November 24, 2009

New factor for vitamin A deficiency discovered

In a presentation at the 2nd Hohenheim Nutrition Conference this month in Stuttgart, Germany, Dr Georg Lietz of England's Newcastle University reported that many women in the UK could be at risk of vitamin A deficiency due to genetic variation.

Vitamin A's fat soluble property means that the vitamin can accumulate in the body. Concerns regarding potential toxicity have led to the suggestion that much of our vitamin A requirement could be met by consuming beta-carotene, which converts to vitamin A when needed.

Dr Lietz and his colleagues examined the gene that encodes an enzyme known as beta-carotene 15,15'-monoxygenase (BCMO1) in 62 female volunteers. The enzyme is responsible for the conversion of beta-carotene into vitamin A, a process that varies in up to 45 percent of healthy individuals. The team found that 47 percent of the women had a genetic variation that reduced their ability to convert beta-carotene.

"Vitamin A is incredibly important � particularly at this time of year when we are all trying to fight off the winter colds and flu," noted Dr Lietz, who is affiliated with Newcastle University's School of Agriculture, Food and Rural Development. "It boosts our immune system and reduces the risk of inflammation such as that associated with chest infections. What our research shows is that many women are simply not getting enough of this vital nutrient because their bodies are not able to convert the beta-carotene."

"Worryingly, younger women are at particular risk," Dr Lietz added. "The older generations tend to eat more eggs, milk and liver which are naturally rich in vitamin A whereas the health-conscious youngsters on low-fat diets are relying heavily on the beta-carotene form of the nutrient."

Dr Lietz and his associates' research was described earlier this year in the Federated Association of Societies for Experimental Biology (FASEB) Journal. The scientists plan to assess whether body composition also affects the ability to convert beta-carotene into vitamin A.