Joanna Whitehead wrote this article in The Independent:

The recommended dose of vitamin C should be doubled, according to a recent study.

Scientists behind the claim have described the methods behind the 1944 study that continues to inform current day levels as "shocking".

At present, the NHS and World Health Organisation (WHO) recommend a daily intake of the vitamin of 40mg and 45mg respectively.

However, academics behind a new study published in the American Journal of Clinical Nutrition have said that the research conducted by The Sorby Research Institute was to assess the nutrition levels of Britons during World War II when food was in short supply.

At this time, the aim was to avoid scurvy, rather than maximising health, they claim.

Lead professor Philippe Hujoel said: "The vitamin C experiment is a shocking study.

"They depleted people's vitamin C levels long-term and created life-threatening emergencies. It would never fly now."

As part of the study, participants were assigned zero, 10 or 70 milligrams of vitamin C per day for an average of nine months.

Experimental wounds were inflicted on participants during this period, with researchers using the "scar strength" as a measure of adequate vitamin C, since poor wound healing is is an indicator of scurvy.

Prof Hujoel added: "The findings of the re-analyses of the Sorby data suggest that the WHO's recommendation is too low to prevent weak scar strength.

"Such a vitamin C intake is more than double the daily 45mg vitamin C intake recommended by the WHO but is consistent with the writing panels for the National Academy of Medicine and (other) countries."

According to the NHS, vitamin C - which is also known as ascorbic acid - has three major functions.

These include helping to protect cells and keeping them healthy, maintaining healthy skin, blood vessels, bones and cartilage, and helping with wound healing.

Good sources of vitamin C include citrus fruit, such as oranges, peppers, Brussels sprouts, potatoes, kimchi, strawberries, blackcurrants and broccoli.

A Department for Health and Social Care (DHSC) spokesperson told The Independent: "The government's independent expert advisers on nutrition regularly review new evidence that may indicate existing recommendations need to be considered, but they do not consider it necessary to review Vitamin C recommendations at this time."