Some vitamin C has an affinity for cartilage, chronic knee problems have been treated by naturopaths with 1,000mg of vitamin C every hour for a day, reducing to once every two hours on the second day, and every three hours on the third day. From then on, the intake is kept at 1,000mg daily. The best source is pure orange juice with all meals, which has the added advantage of containing potassium which we lose via sweat. Lose too much, and you can get heart failure. Some 4,000 papers have been written about this mineral in the last 10 years.
Runners lose a lot in sweat.
It has a great influence on immune responses and muscular strength. Excessive tea and coffee drinking cause iron and zinc depletion. White spots on finger nails. Poor hair condition. Zinc plays a vital role in iron absorption, so anaemia needs to be regarded as an iron and possibly zinc deficiency.