1On World Metrology Day on May 20th, 875, 17 countries signed the Metric Convention in Paris, France, which is an intergovernmental agreement to adopt the international system of units worldwide and ensure the consistency of measurement results. /kloc-for more than 0/00 years, the international metrology convention has played a great role in ensuring the unification of international metrology standards, promoting international trade and accelerating the development of science and technology. From 65438 to 0999, the 2nd1International Metrology Conference designated May 20th of each year as "World Metrology Day".
On the National Student Nutrition Day, 1989, the China Student Nutrition Promotion Association, under the auspices of nutritionist Yu Ruomu, combined with the strategic goal of the World Health Organization that everyone should enjoy health care by the year 2000, formulated a ten-year student nutrition work plan from 19 1 to the year 2000. This plan was named "Nursery System Project", and May 20th of each year was designated as China Student Nutrition Day. Its purpose is to publicize the importance of nutrition in students' period and popularize nutrition knowledge. In may of 20001year, the Ministry of education and the Ministry of health jointly issued a document (who CDC no. 200 1 120) legalized "China Student Nutrition Day".