Increasing trend of spina bifida and decreasing birth weight in relation to declining body-mass index of young women in Japan.

We analyzed the existing data from various surveys on the prevalence of spina bifida, birth weight, and body-mass index (BMI), dietary intake, and smoking habits of Japanese young women. We found that the increasing trend of the prevalence of spina bifida paralleled with the decrease in birth weight, and the decrease in BMI and dietary energy intake and the increase in smoking rate among women of childbearing age. The decreased energy intake is likely due to their distorted self-body image. Based on these findings, we hypothesize that lowering BMI in young women led to increasing prevalence of spina bifida and smaller babies in Japan. This low dietary intake possibly leads to poor folate nutritional status, a risk factor for the development of spina bifida, and increased smoking potentially accelerates these undesirable outcomes. Our hypothesis can be tested using two simultaneous approaches. The first step is an extensive educational campaign for young women to stop smoking, have a realistic body image and eat a sufficient balanced diet. Government officials and health-care workers are encouraged to establish an agenda to educate young women with emphasis on the importance of adequate nutrition during the critical period of reproduction. Together with this campaign, the distribution of folic acid tablets for the prevention of spina bifida can be tried in women of childbearing age through local health centers, which have been well established in Japan.