South Korea is in dire need of fortification and public education programmes to combat its increasingly severe vitamin D deficiency problem, say researchers at Dongguk University.
While vitamin D deficiency has been getting more attention in many countries, no study so far has reported vitamin D status in Asia.
Researchers at Dongguk University conducted an observational study to explore vitamin D status in South Korea, based on a representative national database obtained from the 2008 — 2014 Korea National Health and Examination Surveys (KNHANES).
The final analyses included a total of 39,759 patients and measured their serum vitamin D levels using radioimmunoassay.
The researchers then reported that the overall mean serum level of vitamin D was 45.7nmol/L in men and 40.9nmol/L in women.
They also noted a ‘significant trend’ of declining serum vitamin D levels of -1.2nmol/L per year in men throughout the course of the survey. In women, the decline was recorded at -0.7nmol/L per year.
In 2008, the overall mean serum vitamin D level was 53nmol/L in men and 45.7nmol/L in women. By 2014, this had fallen to a respective 43.2nmol/L and 39.2nmol/L.
A significant increase in vitamin D deficiency was also noted. Vitamin D deficiency, defined as a serum vitamin D level of below 50nmol/L, was reported in 65.7% of the male patients and 76.7% of the female patients in the overall study population.
These figures were considerably higher than in 2008, when 51.8% of male patients and 68.2% of female patient were vitamin D-deficient.
In 2014, the prevalence had risen to 75.2% and 82.5% respectively.
These patterns have persisted despite medical health professionals having issued warnings about the severity of vitamin D deficiency in the country.
One possible reason for this may be that vitamin D deficiency is seen as problem limited to developing countries.
Indeed, the seriousness of vitamin D deficiency and proposed solutions to the problem have been discussed extensively in India, Palestine and Pakistan, but the issue has also taken root in China, Hong Kong and more recently, South Korea.
What can be done?
The researchers wrote that the current study showed that vitamin D status among South Koreans was continuing to deteriorate, and as such, more extensive and proactive measures should be introduced to help improve vitamin D status in South Korea.
They added that a population-based approach, such as fortification of foods consumed widely by Asians, could serve as a simple yet effective strategy,
However, any such programme would need to match the diversity of dietary culture, so each population would need a programme suited to its tastes.
Government support would also be necessary to help successfully implement the programme.
In conclusion, they wrote: “The present study suggests that mean serum 25 (OH)D level is decreasing and the prevalence of vitamin D deficiency is growing in South Korea.
“Therefore, it is a critical public health issue to improve vitamin D status. A comprehensive campaign and education to raise public awareness of health benefits of vitamin D is necessary.
“There is also a need to develop a vitamin D fortification programme that suits the South Korean population. Vitamin D supplementation or lifestyle modification to increase outdoor activities can be recommended as a useful strategy, for those at risk for vitamin D deficiency.”
“Vitamin D status in South Korean population: Seven-year trend from the KNHANES”
Authors: Ju-Hyun Park, et al.