Children and teenagers who were exclusively breastfed for at least part of their infancy apparently have lower blood pressure than their formula-fed peers, according to a new study.

An international research team found that among nearly over two thousand 9- to 15-year-olds, those who were ever exclusively breastfed had slightly lower blood pressure than those who were never reared solely on breast milk.

The magnitude of the effect, according to the study authors, is similar to the benefits seen when adults use exercise or salt restriction to lower their blood pressure.

The researchers, led by Dr. Debbie A. Lawlor of the University of Bristol in the UK, report the findings in the Archives of Disease in Childhood.

The benefits of breastfeeding are well documented and range from easier digestion to a lower risk of childhood illnesses such as diarrhea, ear infections and pneumonia. Whether breast feeding results in lower blood pressure later in life has been less clear, but one large study has suggested as much.

Breastfeeding Information
The breasts get ready to make milk during pregnancy. Milk production is controlled by hormonal signals in the body.

Successful breastfeeding depends in part on the mother’s confidence in her ability to breastfeed. This involves having the proper environment to nurse and being prepared emotionally and physically for the experience. If the mother is pain free, relaxed and supported by family and others, success is more likely. Proper nipple care, positioning and nursing frequency may help to prevent some common breastfeeding problems.

The new findings, based on 2,192 children and teenagers from Estonia and Denmark, firm up the evidence of a blood pressure benefit, according to Lawlor and her colleagues.

“The likely beneficial effects on future blood pressure” can be added to the list of health advantages attributed to breastfeeding, the researchers conclude in their report.

Children in the study underwent physical exams and blood tests to measure their levels of cholesterol and the sugar-regulating hormone insulin. Together with high blood pressure and abdominal obesity, abnormal cholesterol and insulin levels constitute a condition called metabolic syndrome, which can eventually lead to Type 2 diabetes, Heart disease or Stroke.

Mothers were asked whether they ever exclusively breastfed their children.

Overall, Lawlor’s team found, children who were ever raised solely on breast milk had slightly lower systolic blood pressure - the first number in a blood pressure reading, which reflects blood pressure while the heart is contracting. When other factors, such as weight, age and family income, were considered, exclusive breastfeeding was linked to an average two-point reduction in systolic blood pressure.

The longer children were exclusively breastfed, the more marked was the effect on blood pressure, according to the researchers. This “dose-response” relationship, they note, gives weight to the idea that breastfeeding indeed led to the lower blood pressure.

Breastfeeding was not, however, related to any of the other conditions that make up metabolic syndrome.

Exactly how breast milk may influence blood pressure later in life is not fully clear. It may, Lawlor and her colleagues note, have to do with hormonal effects or the lower sodium content in breast milk compared with formula. In addition, breast milk contains certain fatty acids, not found in many infant formulas, that research suggests may affect children’s blood pressure.

SOURCE: Archives of Disease in Childhood, June 2005.