Если есть проблемы с костями или сухожилиями (и даже если их нет), то рекоммендуют следующие витамины/suppliments:

- Кальций (женщинам вообще без него нельзя, мужчинам на протеиновой диете - тоже )
- MSM
- Глюкозамин

Вот описание глюкозамина на английском языке.

Glucosamine is composed of glucose (a sugar) and glutamine (an amino acid). It is utilized by chondrocytes to form glycosaminoglycans (GSG) and proteoglycans (PG). Both of these constituents attract and bind water into cartilage, increasing resiliency. Research indicates that glucosamine may actually help your body repair damaged or eroded cartilage. A number of studies have been conducted on glucosamine sulfate and glucosamine hydrochloride, with a preponderance of positive results. Glucosamine sulfate is considered the more effective of the two. One study from the University of Liege in Liege, Belgium studied the effects of glucosamine sulfate on 212 patients with knee osteoarthritis. Participants took either 1,500 mg glucosamine or a placebo once daily for three years. The study compared joint-space width at enrollment, one year, and at the study's conclusion. The 106 patients on placebo had a progressive joint-space narrowing, while participants taking glucosamine experienced no significant joint-space loss, indicating glucosamine may beneficially modify cartilage structure