Vitamin K, vitamin C and linoleic acid are linked to improved elasticity in aging skin, according to the results of two studies.
Recent studies have shown that there is a link between vitamin K deficiency and pseudoxanthoma elasticum (PXE), an inherited condition resulting in severe wrinkling of the skin on the face and body. Past studies also have linked vitamin K intake to an improvement in the elasticity of the skin in subjects with this condition.
Although the link between vitamin K and normal levels of skin wrinkling seen in healthy populations is unknown, scientists suggest that these studies illustrate that the vitamin is involved, in some capacity, in the skin"s elastic qualities.
In both healthy people and people with PXE, the reduction in skin elasticity is due to the calcification of the elastic fibers of the skin. High concentrations of calcium and phosphate in the extracellular space cause calcification, unless inhibited by a family of proteins.
In a recent study published online in the journal Laboratory Investigation, researchers determined that in patients with PXE, Matrix γ-carboxyglutamic acid protein (MGP) is not inhibiting calcium precipitation to an extent capable of improving skin elasticity. This is because the MGP protein must be activated by a vitamin-K dependent enzyme and patients with PXE have a difficult time metabolizing vitamin K.
Other research has shown that individuals who can’t metabolize vitamin K exhibit PXE symptoms, lending further support to vitamin K’s role in the poor skin health of PXE sufferers.
Although the association between vitamin K and skin elasticity in normal subjects without PXE is not known, the study authors suspect that there is a connection. The fact that there is such a strong link between vitamin K and PXE lead the researchers to theorize that the same connection may exist in healthy aging individuals and may be one cause of skin wrinkling and loss of elasticity.
In a second study, another group of scientists investigated the role of vitamin C and linoleic acid intake in skin wrinkling. Linoleic acid is an omega-6 fatty acid and is found in such items as conjugated linoleic acid, a healthy fat found in dairy products and available by supplement form.
The scientists used data from the first National Health and Nutrition Examination Survey (NHANES I) to examine the relationship between dietary nutrient intakes and skin-aging appearance. They also took into account clinical examinations conducted by dermatologists. Skin aging was defined as having a wrinkled appearance, senile dryness (dryness as a result of aging) and skin atrophy (skin thinning). The study included 4,025 females between the ages of 40 and 74.
The researchers found that lower intakes of vitamin C in the diet were significantly associated with the prevalence of wrinkled appearance and senile dryness. The researchers thought this is probably due to the vitamin"s antioxidant properties, its ability to enhance collagen synthesis and its potential ability to protect against sun damage.
The study also found that higher dietary intake of linoleic acid was linked to a reduced chance of developing senile dryness and skin atrophy. Another finding was that higher intakes of fats and carbohydrates were associated with an increased incidence of wrinkled and thinning skin. A 17-gram increase in fat and a 50-gram increase in carbohydrate intake increased the likelihood of both wrinkled appearance and skin atrophy.
The researchers concluded, “Higher intakes of vitamin C and linoleic acid and lower intakes of fats and carbohydrates are associated with better skin-aging appearance.”
References:
Gheduzzi D, Boraldi F, Annovi G, Paolinelli DeVincenzi C, Schurgers L, Vermeer C, Quaglino D, Pasquali Ronchetti I. Matrix Gla protein is involved in elastic fiber calcification in the dermis of pseudoxanthoma elasticum patients. Laboratory Investigation. October 2007. Epub Ahead of Print.
Cosgrove MC, Franco OH, Granger SP, Murray PG, Mayes AE. Dietary nutrient intakes and skin-aging appearance among middle-aged American women. Am J Clin Nutr. 2007 Oct;86(4):1225-31.