Vitamin D deficiency linked to increased mortality risk

Research involving data from the UK Biobank suggests a link between significant vitamin D deficiency and increased mortality risk. A large-scale study of over 307,000 participants observed over 14 years found that mortality risk decreased as 25(OH)D concentrations increased, particularly for individuals with low levels, up to a threshold of approximately 50 nmol/l.

While vitamin D is essential for bone health and immune function, dietary intake typically only accounts for about 20 percent of total requirements. The remainder is primarily synthesized through the skin via sunlight. Key dietary sources include fatty fish such as eel, salmon, herring, and mackerel, as well as egg yolks and dairy products.

Experts advise against indiscriminate supplementation, recommending that individuals check for specific deficiencies first. Other vitamins, such as B12 and A, also play critical roles in nervous system health and general well-being, though their deficiency symptoms may be subtle and non-specific, such as fatigue or reduced concentration.