitamin A and Cod Liver Oil

In 1950, Pottenger identified dry skin as a common form of fat dyscrasia. He recommended lecithin, vitamin A and cod liver oil. He discusses how essential fatty acids have disappeared from our modern diet, and cautions against the use of hydrogenated oils. (Pottenger 1950)

Gamma-Linolenic Acid

A recent study of 130 people with dry skin found that dietary supplementation with gamma-linolenic acid (200 mg) improves skin parameters in subjects with dry skin and mild atopic dermatitis. (Kawamura, Ooyama et al. 2011)

Magnesium-rich Dead Sea Salt

Another study found that bathing in magnesium-rich Dead Sea salt solution improves skin barrier function, enhances skin hydration, and reduces inflammation in atopic dry skin. (Proksch, Nissen et al. 2005)

Topical Nicotinamide

Topical nicotinamide (2% cream) was found to have a moisturizing effect on atopic dry skin, and was significantly more effective than white petroleum jelly. (Soma, Kashima et al. 2005)

Dr. Ron


Abstracts

Dietary supplementation of gamma-linolenic acid improves skin parameters in subjects with dry skin and mild atopic dermatitis

         (Kawamura, Ooyama et al. 2011) Download

Disruption of the skin barrier function caused by epidermal hyper-proliferation, results in the skin becoming dry and showing high transepidermal water loss (TEWL). Gamma linolenic acid (GLA) is reportedly efficacious for treating TEWL and epidermal hyper-proliferation. In this study, to elucidate the effect of GLA-rich oil on skin function, GLA-containing food was given to adults with dry skin or mild atopic dermatitis and skin parameters were evaluated. In the results, we recognized beneficial effects on the TEWL index. The efficacy of GLA was also demonstrated to be statistically significant especially in subjects with pro-inflammatory features. The results suggest that the mechanism of improvement of skin barrier has been associated with possible generation of anti-inflammatory metabolites from GLA. The clinical physician also confirmed that none of the subjects showed any noteworthy side effects. GLA-enriched food appears to be safe and to improve skin barrier function in subjects with dry skin conditions and mild atopic dermatitis.

A common form of fat dyscrasia; dry skin

         (Pottenger 1950) Download

Bathing in a magnesium-rich Dead Sea salt solution improves skin barrier function, enhances skin hydration, and reduces inflammation in atopic dry skin

         (Proksch, Nissen et al. 2005) Download

Magnesium salts, the prevalent minerals in Dead Sea water, are known to exhibit favorable effects in inflammatory diseases. We examined the efficacy of bathing atopic subjects in a salt rich in magnesium chloride from deep layers of the Dead Sea (Mavena(R) Dermaline Mg(46) Dead Sea salt, Mavena AG, Belp, Switzerland). Volunteers with atopic dry skin submerged one forearm for 15 min in a bath solution containing 5% Dead Sea salt. The second arm was submerged in tap water as control. Before the study and at weeks 1-6, transepidermal water loss (TEWL), skin hydration, skin roughness, and skin redness were determined. We found one subgroup with a normal and one subgroup with an elevated TEWL before the study. Bathing in the Dead Sea salt solution significantly improved skin barrier function compared with the tap water-treated control forearm in the subgroup with elevated basal TEWL. Skin hydration was enhanced on the forearm treated with the Dead Sea salt in each group, which means the treatment moisturized the skin. Skin roughness and redness of the skin as a marker for inflammation were significantly reduced after bathing in the salt solution. This demonstrates that bathing in the salt solution was well tolerated, improved skin barrier function, enhanced stratum corneum hydration, and reduced skin roughness and inflammation. We suggest that the favorable effects of bathing in the Dead Sea salt solution are most likely related to the high magnesium content. Magnesium salts are known to bind water, influence epidermal proliferation and differentiation, and enhance permeability barrier repair.

Moisturizing effects of topical nicotinamide on atopic dry skin

         (Soma, Kashima et al. 2005) Download

BACKGROUND: Certain moisturizers can improve skin barrier function in atopic dermatitis. The effect of topical nicotinamide on atopic dry skin is unknown. We examined the effect of topical nicotinamide on atopic dry skin and compared the results with the effect of white petrolatum in a left-right comparison study. METHODS: Twenty-eight patients with atopic dermatitis, with symmetrical lesions of dry skin on both forearms, were enrolled, and were instructed to apply nicotinamide cream containing 2% nicotinamide on the left forearm and white petrolatum on the right forearm, twice daily over a 4- or 8-week treatment period. Transepidermal water loss and stratum corneum hydration were measured by instrumental devices. The amount of the stratum corneum exfoliated by tape stripping (desquamation index) was determined by an image analyzer. RESULTS: Nicotinamide significantly decreased transepidermal water loss, but white petrolatum did not show any significant effect. Both nicotinamide and white petrolatum increased stratum corneum hydration, but nicotinamide was significantly more effective than white petrolatum. The desquamation index was positively correlated with stratum corneum hydration at baseline and gradually increased in the nicotinamide group, but not in the white petrolatum group. CONCLUSIONS: Nicotinamide cream is a more effective moisturizer than white petrolatum on atopic dry skin, and may be used as a treatment adjunct in atopic dermatitis.

Dry skin in the elderly: complexities of a common problem

         (White-Chu and Reddy 2011) Download

Dry skin, or xerosis, is a common skin condition in older adults, but it is not a normal part of aging. The geriatric patient may have several incurable, but treatable, chronic diseases that affect their skin. Xerosis in older adults is multifactorial: intrinsic changes in keratinization and lipid content, use of diuretics and similar medications, and overuse of heaters or air conditioners all contribute. Xerosis causes pruritus, which then leads to excoriations and risk of skin infections. Patients can minimize the effect of xerosis by increasing the ambient humidity, modifying their bathing technique and products, and using emollients to replace the lipid components of the skin. Care should be made to avoid skin sensitizers, such as lanolin, aloe vera, and parabens, that are commonly found in emollients. These may lead to a delayed hypersensitivity reaction. This contribution reviews the intrinsic and extrinsic aging processes of skin aging and advises practical changes in environment and emollient application that can be distributed to patients.


References

Kawamura, A., K. Ooyama, et al. (2011). "Dietary supplementation of gamma-linolenic acid improves skin parameters in subjects with dry skin and mild atopic dermatitis." J Oleo Sci 60(12): 597-607. [PMID: 22123240]

Pottenger, F. M., Jr. (1950). "A common form of fat dyscrasia; dry skin." South Med J 43(2): 165-8. [PMID: 15401663]

Proksch, E., H. P. Nissen, et al. (2005). "Bathing in a magnesium-rich Dead Sea salt solution improves skin barrier function, enhances skin hydration, and reduces inflammation in atopic dry skin." Int J Dermatol 44(2): 151-7. [PMID: 15689218]

Soma, Y., M. Kashima, et al. (2005). "Moisturizing effects of topical nicotinamide on atopic dry skin." Int J Dermatol 44(3): 197-202. [PMID: 15807725]

White-Chu, E. F. and M. Reddy (2011). "Dry skin in the elderly: complexities of a common problem." Clin Dermatol 29(1): 37-42. [PMID: 21146730]