According to WebMD, the oral supplements of BCAAs haven’t registered harmful effects. Still, side effects may include:
Nausea
Pain
Headache
BCAAs have also been recorded to spike insulin resistance in the body. It may affect blood sugar levels. Hence, if anyone is having surgery then he/she must avoid amino acids in any form.
On the other hand, there’s a long history of professional sportspersons and bodybuilders taking BCAAs regularly. They have been taking BCAAs to pump, cut, or bulk their bodies. Yet there are no visible side effects registered so far.