Enriched baby formulas linked to heart disease

New research bolsters the theory that rapid growth in infancy - encouraged by enriched infant formulas - might increase the risk of heart disease and stroke later in life.

The study, published in the Lancet medical journal, found the cholesterol profile was 14 per cent better in adolescents who had been fed breast milk as babies, compared with those fed formula.

The conclusion is the latest to come out of 20 years of research indicating that conditions such as obesity, high blood pressure and diabetes could be influenced by a baby's growth rate.

All those conditions are linked to heart disease.

"These findings considerably strengthen the view that nutrition in the womb and in newborn children has a substantial influence on the risk of coronary heart disease later in life," said Dr Jeremy Pearson, associate medical director of the British Heart Foundation, which was not connected with the research.

He said the study provided very strong evidence that babies fed breast milk rather than formula would grow up to have significantly lower levels of bad cholesterol.

Cholesterol plays a central role in the clogging of arteries, which leads to heart attacks and strokes.

During the investigation, conducted by scientists at the Institute of Child Health in London, 216 pre-term babies born in the 1980s were randomly assigned to two studies while they remained in hospital.

One involved feeding the babies donated breast milk or pre-term formula and the other involved feeding either regular infant formula or pre-term formula, which is enriched with nutrients.

The babies remained in the studies until they weighed 2000 grams or were discharged, which occurred on average four weeks after birth.

The scientists checked the cholesterol levels and other blood profiles involved in heart disease when the children had become teenagers. Among the measures were the ratio of "bad" LDL to "good" HDL cholesterol and the concentrations of c-reactive protein, which rises in the presence of inflammation involved with hardening of the arteries.

Those adolescents who had been given breast milk during infancy had a 14 per cent lower ratio of LDL to HDL cholesterol and lower concentrations of the inflammation protein than those who had been given either types of formula milk in infancy.

"A reduction of LDL cholesterol in the range observed in this study would be expected to lower heart disease risk by about the same amount," said Dr Edward Fisher, American Heart Association spokesman and director of the Lipid Treatment and Research Programme at New York University School of Medicine.

There was no difference in the blood results between the children who were given either pre-term or regular formula.

"The findings ... suggest that infant nutrition permanently affects the [cholesterol] profile later in life, and specifically that breast milk feeding has a beneficial effect," said lead investigator Dr Atul Singhal, of the Institute of Child Health.

Dr Fisher, who was not connected with the study, noted that breast milk has a high amount of saturated fat, so is not considered heart healthy by current understanding. Perhaps breast milk for two years, followed by weaning to reduced fat milk would be a worthy combination, he suggested.

A study conducted in Finland has found no bad effects on growth and development when babies switched from breast milk to reduced fat milk at 2 years of age.

The idea that fast infant growth may be a bad idea seems to contradict current public health recommendations, which strongly support the promotion of infant growth.

However, the scientists said that - at least for pre-term babies - the benefits of slow growth for heart disease and other related disorders would have to be weighed against the danger that slow growth can pose to brain development.

"Promotion of faster growth might prove advantageous overall for infants in developing countries where rapid early weight gain has short-term health benefits," the scientists said.