Nutrient

Vitamin C

Established research area

A water-soluble antioxidant vitamin needed for collagen formation. Commonly discussed with skin and general resilience.

Often discussed in relation to

Commonly noted

Commonly noted: Vitamin C (ascorbic acid) is an antioxidant that helps protect cells from free-radical damage and is used by the body to make collagen; the body cannot make or store it, so it comes from the diet.
Low intake: Very low vitamin C intake over many weeks is commonly discussed in relation to fatigue, gum inflammation, and slow wound repair (historically known as scurvy).
Higher intake: Very high vitamin C from supplements is commonly discussed in relation to diarrhea, nausea, and stomach cramps; the commonly cited upper intake level for adults is 2,000 mg a day.

Source: NIH ODS

Reference intakes

General reference figures for a typical adult — not a personal target or a claim of need.