Doctors at the University of Bristol have reported that the benefits of breastfeeding could pay off many years later by helping to reduce levels of blood pressure, a factor that contributes to heart attacks in old later life.
A new study of seven-year-old children has shown a difference in their blood pressure according to whether they were breast-fed or bottle-fed as babies. These results suggest that lower blood pressure could be added to the list of known benefits of breastfeeding.
This latest report is based on data collected by the Children of the 90s project, also known as the Avon Longitudinal Study of Parents and Children, based at the University of Bristol. The report study is published in the medical journal Circulation, the journal of the American Heart Association..
Researchers measured the blood pressures of 4,763 children.
On average the children who had been breastfed beyond the age of two months (34 per cent) had about one millimeter of mercury (mm Hg) lower blood pressure at age seven than did children showed a 1.70.9 mm reduction in systolic blood pressure when compared with children who had been brought up exclusively on formula milk.
The longer a child was breastfed, the greater the difference.
Previous research suggests that the benefits could be even more pronounced later in their lives.
Dr Richard Martin from the the University of Bristol’s Department of Social Medicine says that although the difference that was found was quite small, even a small reductionthis could still have important public health implications for the adult population.
It has been calculated that a one per cent reduction in systolic blood pressure across the population could reduce the mortality rate by 1.5 per cent . In the USA and UK that would be equivalent to a reduction in premature mortality of about 10,000 deaths per year among men and women aged 35 to 64.
Dr Martin says: “Around 40 per cent of all infants in the USA or UK are never breastfed in the USA or UK. If breastfeeding promotion initiatives raised breastfeeding rose from 60 to 90 per cent, approximately 3,000 extra deaths a year may be prevented annually among 35 to 64-year-olds in these two countries.”
But he warns that iIf breastfeeding rates dropped from the current 60 per cent to their levels in the 1970s (around 25 per cent) – there would could eventually be a corresponding rise in premature deaths.
Academic paper reference
Martin RM, Ness AR, Gunnell D, Emmett P, Davey Smith G, ALSPAC Study Team. "Does breast feeding in infancy lower blood pressure in childhood?" The Avon Longitudinal Study of Parents and Children. Circulation. doi: 10.1161/01.CIR.0000118468.76447.CE
Notes
- ALSPAC The Avon Longitudinal Study of Parents and Children (also known as Children of the 90s) is a unique ongoing research project based in the University of Bristol. It enrolled 14,000 mothers during pregnancy in 1991-2 and has followed the children and parents in minute detail ever since.
- Exactly why breastfeeding should affect long term blood pressure is unclear. At one stage it was attributed to the high sodium content of formula milk, but the present results were based on modern formula milk whose composition is closer to breast milk. It is known that breast milk contains long chain polyunsaturated fatty acids which may play a role in blood pressure control.