Meldonium

While i was surfing somehow i reached to to wada's banned substance in sports. I wondered what they do why they banned. Seen most of them banned having short term positive effects and long term term negative effects thus staying in definition of doping (to me dopes are banned for not letting people harm themselves in order to get competitive edge) But when i searched for this substance i have seen lots of positve effects (some are long term) but couldnt find any info about about its serious negative effects anywhere (except pregnancy). It is banned inside and outside competitions. Something should not be banned if doesnt have negative effects. If the reason it gives positive edge, then training, sleeping, eating all of them should be prohibited. Since i may be sleeping better than you, or i can afford better foods than you, or simply i can have more time to train then you ?

What i am missing ?