Vitamin deficiencies in adults
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Prevalence and Risk Factors of Vitamin Deficiencies in Adults
Vitamin deficiencies, particularly of vitamin D and B vitamins, are common among adults worldwide and are influenced by various demographic, lifestyle, and health factors. Vitamin D deficiency is especially prevalent, with studies showing that 20% of Australian adults and up to 70% of older adults in China are affected, compared to 17% in the United States. Risk factors include limited sun exposure, obesity, certain chronic diseases, older age, and specific lifestyle choices such as low physical activity and smoking. Ethnic minorities and individuals with malabsorption issues are also at higher risk for deficiencies in both vitamin D and B vitamins Malacova2019Wei2019Sechi2016.
Vitamin D Deficiency: Screening, Diagnosis, and Management
Vitamin D is produced through skin exposure to sunlight and obtained from dietary sources. Deficiency is best assessed by measuring blood levels of 25-hydroxyvitamin D. While vitamin D deficiency is widespread, routine screening in asymptomatic adults is not universally recommended due to insufficient evidence of benefit. Instead, targeted testing is advised for those at higher risk, such as individuals with bone, liver, or kidney diseases, obesity, malabsorption syndromes, or those on certain medications Kennel2010LeFevre2015Cesareo2018+1 MORE.
For adults at risk or with confirmed deficiency, supplementation with vitamin D2 or D3 is recommended, with doses tailored to individual needs. Maintenance doses of 800–2000 IU per day are generally advised, with higher initial doses for rapid correction in some cases. Routine monitoring during supplementation is not necessary for most, but may be considered in special populations after several months of treatment Cesareo2018Płudowski2022.
Health Impacts of Vitamin D Deficiency in Adults
Vitamin D deficiency is linked to a range of health issues beyond bone health. In older adults, low vitamin D levels are associated with increased inflammation, impaired immune function, higher risk of respiratory infections (including COVID-19), low mood, and worse cognitive performance. These associations highlight the importance of maintaining adequate vitamin D status, particularly in vulnerable groups such as the elderly, those with chronic illnesses, and individuals with limited sun exposure Wilkins2006McCartney2020Laird2014.
B Vitamin Deficiency: Neurological and At-Risk Populations
B vitamin deficiencies, including B12 and folate, are a leading cause of neurological impairment in adults. At-risk groups include the elderly, people with alcoholism, those with heart failure, individuals who have undergone obesity surgery, and vegetarians or vegans. Multiple B vitamin deficiencies often coexist and can contribute to neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Prompt diagnosis and treatment are crucial to prevent or mitigate neurological symptoms and disability .
Strategies for Prevention and Public Health Recommendations
Given the high prevalence of vitamin D deficiency, public health strategies should focus on promoting safe sun exposure, dietary intake, and supplementation, especially for at-risk groups. Expert consensus recommends increasing awareness and harmonizing guidelines for diagnosis and treatment. For B vitamins, targeted screening and supplementation in high-risk populations are important preventive measures Malacova2019Płudowski2022Sechi2016.
Conclusion
Vitamin deficiencies, particularly of vitamin D and B vitamins, are common in adults and can have significant health consequences, especially for older adults and those with specific risk factors. Targeted screening, individualized supplementation, and public health strategies are essential to address these deficiencies and improve overall health outcomes in adult populations.
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Clinical Practice in the Prevention, Diagnosis and Treatment of Vitamin D Deficiency: A Central and Eastern European Expert Consensus Statement
A daily dose of 800 to 2000 IU of vitamin D is recommended for adults to maintain sufficient levels and treat vitamin D deficiency, with higher doses for rapid correction.
Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults.
Vitamin D deficiency is associated with low mood and impaired cognitive performance in older adults, but not with physical performance.
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