A British food industry body says teenage girls are showing increasing iron deficiency because of high-caffeine energy drinks.

Rising levels of iron deficiency among teenage girls may be linked to an increase in the amount of high-caffeine energy drinks they consume, it has been claimed.

Britain's Health Food Manufacturers' Association warns that caffeine can inhibit the body's uptake of minerals such as iron.

Recent research has shown that around two-fifths of British girls and young women aged 11 to 24 have lower-than-expected iron levels.

Other studies have indicated that one in 10 British teenagers consume as many of five cans of caffeinated energy drinks every week, the HFMA said.

A poll conducted by the association on 10,000 British adults found that most young people do not know that caffeine can restrict a person's intake of iron and other minerals.

"Micro-nutrients are essential for good health and wellbeing, and iron deficiency is a wide-scale issue which shouldn't be ignored - particularly for teenage girls," said HFMA executive director Graham Keen.

"The best solution for most people is to consume key nutrients such as vitamins and minerals via as healthy a diet as possible."

Supplements could provide insurance for those looking to safeguard their nutritional intake, he added.

Copyright AAP 2014