Efficacy and tolerability study of Promega-7 Lotion in skin conditioning in aged skin
The skin is the body’s largest organ with a number of vital functions including; operating as an effective barrier to the external environment and assisting in the regulation of body temperature through heating and cooling. To assist in maintaining its barrier function the skin operates with a slightly oily covering, which also helps prevent unnecessary water loss. As the skin is the front line for protection against physical abrasions, it also needs to be efficient in its ability to repair breaks in the skin integrity. This is achieved more effectively when the skin is well hydrated and supplied by sufficient blood flow.
As we age the skin tends to get thinner and dryer1. In women this occurs more dramatically after menopause, usually somewhere between the ages of 45 and 55. After this time the amount of estrogen produced significantly decreases2. As the skin is highly sensitive to estrogen, in older women (and men), there is a reduction in sebaceous gland production resulting in skin that is drier and thinner. The dermis also becomes less active, the elastin fibers lose their structure, and the skin becomes wrinkled and may sag. Signs of earlier sun damage may also appear, including pigmentation changes, such as age spots or mottled areas2.
In younger people skin cells are replaced about every 21 to 40 days. However, as you get older, the rate of replacement decreases markedly2. As more cells accumulate on the surface, the skin can feel dense and rough, with dry patches. This reduces the efficiency of the skin as a barrier allowing increased moisture loss contributing to poorer hydration. The slowdown in cell growth means that aging skin also becomes slow to heal - especially in the very elderly2. Cuts, scratches, and minor wounds that would have healed readily in younger skin now take much longer. This may be especially noticeable in the lower legs.
To help combat these deleterious consequences of aging skin strategies to ensuring skin cleanliness and hydration/moisture content are recommended3.
While there are a number of skin care/moisturising products in use in Australia addition of macadamia oil as an active ingredient in the skin care cosmetic range is relatively recent. Macadamia oil has some unique features including having the highest content of palmitoleic and linoleic acid of any natural oil4. This is relevant because as we age the proportion of palmitoleic acid in our skin decreases making the skin less supple, though in some areas such as eyelids the decrease appears to be less rapid. In addition, due to its high palmitoleic acid content macadamia oil penetrates the skin easily5 and is purported to maintain skin hydration better than regular moisturisers without leaving an oily residue. It is argued that these fatty acids maintain the skins natural water barrier function; minimising both excess oiliness and excess dryness. A reduction in age spots, fine lines and wrinkles and an increase in elasticity of the skin after regular use have also been claimed.
This study will assess the validly of these claims in relation to the application of the “commercial-in-confidence” formulation of the macadamia oil based skin cream Promega-7.
The hypothesis central to this project is that the macadamia based skin cream Promega-7 will significantly improve various aesthetic and dermatological skin measures.
This study aims to assess whether topical application of Promega-7 in healthy human adults: Assessed via objective tests by research team.
a) Decreases wrinkles, fine lines / course wrinkles;
b) Decreases age spots, dorsal hand lentigines;
c) Decreases skin dryness;
d) Increases skin integrity, reduction of skin tears
e) Improves dull skin
The study also aims to assess the tolerability of Promega -7 (assessed via subjective questionnaire completed by participant at day 21 and 42)
d) Stinging / Burning
This study is a double-blind, single-centre, parallel efficacy trial.
Inclusion/Exclusion criteria: Participants recruited into this study will be adults:
- Aged >45 years
- Have Fitzpatrick Skin types 1 – 3 (ideal);
- Generally well;
- Who have been cancer free for two years;
- With no known nut allergies;
- Have not undergone cosmetic surgery involving any of the testing areas;
- Able to avoid professional manicures for the duration of the study;
- No facial resurfacing treatment in the last month
- Who will discontinue use of a tanning booth during the study period
- Who will discontinue use of other skin products during the study period
Farage MA, Miller KW, Elsner P, Maibach H. Characteristics of the Aging Skin Adv Wound Care (New Rochelle). 2013 2(1):5-10.
Thornton M. Estrogens and aging skin. Dermatoendocrinol. 2013, 1;5(2):264-270.
Victorian government health information. http://www.health.vic.gov.au/older/toolkit/09SkinIntegrity/ [accessed Feb 2014].
USDA Nutrient Database for Standard Reference, 2011 [Online], U.S. Department of Agriculture, Agricultural Research Service. http://www.nal. usda.gov/fnic/foodcomp [accessed Feb 2014].
Wille J, Kydonieus A Palmitoleic acid isomer (C16:1delta6) in human skin sebum is effective against gram-positive bacteria. Skin Pharmacol Appl Skin Physiol. 2003, 16(3):176-87.