[Dietary consumption of branched-chain amino acids among Chinese middle-aged and elderly population aged 50 and over in 2015].

Objective: To investigate the dietary consumption of branched-chain amino acids(BCAAs)intake status of middle-aged and elderly people 50 years and older in China, and to analyze the distribution differences between different ages, genders and regions.

Methods: The research sample was derived from the 2015 Chinese adult chronic disease and nutrition monitoring data. The survey adopts the stratified multi-stage cluster random sampling method, and selects 298 monitoring points from 31 provinces(autonomous regions and municipalities), a total of 44 218 people aged 50 years and over were sampled. Condiment weighing method, 24-hour dietary review method, and weighing method were used to obtain individual dietary data, and the dietary BCAAs intake of middle-aged and elderly people was calculated based on the Chinese Food Composition Table.

Results: In 2015, the dietary BCAAs of middle-aged and elderly people in China accounted for 45.1% of leucine, 29.8% of valine and 25.1% of isoleucine. The top six dietary sources were cereals, red meat, vegetables, fish and seafood, beans and eggs. There were differences in the intake of three branched-chain amino acids(F=1926.67, P<0.01), the intake of leucine was greater than that of valine, and the intake of valine was greater than isoleucine. There were statistically significant differences in dietary BCAAs intake between different age groups, genders, urban and rural areas and regions(P<0.01), among which men were greater than women(t=12.89, P<0.01), and the south was greater than the north(t=-6.36, P<0.01), the eastern part was larger than the central part, and the central part was larger than the western part(F=82.42, P<0.01). The intake of BCAAs decreased with the increase of age groups(F=22.69, P<0.01), and there was no significant difference in age groups over 70 years old. The dietary intake of BCAAs was higher in the eastern coastal areas and Inner Mongolia, Xinjiang and Tibet.

Conclusion: There were gender, age and geographical differences in dietary BCAAs intake among middle-aged and elderly people in China, and the contribution of various foods to dietary BCAAs was also different.