Old study - new conclusion
Nutrition research is constantly evolving, and I always find it fascinating when old research is re-evaluated through a modern lens.
This wartime study (1944) on 20 conscientious objectors looked at the effect of vitamin C depletion on scar strength. With the food shortages at the time, the goal was to find the minimal amount of vitamin C required to prevent scurvy. From this unique study, it was concluded that 10mg vitamin C daily was required to prevent scurvy. This sort of study would never be allowed to happen today – it depleted vitamin C levels long-term (6 months of supplementation failed to get levels of vitamin C high enough to restore scar strength) and 2 subjects developed heart problems.
Based on the findings, the WHO recommends 45mg a day to prevent scurvy, however revaluation of the data using different statistical methods reveal that 95mg vitamin C is required to prevent weak scar strength for 97.5% of the population. This is more than double the WHO recommendation.
Thankfully, vitamin C is found in a wide variety of fruit and vegetables. Top sources include citrus fruit (53mg in 100g), kiwi (92mg in 100g), peppers (180mg in 100g), strawberries (58mg in 100g), broccoli (89mg in 100g) and potatoes (19mg in 100g). You should be able to get all the vitamin C you need by eating a varied and balanced diet.