This 9 minute video is a wonderful explanation of some of the reasons why yoga is so good for us, by Dr Mithu Storoni. Dr Storoni is a medical doctor and neuro-ophthalmologist, as well as being a yoga practitioner and yoga teacher.
In short, in order to increase our chances of living a longer, happier and healthier life through the practice of yoga, we just need to keep doing what we’re doing (and isn’t that satisfying!):
https://uplift.tv/2018/science-behind-yoga-stress/