Tiny improvements in the health of the unborn child could dramatically cut rates of killers such as diabetes and heart disease, says a leading UK scientist.

And babies born small who then feed well and swiftly catch up their peers may be at much greater risk.

Professor David Barker, from the Medical Research Council at Southampton University, giving a lecture at the European Society for Human Reproduction and Embryology on Monday, said it was time to take a fresh look at ways of cutting the death toll from these illnesses.

If one could optimise early growth, one could greatly reduce the burden of chronic disease on society

Professor David Barker

He endorsed the theory that the way the foetus reacts to diet is programmed in the womb by the nutrients which are available or unavailable there.

Many other doctors, he said, focused too closely on smoking, adult diet and the possibility that genes, hitherto undiscovered, may play a significant role.

The shape of the baby at birth � influenced by the environment of the womb, may be a key marker of future risk of heart disease, he said.

A recent study by Professor Barker suggested that thin new-borns whose growth then accelerated to catch up normal babies had the highest risk.

Western diet

Professor Barker told the conference: "A picture is now emerging of why the epidemic of coronary heart disease may have been triggered by the high energy Western diet."

He suggested that it might be possible to as much as halve the risk of coronary heart disease in men if maternal diet could be improved.

"If one could optimise early growth, one could greatly reduce the burden of chronic disease on society."

Well over 100,000 people die from heart disease in the UK each year, and the complications of type II diabetes, another illness linked to foetal programming in the womb, are responsible for thousands of these.

Professor Barker told the conference: "We need to be thinking about changing the body composition and diets of young women and preventing imbalances between pre and postnatal growth among today�s children if we want to reduce the toll from coronary heart disease and other chronic life-threatening conditions."