Several preliminary studies show that supplements Jack3d and OxyElite Pro have minimal side effects for short-term use while boosting the body’s metabolism, however we still have some concerns. The four small-scale studies focused on the two supplements were published on the open-access research site Libertas Academica. Both supplements contain “dimethylamylamine” (DMAA), which is a stimulant similar to caffeine and is also used as a nasal decongestant.
Two separate two-week studies analyzed the safety of the supplements by measuring various health indicators, including renal and liver function, blood pressure and heart rate. They showed report that Jack3d and OxyElite Pro have low rates of side-effects for short-term use, although both triggered increased heart rate. In addition to DMMA, both supplements contain caffeine equivalent to two to four cups of coffee, which may account for elevated heart rate. Subjects were asked to take one or two capsules per day. Some participants taking two pills reported feeling jittery, on-edge, shaky and trouble sleeping while taking two capsules, however these symptoms disappeared when the dose was reduced to one capsule per day.
“I think its reasonable to think that the caffeine is what is doing this not the DMAA,” says DietInReview’s pharmaceutical expert Dr. Sarah Khan. “Studies would need to be conducted head to head to compare the results for just DMAA alone versus caffeine. The first study did find an increase in systolic blood pressure so anyone with pre-hypertension or hypertension would definitely want to avoid this supplement.”