Vitamin D Supplementation for Bone Health and Prevention of Osteoporosis

Calcium and Vitamin D supplementation nowadays has been considered beneficial for prevention of osteoporosis and subsequent fractures. Osteoporosis is defined as a skeletal disorder characterized by compromised bone strength predisposing a person to an increased risk of fracture. Bone strength primarily reflects the integration of bone density and bone quality. 

The risk of osteoporotic fractures increases with age among individuals aged >50 years. Although many factors contribute to this debilitating event, the most significant causes are reduction in bone mass, structural deterioration, and increased frequency of falls. 

Variation in bone mineral density (BMD) inter-individually is genetically determined by lifestyle factors, including nutrition and exercise which are well established modifiable factors influencing bone mass.

 Low BMD is associated with an increased risk of osteoporotic fracture and maintaining higher BMD in older adults can reduce the fracture risk, which may be achieved by pharmacological and dietary intervention, including the use of calcium and vitamin D supplementation.

It is generally known that vitamin D promotes calcium absorption in the gut and helps to maintain adequate serum calcium concentrations to enable normal mineralization of the bone. Vitamin D is needed for bone growth and bone remodeling by osteoblasts and osteoclasts. Thus, calcium and vitamin D work together synergistically on the bone.

Calcium is needed for our heart, muscles, and nerves to function properly and for blood to clot. Inadequate calcium contributes to the development of osteoporosis because calcium is the dominant mineral in bones. The optimal intake for calcium daily is represented in the table below.

If you have trouble getting enough calcium in your diet, you may need to take calcium supplements. The amount of calcium you will need from a supplement depends on how much calcium you obtain from food or other sources. Calcium supplements are better absorbed when taken in small doses (500 mg or less) several times throughout the day. In many individuals, calcium supplements are better absorbed when taken with food.

Meanwhile, you can get vitamin D in three ways optionally through the skin from sunlight, from the diet, and from supplements. Experts recommend a daily intake of 600 IU (International Units) of vitamin D up to age 70. Men and women over age 70 should increase their uptake to 800 IU daily, which also can be obtained from supplements or vitamin D-rich foods such as egg yolks, saltwater fish, liver, and fortified milk. The Institute of Medicine recommends no more than 4,000 IU per day for adults.

In conclusion, combined calcium plus vitamin D supplementation is statistically significantly associated with reduced total and hip fractures across various populations and generally is effective for increasing bone health. Collectively, decreased risks for hip fractures were stronger in magnitude, and results were more homogeneous compared with total fractures, but consistent decreased risks were observed for both fracture outcomes. Based on the analysis of several researches, it indicates that supplementation could decrease the risk of total and hip fractures by 15 and 30%, respectively, which could decrease the public health burden of osteoporotic fractures.

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