The genetically-engineered carrot provides 41% more calcium than a normal carrot and they hope that the addition of the vegetable to a normal diet could help prevent the debilitating bone conditions.

According to Professor Kendal Hirschi at the Baylor College of Medicine in Texas, the carrots were grown in carefully monitored and controlled environments at Texas A&M AgriLife's Vegetable and Fruit Improvement Center.

The research team say those who ate the carrot had a two-fold increase in calcium absorption.

However they say the calcium enriched vegetable needs more research and many safety trials before it will be available to consumers.

The scientists hope their carrot could ultimately offer a healthier way of consuming sufficient quantities of calcium of which the primary dietary source is dairy foods.

However many people for one reason or another have been advised to avoid consuming too much dairy foods.

By tinkering with a gene in the researchers created a carrot which allows calcium to cross more easily over the plant membranes.

Calcium is the most abundant mineral in the human body and more than 99% of total body calcium is stored in the bones and teeth, the rest is found throughout the body in blood, muscle, and the fluid between cells.

Calcium is needed for muscle contraction, blood vessel contraction and expansion, the secretion of hormones and enzymes, and also for sending messages through the nervous system.

On its own, the carrot would not meet the daily requirement of 1,000mg of calcium, but if other vegetables were similarly engineered, intake could be increased dramatically.

Skeptics might be reassured to know that the carrot's orange colour was also the result of 17th Century tinkering by the Dutch who turned a vegetable which was once small, very thin, red, purple into the colour of their national flag.

Scientists are also working on other vegetables and genetic engineering is being used to develop potatoes with more starch and less water so that they absorb less oil when cooked as chips or crisps.

Broccoli too is undergoing a make-over so that it contains more sulforaphane, a chemical which may help protect people from cancer.

The research is published in the Proceedings of the National Academy of Sciences.