Many women and children in Vietnam have a vitamin D or calcium insufficiency or deficiency. Unknown until know, this is a public health issue whose magnitude has just been discovered by researchers at the IRD and the National Nutrition Institute of Hanoi. By request from the Vietnamese Ministry of Health, the researchers conducted a national study covering a representative sample of women and children. Their investigation shows that the women and children in the sample consume only 1% of the recommended daily allowance of vitamin D and just over 40% of the recommended daily allowance of calcium. These deficiencies have consequences for bone development in young children and can cause rickets. In adults, they are factors in chronic diseases such as osteoporosis and cardiovascular diseases. These results support the urgency of implementing preventive strategies.
A public health problem discovered
Until now, there were very few data in Vietnam on the magnitude of calcium and vitamin D deficiencies. To remedy the problem, the research team analysed blood samples from 600 women and more than 500 children under the age of five, residing throughout the country. This national study showed that approximately 57% of Vietnamese women have a vitamin D deficiency or insufficiency (respectively 17% and 40%), with similar rates among children. Concerning calcium, 14% of women showed a moderate insufficiency, and nearly all participants in the study, children in particular, suffer from slight calcium insufficiency. Such high prevalence, comparable to some other countries in the sub-region, is seen in both urban and rural areas, across all ages, regardless of socio-economic status.
Daily needs not met
On the one hand, as in many Asian countries, Vietnamese women take radical measures to avoid any sun exposure, which helps synthesize a large part of required vitamin D. On the other hand, surveys of food habits conducted in parallel with the blood analyses show that women and children have too little diversity in their diets, in particular low levels of oily fish: they consume only 1% of the daily allowance of vitamin D recommended by the World Health Organisation (WHO). Concerning calcium, the study showed that the quantity consumed is less than half of the daily requirement.
A bad combination for bones
Among women, vitamin D and calcium insufficiencies increase the risks of various chronic disorders, bone fractures and osteoporosis. A previous study recently showed a high prevalence (30 to 45%) of osteoporosis among Vietnamese women over the age of 50, which is clarified by these new results. Among children, the lack of these nutrients could lead to growth retardation and rickets.
Showing the magnitude of the phenomenon in Vietnam, this study will help health authorities to take the necessary measures to prevent these disorders, including the enrichment of foods with vitamin D and calcium (edible oils, special products for children and women), as well as access to a greater diversity of available foods, in particular those rich in bioavailable micro-nutrients.
National Nutrition Institute of Hanoi