A review of a 1944 study, using modern statistical techniques, has led researchers to challenge the World Health Organization’s recommendation for the daily requirement of vitamin C.

77 years ago, the Sorby Research Institute in Sheffield conducted a medical experiment to assess the minimum amount of vitamin C needed to prevent scurvy.

The need to be conservative with the supply of vitamin C was due to an inadequate amount available because of World War II and subsequent food shortages.

Vitamin C is an integral element for the body to create collagen, a component of collagen protein, which creates scars and heals wounds. Collagen also maintains blood vessel walls which helps prevent strokes or heart disease.

Philippe Hujoel, the lead author of the new study on the Sorby vitamin C experiment, 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.”

The experiment comprised of 20 participants who were given either zero, 10, or 70 milligrams of vitamin C daily for, on average, nine months. They were then “repleted and saturated” with vitamin C.

Experimental wounds were given to the participants throughout the study to evaluate sufficient vitamin C levels since the poor healing of wounds can indicate scurvy.

It was concluded that 10 milligrams daily was sufficient to prevent symptoms of scurvy. The WHO used these findings to recommend a healthy daily vitamin C intake of 45 milligrams.

After analysing the findings of the Sorby experiment, Hujoel, who is also a practicing dentist and professor of oral health sciences in the UW School of Dentistry, believes this WHO recommendation is not adequate to avoid weak scar strength.

Hujoel, also an adjunct professor of epidemiology, and Margaux Hujoel, a scientist with Brigham and Women’s Hospital/Harvard Medical School, reviewed the data and put it through modern statistical techniques which were not available to scientists in 1944. The results were published in the American Journal of Clinical Nutrition.

The Hujoel’s stated: “It is concluded that the failure to re-evaluate the data of a landmark trial with novel statistical methods as they became available may have led to a misleading narrative on the vitamin C needs for the prevention and treatment of collagen-related pathologies.

“Robust parametric analyses of the (Sorby) trial data reveal that an average daily vitamin C intake of 95 mg is required to prevent weak scar strength for 97.5% of the population. Such a vitamin C intake is more than double the daily 45 mg vitamin C intake recommended by the WHO but is consistent with the writing panels for the National Academy of Medicine and (other) countries.”

This re-evaluation also concluded that an extensive amount of time and high levels of vitamin C was needed during recovery from vitamin C deficiency.

The Hujoels’ concluded that over 90 milligrams of vitamin C per day for six months was needed for the depleted participants to gain normal scar strength again.

Although the vitamin C depletion caused life-threatening heart issues for two of the Sorby experiment participants, no participants suffered from permanent damage and some stated that they would take part again due to the studies importance.

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