North scientists discover genetic variation is to blame for colds

Nov 18 2009 by Helen Rae, The Journal

IF you're suffering from colds and flu that you just can't seem to shake off, your genes may be to blame.

Scientists in the region have discovered that half of women in the UK are at risk from vitamin A deficiency due to a previously undiscovered genetic variation.

Vitamin A plays a pivotal role in strengthening the body’s immune system, protecting against infections such as flu and winter vomiting viruses. It also helps maintain healthy skin and mucus linings such as inside the nose and lungs.

But the Newcastle University team, led by Dr Georg Lietz has shown almost 50% of women have a genetic variation which reduces their ability to produce sufficient amounts of vitamin A from beta-carotene – which is present in many fruits, grains, oils, and vegetables.

In 1987, an American study found excessive use of vitamin A during pregnancy was associated with certain birth defects.

However, beta-carotene was deemed safe and this led to the advice women should eat more of this nutrient, allowing the body to convert what it needs into vitamin A.

But the research of Dr Lietz shows for many women beta-carotene is not an effective substitute.

He said: “Vitamin A is incredibly important, particularly at this time of year when we are all trying to fight off the winter colds and flu.

“It boosts our immune system and reduces the risk of inflammation such as that associated with chest infections.

“What our research shows is many women are simply not getting enough of this vital nutrient because their bodies are not able to convert the beta-carotene.”

Sixty-two women volunteered for the study, of which 29 of them were found to be carrying the genetic variation which prevented them from being able to sufficiently convert beta-carotene into vitamin A. Dr Lietz, who is based in the School of Agriculture, Food and Rural Development at Newcastle University, added: “Worryingly, younger women are at particular risk. 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.”

The research team is now going to study whether the effect of the genetic variation can also be observed in men and whether body composition will influence the ability to absorb and convert beta-carotene into vitamin A.

The team is looking to recruit volunteers to take part in the next stage of the study, seeking healthy, non-smoking men and women aged between 18 and 45 to take part in the study which lasts two weeks. Anyone interested in taking part should contact Dr Anthony Oxley on (0191) 222 5294 or email anthony.oxley@ncl.ac.uk