|Infants and toddlers should take vitamin D supplements in order to prevent rickets, doctors have advised.
Latest research shows that four in ten infants have low levels
of vitamin D, while 12 per cent have a deficiency which could result in the bone-weakening disease.
A third of the infants who had the deficiency showed evidence of bone mineral loss.
Breastfed babies who did not take vitamin D and toddlers who drank less milk were at a higher risk of developing the deficiency.
The study, conducted by Children's Hospital Boston, was carried out on nearly 400 healthy children who visited a primary care centre for a physical examination between 2005 and 2007. Parents filled out a questionnaire regarding their nutritional intake and that of their children, and also reported on the use of vitamin D and other supplements, time spent outdoors, socioeconomic status and education level.
Dr Catherine Gordon, one of the authors of the study, said: "Given the potential benefits of vitamin D on bone and other tissues
the current findings support recommendations advocating for vitamin D supplementation for all young children."
Recently, there have been several reports of vitamin D deficiency and rickets across the US. Vitamin D deficiency also appears to be high in other countries, including Greece, China, Canada and England.
Full-blown rickets leads to stunted growth, physical deformities, poor teeth, and general ill-health.