Senior Korean women have much less vitamin D than men (possible reasons)
High prevalence of vitamin D deficiency in adults aged 50 years and older in Gwangju, Korea: the Dong-gu Study.
J Korean Med Sci. 2014 Jan;29(1):149-52. doi: 10.3346/jkms.2014.29.1.149. Epub 2013 Dec 26.
Song HR1, Kweon SS2, Choi JS1, Rhee JA1, Lee YH3, Nam HS4, Jeong SK5, Park KS6, Ryu SY7, Choi SW7, Shin MH1.
Vitamin D plays an important role in bone metabolism and maintaining bone health. Recently, new evidence has revealed that vitamin D affects chronic diseases such as autoimmune diseases, cardiovascular diseases and certain cancers. The aim of this study was to evaluate the vitamin D status and the prevalence of vitamin D deficiency in an urban Korean population. This study included 8,976 participants (3,587 men and 5,389 women) aged 50 yr and older. Serum 25(OH)D level was measured by chemiluminescent microparticle immunoassay. The prevalence of vitamin D deficiency [25(OH)D < 20 ng/mL] was 59.7% and 86.5% in men and women, respectively. The prevalence of vitamin D deficiency increased significantly with age in men, but not in women and it decreased from April to July, more prominently in men than in women. These results suggest that sun exposure, intake of vitamin D supplement, and regular physical activities is recommended in an urban Koreans, especially in women.
Far more senior Korean women are vitamin D deficient (< 20ng) than men of the same age

Senior Korean women do not recharge vitamin D as much as men during summer
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PMID: 24431921
Parasols in Korea and Japan - while the sun is out



See also VitaminDWiki
South Koreans - half take supplements, Vitamin D levels dropping, COVID-19
Obese need 2.5 IU of vitamin D per kg to increase 1 ng (about 3.4 X more) – RCT Sept 2013
Iron deficiency is a cause of Vitamin D deficiency Korea - not senor women
5X more likely to be vitamin D deficient if anemic - Dec 2012 Korea - not senor women
2X increased chance of anemia (low iron) associated with low vitamin D – Sept 2013 Korea - not senor women
Japanese women 20X more likely to be vitamin D deficient than men, etc. – Many 2013
9X increase in Koreans seeking help with vitamin D deficiency in just 4 years – Jan 2015
Women have a higher percentage of body fat than men
women = red dots

- Women around the world want whiter skin has a picture of a Chinese woman at the beach
