The decreased molar ratio of phytate:zinc improved zinc nutriture in South Koreans for the past 30 years (1969-1998)

For the assessment of representative and longitudinal Zn nutriture in South Koreans, Zn, phytate and Ca intakes were determined using four consecutive years of food consumption data taken from Korean National Nutrition Survey Report (KNNSR) every 10 years during 1969-1998. The nutrient intake data are presented for large city and rural areas. Zn intake of South Koreans in both large city and rural areas was low during 1969-1988 having values between 4.5-5.6 mg/d, after then increased to 7.4 (91% Estimated Average Requirements for Koreans, EAR = 8.1 mg/d) and 6.7 mg/d (74% EAR) in 1998 in large city and rural areas, respectively. In 1968, Zn intake was unexpectedly higher in rural areas due to higher grain consumption, but since then until 1988 Zn intake was decreased and increased back in 1998. Food sources for Zn have shifted from plants to a variety of animal products. Phytate intake of South Koreans during 1969-1978 was high mainly due to the consumption of grains and soy products which are major phytate sources, but decreased in 1998. The molar ratios of phytate:Zn and millimmolar ratio of phytate×Ca:Zn were decreased due to the decreased phytate intake in South Koreans, which implies higher zinc bioavailability. The study results suggest that Zn nutriture has improved by increased dietary Zn intakes and the decreased molar ratio of phytate:Zn in South Koreans in both large city and rural areas.