CBD’s legality depends on a number of factors. It is legal, but that status can vary state to state and federally. One of the determining factors for legality (or not) is whether the CBD is derived from hemp or marijuana. Hemp is a legal plant; marijuana is not. Marijuana has a high THC-content (remember: THC is psychoactive and has mind-altering properties) and is federally illegal in most places.
Absolutely, CBD is the opposite of your typical THC marijuana that makes you want to eat more. CBD has shown the ability to help regulate a person’s blood sugar levels. With regulated blood sugar levels there is less fat-storing hormones produced by the pancreas in a person’s body resulting in less fat being stored. Since more fat can be burned off as energy there will be less fat cells in a person’s body. 

Because CBD oil is non-psychotropic and derived from low or zero THC hemp/cannabis strains it is generally defined as a dietary supplement and therefore is legal in most States and countries so should not pose any problem at a professional or competition level. Please consult your professional organization before assuming that this is the case in your jurisdiction. The United Nations – World Health Organisation (WHO) recently (14 Dec 2017) stated that Cannabidiol (CBD Oil) should no longer be scheduled as a controlled substance. In 2017 the World Anti-doping Agency (WADA) and United States Anti-doping Agency (USADA) approved CBD for use by athletes in over 600 sports.
I have read about studies from Europe (not very specific I know) that suggest CBD might work better for some people if combined with some level of THC. Also, the getting high part can be helpful, although not for everybody, of course. A second point – I don’t hear very much about CBD eliminating or almost eliminating pain for people with severe pain. Helpful, but, so far at least, it doesn’t seem that CBDs can replace opioids or substantially reduce pain for all chronic pain patients. Maybe someday. 
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