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Vitamin A
Science News
Vitamin A Helps Reduce Wrinkles Associated With Natural
Skin Aging
ScienceDaily (May 22, 2007) - Applying vitamin A to
the skin appears to improve the wrinkles associated
with natural aging and may help to promote the production
of skin-building compounds, according to a new report.
The wrinkles and brown spots associated with aging appear
first and most prominently on skin exposed to the sun,
according to background information in the article.
"Human skin not exposed to the sun also ages but
less dramatically," the authors write. "In
intrinsic, natural or chronological aging, skin loses
its youthful appearance by becoming thinner, laxer and
more finely wrinkled. These changes are readily appreciated
by inspecting the upper inner arm." Thinner skin
results from a reduced production of the protein collagen
and may slow wound healing, presenting a public health
issue. "Safe and effective therapies to reverse
the atrophy of natural skin aging do not exist currently,"
the authors note.
Reza Kafi, M.D., then of the University of Michigan
Medical School, Ann Arbor, and now of Stanford Medical
School, Palo Alto, Calif., and colleagues assessed the
effectiveness of vitamin A (retinol) lotion in 36 elderly
individuals (average age 87 years). Researchers applied
a lotion containing 0.4 percent retinol to participants'
right or left upper inner arms, and lotion with no retinol
to the other arm, up to three times a week for 24 weeks.
Wrinkles, roughness and overall severity of aging were
each graded on a scale from zero (none) to nine (severe)
before treatment and two, four, eight, 16 and 24 weeks
after beginning treatment. In addition, 4-millimeter
biopsy specimens of skin were taken from both arms at
the beginning and end of the 24-week treatment period.
A total of 23 individuals completed the full study
and 13 withdrew from the study prior to completion.
When the researchers included the individuals who had
dropped out of the study by assuming their skin did
not change after their last measurement, wrinkles, roughness
and overall aging severity were all significantly reduced
in the retinol-treated arm compared with the control
arm. The skin biopsies revealed that the retinol increased
the production of glycosaminoglycan and procollagen,
structural components of the skin.
"Topical retinol improves fine wrinkles associated
with natural aging," the authors conclude. "Significant
induction of glycosaminoglycan, which is known to retain
substantial water, and increased collagen production
are most likely responsible for wrinkle effacement [reduction].
With greater skin matrix synthesis [production of compounds
that form new skin], retinol-treated aged skin is more
likely to withstand skin injury and ulcer formation
along with improved appearance."
The research is described in the May issue of Archives
of Dermatology, one of the JAMA/Archives journals. (Arch
Dermatol. 2007;143:606-612)
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