Sugar
The body requires sodium for its operation, but too much of it can cause high blood pressure and contribute to heart attacks, strokes, and kidney disease. Salt can also cause calcium loss and osteoporosis. The salt can cause cellular inflammation, which is what causes joints to hurt.
Stop eating highly salted processed foods and fried foods. Stop adding salt to your foods. You will need to adjust to eating less salty, but you will feel healthier in the end.