Vitamin D deficiency is highly prevalent among aging populations and represents a significant public health concern. In older adults, insufficient vitamin D status contributes to skeletal complications and may influence a range of extra-skeletal health outcomes, underscoring the need for targeted prevention and management strategies.

Why Vitamin D Matters in Older Adults

Vitamin D deficiency in older adults is associated with:

• Bone fragility and increased fracture risk

• Falls and muscle weakness

• Elevated risk of type 2 diabetes, cardiovascular disease, respiratory infections, and cognitive decline

Aging populations are at higher risk due to reduced skin synthesis, altered renal metabolism, limited sun exposure, increased adiposity, and higher rates of institutionalization.

Consensus guidelines recommend maintaining serum 25-hydroxyvitamin D [25(OH)D] levels above 50 nmol/L to prevent skeletal and selected extra-skeletal complications.

Age-Related Decline in Vitamin D Production

Vitamin D production declines by approximately 13% per decade, with endogenous synthesis by age 70 reduced to roughly half of that at age 20. Institutionalized older adults rarely meet vitamin D requirements through sun exposure alone.

Skeletal Consequences

Vitamin D supplementation combined with calcium has been shown to reduce hip fracture risk by up to 43%. Severe deficiency (25[OH]D < 30 nmol/L) is associated with osteomalacia, low bone mineral density, secondary hyperparathyroidism, and increased fracture risk.

Falls, Frailty, and Dosing Considerations

Daily low-dose vitamin D supplementation (700–1,000 IU) is associated with reduced fall risk, whereas high intermittent bolus dosing may increase fall risk and should be avoided.

Beyond Skeletal Health

Vitamin D may support cardiovascular, metabolic, cognitive, and immune health, particularly in deficient individuals, although the strength of evidence varies across conditions.

Prevention Strategies in Older Adults

Preventive approaches include:

• Sunlight exposure: Physiological but limited by cancer risk, mobility, latitude, and skin aging

• Food fortification: Broad population reach but subject to regulatory and implementation challenges

• Supplementation: Effective and controllable, though access and adherence remain concerns in low-income and elderly populations

Consensus Recommendations

• Target serum 25(OH)D levels above 50 nmol/L

• Avoid levels below 30 nmol/L in older adults

• Prioritize supplementation for deficient, institutionalized, and high-risk groups

• Avoid high, infrequent bolus dosing regimens

Reference:
doi: 10.1007/s12020-022-03208-3