If you're so sure it's not effective then why is the NIH sponsoring the ACTIV-6 clinical trial?
https://www.nih.gov/research-training/medical-research-initi...
https://www.nih.gov/research-training/medical-research-initi...
https://www.tandfonline.com/doi/full/10.1080/10408398.2020.1...
https://bjsm.bmj.com/content/early/2021/07/21/bjsports-2021-...
Yes