Lactose intolerance: worldwide distribution——nmi
Country, regional, and global estimates for lactose malabsorption in adults: a systematic review and meta-analysis——The Lancet
Effects of cow’s milk beta-casein variants on symptoms of milk intolerance in Chinese adults: a multicentre, randomised controlled study——Beijing Research Institute for Nutritional Resources，Clinical Nutrition Center, Huadong Hospital Affiliated to Fudan University, Shanghai
 Clinical evaluation of glutathione concentrations after consumption of milk containing different subtypes of β-casein: results from a randomized, cross-over clinical trial——Nutrition journal
Effects of milk containing only A2 beta casein versus milk containing both A1 and A2 beta casein proteins on gastrointestinal physiology, symptoms of discomfort, and cognitive behavior of people with self-reported intolerance to traditional cows’milk——Clinical Nutrition Center, Huadong Hospital affiliated to Fudan University, Shanghai
 
视频素材：
《a2官方宣传片》 
 
BGM:
Francesco De Luca - Cyclic Dream
Jack Richard Pierce - Waiting Game
Nestor Tomassini - Lagrimas y Sonrisas
DJ Booming - Dusty Clay
The Wizard - Bob BradleyPhilip Guyler
Highdown - Richard Schrieber
Zooming Skywards (Instrumental Version) - Carlie FairburnRoie Shpigler