Effects of echinacea: A study of 149 health college students who acquired colds naturally found no differences in the length of the colds or the severity of symptoms between those who took herbal remedy echinacea and those who took a placebo (dummy pill).

Stand up to osteoporosis

Irish women can now assess their own risk of osteoporosis by answering a series of questions formulated by the Irish Osteoporosis Society and discussing any concerns with their GP. The condition involves a progressive thinning of the bones, making them more likely to break. Early detection and treatment of the condition is vital to maintain long-term health. The leaflet, "Osteoporosis: Where Do You Stand?", is available from the IOS at 01 677 4267.

Cot deaths and smoking

A slower arousal response, as a result of tobacco exposure in the womb, might explain the increased risk of cot death (SIDS) among babies of smokers, a new study suggests. Researchers monitored the sleep and arousal patterns of 20 babies between the ages of eight and 12 weeks. Half of the babies' mothers smoked during pregnancy, the other half were non-smokers. Tests, including an aural (hearing) stimulation test, were carried out over 10 to 12 hours of REM (rapid eye movement) and non-REM sleep. The results showed that there were no differences in overall sleep patterns, nor arousal from REM sleep among the two groups of babies. However, five of the babies whose mothers smoked during pregnancy did not respond to the maximum hearing stimulus during non-REM sleep.

What children carry

A US study of school backpack weight and contents found that most parents had no idea how much their children were carrying to school each day. Heavy loads increase the risk of injury and permanent changes in posture and gait. In the US, backpack injuries account for 10,000 hospital/clinic visits every year. Among 745 young children attending primary schools in Texas, 188 routinely carried backpacks weighing at least 10 per cent of their body weight.

Lifelines is compiled by Dr Muiris Houston, Medical Correspondent