Vitamins
The 1944 Sheffield experiment revealed that 95 mg of vitamin C daily is needed for optimal wound healing—far more than the long-recommended 10–45 mg minimum. The gap between preventing deficiency and achieving optimal levels is significant.
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In 1944, one of the most famous and significant experiments on human subjects took place in Sheffield, England. Food was scarce at the time, so researchers decided to turn necessity into opportunity.
The researchers tested, based on the vitamin C scarcity of that era, what the lowest vitamin C threshold was to prevent the vitamin C deficiency disease scurvy. Twenty test subjects were divided into groups and allowed to consume 0, 10, and 70 mg of vitamin C daily for nine months.
Just a few years earlier, in 1933, the famous researcher and later Nobel Prize winner Albert Szent-Györgyi discovered that the then-mysterious seafarer's disease scurvy could be prevented with vitamin C, which he had discovered in 1926.
By that time, scurvy had been known for almost 2,000 years. Even during the age of exploration, beginning around 1500, many sailors regularly died from scurvy—historical records show that Indigenous Canadians had already developed a "remedy" for scurvy at that time (vitamin C-rich plant parts).
Five hundred years later, in England 1944, research would reveal what dose was necessary to prevent scurvy. During this extreme experiment—one that would not be permitted today—some subjects became dangerously ill, though fortunately there were no lasting effects.
Beyond extreme fatigue and exhaustion, inflammation, muscle wasting, and increased susceptibility to infection, collagen formation disorders are a hallmark of vitamin C deficiency. Without vitamin C, collagen cannot be formed.
This is why typical scurvy symptoms include excessive gum bleeding (mouth rot), but also impaired wound healing. This is exactly how the subjects were examined. The researchers created wounds in the subjects and analyzed scar strength.
With the conclusion at the time: 10 mg of vitamin C is needed at minimum to prevent this severe deficiency disease. Based on these findings, the WHO set a minimum vitamin C intake recommendation of 45 mg.
In 2021, a reanalysis of the historical data was published in the renowned journal The American Journal of Clinical Nutrition. In their "detective work," researchers applied modern data analysis methods that did not exist at the time.
With the result:
"Robust parametric analyses of the historical data show that an average daily vitamin C intake of 95 mg is required to prevent weak scar strength in 97.5% of the population."
The doses required for normal scar healing in most people are far higher than the minimum doses required for wound healing itself.
Additionally, the new analysis showed that restoring normal vitamin C levels after prolonged deficiency requires high vitamin C doses. In fact, even 90 mg of vitamin C over a period of six months could not restore normal scar strength.
Let us state it clearly: many people always look downward. "How much is needed to reach a minimum threshold that prevents the emergency?" Even the WHO writes in current work on vitamin C that preventing extreme deficiency has nothing to do with optimal intake.
What exactly optimal vitamin C intake might be is suggested not just by this new study—in our new blog article we briefly address the question of which vitamin C intake is sufficient to saturate vitamin C levels.
As always, good to know!
