A solid nutritional foundation with a multivitamin and mineral formula is necessary. Mineral deficiencies are more common than vitamin deficiencies. Therefore, you may want to look for a multivitamin that features chelated trace minerals.
Silica from the horsetail (Equisetum arvense) plant -studies have shown that silica can increase calcium absorption by 50% and bone density by 15%. I recommend 40 mg of silica and flavonoids that help with absorption, twice daily.
The trace mineral strontium is also necessary for optimal bone health. Studies using strontium in the treatment of osteoporosis showed significant improvements in bone mineral density (BMD). Look for a formula that contains strontium citrate, which is a very absorbable form of strontium. I recommend taking 680 mg of strontium at breakfast time and two hours away from any calcium supplement.