Vitamin K, technically known as phytonadione, is a fat-soluble
vitamin manufactured in the liver that is necessary to
ensure proper blood clotting. Its relation to the circulatory
system has been parlayed into its use as a cosmetic ingredient
to help diminish vascular conditions that emerge as skin
imperfections such as dark circles under the eyes, redness
from rosacea, and broken capillaries (including spider
veins, also known as telangiectasia). It is important
to note that vitamin K in skin-care products is considered
a cosmetic ingredient, not a pharmaceutical or drug. Therefore,
cosmetics companies are not required to prove their claims
about what they say it can do for skin.
A typical claim for this vitamin, when applied topically,
is that it can improve the appearance of dark circles
under the eyes. A study published in the Journal of Cosmetic
Dermatology (April 2004, page 73) examined the effect
of applying a gel containing 2% vitamin K plus 0.1% retinol,
vitamin E, and vitamin C. Fifty-seven adults with dark
circles participated in this 8-week study and the results,
while not a slam-dunk, weren't exactly discouraging either:
47% of the testers noted "fair to moderate"
improvement in their dark circles. The majority of testers
noticed no change, but the treatment was well-tolerated.
As encouraging as this sounds whether or not the results
were from the vitamin K or the other vitamins is unknown.
It also doesn't explain if the results were due to the
impact of the antioxidants on skin or vitamin K' effect
on circulation when taken orally.
A smaller-scale study showed that topical application
of a cream with at least 1% vitamin K (other strengths
were used too) shortened the amount of time skin is reddish-purple
after a pulsed dye laser treatment, indicating that when
used in appropriate amounts, vitamin K exerts an anti-inflammatory
effect on skin (Source: Dermatologic Surgery, December
1999, page 942). Again, it would have been more intriguing
if this study examined other topical agents as a means
to reduce post-laser discoloration. Since the study only
included vitamin K, we don't know if a topical vitamin
C product would have had similar benefits, not to mention
green tea, alpha lipoic acid, superoxide dismutase, licorice
extract, or curcumin (all well-documented topical anti-inflammatory
agents). In the larger study mentioned above, I'm curious
as to what the results would have been if the vitamin
K gel was used under one eye and another "cosmeceutical"-type
ingredient was used on the other.
Although not a breakthrough, there is no denying some
effectiveness was found—but you have to find the right
product. Almost no cosmetic companies are selling products
with vitamin K in nearly the amounts used in these studies.
The Peter Thomas Roth line sells two pricey products with
scant amounts of vitamin K, so even a minor benefit to
skin, if at all possible, is unlikely with this miniscule
amount. If you’re curious to try a topical product with
more than a dusting of vitamin K, consider Donnel Super
Skin K-Derm Cream ($50 for 2.5 ounces). Keep in mind that
the studies did not look at vitamin K alone, but if you
were curious if a good amount of vitamin K could make
a difference, this product at least includes enough to
prove that conjecture decidedly for yourself.
What is truly lacking is any research concerning vitamin
K' effectiveness when used topically, at least in terms
of affecting surface capillaries. According to Dr. Craig
Feied, MD, director of the American Vein Institute and
Associate Clinical Professor of Emergency Medicine at
George Washington University, vitamin K is associated
with veins and blood because it is a factor in the blood'
ability to clot. Blood clots can choke off the blood flow
through a vein or capillary and make it disappear. However,
applying vitamin K to the surface of the skin won't make
spider veins disappear, or even fade significantly. If
vitamin K could penetrate the skin to affect the blood
flow in spider veins, it could also affect the blood flow
in healthy veins. If you're considering a vitamin K product
for the reasons mentioned above, this is not cause for
alarm. In order for vitamin K to form blood clots you
need to take large doses that are metabolized in the liver,
where proteins are formed. These special proteins are
what cause the blood to clot, and aren't related to topical
application of vitamin K. Be aware that sunburns, heat,
pressure on the face, injury, smoking, or repeated irritation
or inflammation from irritating skin-care ingredients
can increase the occurrence of spider veins. Avoid these
and you can reduce the appearance of these veins, as well
as their formation. The best treatment option for spider
veins remains non-ablative lasers such as the Intense
Pulsed Light system (Sources: Dermatologic Surgery, October
2005, pages 1,285-1,289; and British Journal of Plastic
Surgery, October 2005, pages 981-987).