What is the degenerative disease characterized by pain and swelling in the joints?

Bone density is actually HIGHER rather than LOWER in osteoarthritis. Low bone density is the telltale sign of osteoporosis, a skeletal disorder characterized by weakened bones due to excessive loss of bone mass.

Osteoarthritis, on the other hand, is characterized by increased bone density and bony growths (osteophytes) in conjunction with articular cartilage degeneration.

Osteoporosis and osteoarthritis are two different diseases with opposite bone density problems

Calcium intake is not directly associated with the onset of osteoarthritis. Vitamins A, C and E, the major antioxidants, have been identified as having a potential for protecting cartilage and connective tissue from oxygen radical damage. Vitamin D may also play an important role in osteoarthritis by way of bone mineralization and cell differentiation. Good dietary practices may help protect individuals against osteoarthritis to some extent.