Too many vitamins may actually be bad for you, a new study suggests.

Reseachers report a link between vitamin use and higher death risk in older women. It appears to support what some experts have suspected for some time — that supplements are only beneficial to those with a nutrient deficiency.

The vitamins that seemed to particularly raise mortality rates are those that are most vigourously pushed on the market: multivitamins, folic acid, B6, zinc, iron, copper and magnesium. Researchers now feel that these are being widely bought by consumers without any real evidence that they provide any benefit.

The study involved 38,000 US women and relied upon their recalling what vitamins and supplements they had taken over the previous two decades. Variables to consider, which were difficult to control, were factors such as general health which may have had some influence over the findings.

Despite this, there does at least seem to be enough evidence to say that supplements should only be used when there is a real medical cause for such.

In recent years, the reasons for taking vitamins have shifted from tackling deficiencies to promoting general wellbeing, with people taking them pre-emptively. However, as with having too little, taking too much can also carry its own dangers.

Eating well and maintaining a balanced diet should generally provide a person with the vitamins and minerals they need.