A study published last month in The Lancet Diabetes & Endocrinology journal concluded low levels of vitamin D were a result, rather than a cause, of ill-health.
The latest study, led by Dr Mark Bolland from the university's Department of Medicine, analysed comparisons of individuals who took calcium with their vitamin D supplements and those who didn't. Calcium is essential for healthy bones and teeth.
Some of Bolland's research indicates an increased risk of hip fractures with vitamin D supplementation.
It follows studies that showed vitamin D supplements made no difference in preventing osteoporosis in most healthy adults.
Arapera Salter took supplements two years ago when she had low vitamin D levels and she stands by the decision.
A prescription from her family doctor for three high-dose supplements, taken once a month, cost $5.
The 32-year-old paediatric registrar, who had her first child five weeks ago, wanted her vitamin D levels right before getting pregnant.
"I wanted to have good levels before I was pregnant because if you've got low vitamin D then your baby will get low vitamin D."
Salter said she intended to have her vitamin D levels retested once she stopped breastfeeding and, if needed, begin taking the supplements again.
"I definitely don't feel like I've wasted my money.
"Even though [the research] doesn't show that it prevents fractures, it's something that is down the line, like when you've got frail bones. I would rather try to prevent her [daughter Aniwa] from having that."
Salter lives in Dunedin with partner Tom Wolfenden and their daughter.
In New Zealand, about 12 per cent of people aged over 50 - 5 per cent of the population - receive state-funded vitamin D supplements. This figure does not include over-the-counter purchases.
In residential care facilities, 74 per cent of elderly residents are given the supplements, which are even more prevalent in the US.
