Inner-city apartment living may reduce access to vitamin D

A trend towards increased indoor living, and the growing popularity of inner-city apartments, raise issues about potential vitamin D deficiency through reduced access to sunlight, University of Otago biochemist Associate Prof Tony Merriman says.

A recent Sunday Star Times article highlighted national concerns that inner-city apartment living, with children playing mainly indoors, could cause a rise in the number who were vitamin D deficient.

The principal of one Auckland school said that up to half of its more than 400 pupils lived in apartments and many had little or no access to outside recreational areas.

The most well-known illness resulting from vitamin D deficiency is rickets, a childhood disease marked by stunted growth and ill-formed bones.

Dunedin City Council city development manager Dr Anna Johnson said yesterday there was also a trend in Dunedin towards increased inner-city apartment living, but relatively few children were living in such apartments.

The cost of transport, and the lengthy commuting times required to reach inner-city jobs from the outlying suburbs, particularly when both parents worked, were drivers for the apartment trend in northern cities. But these were clearly not such significant factors in Dunedin, Dr Johnson said.

Prof Merriman said it was unclear exactly what effect the trend towards inner-city apartment living in Dunedin and elsewhere was having on vitamin D levels.

However, many trends, individually not necessarily of great significance, if combined were likely to result in some people not getting enough vitamin D.

Now, more people worked indoors, rather than in outdoor jobs and vitamin D deficiency was "prevalent as a result of our modern lifestyle". Also, many young people watched television and played computer games rather than playing outdoors.

Vitamin D was a hormone manufactured in the body and one step in its manufacture required "the input of UV-B rays from the sun".