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.”
The research showed that participants taking the supplements had higher metabolic markers and lost more weight during the trials than those taking a placebo. Here at DietsInReview, we are generally leery of diet supplements, and have several concerns about the testing methods. First of all, the studies involved only 12 to 36 participants, which means as few as six participants were given the active pills in one study. “Sample sizes can skew results and clinical trials can be manipulated and show results that make their study look more successful than others,” says Dr. Khan.
Another concern is the health profile of the participant, who reportedly do five to seven hours of aerobic and nonaerobic exercise per week. “Thats a lot of exercise and definitely could skew the results in their favor,” says Dr. Kahn. “Usually people looking into diet pills have tried everything else and nothing has worked for them and I’d say most are exercise novices.” In other words, the research was not conducted with a representative population. “Normally clinical trials are done on healthy individuals but these supplements need to be studied in a specific patient population.” However, Dr. Khan does point out that the study authors admit that more research is need for overweight individuals.
More research is needed before these supplements should be considered safe for long-term use. However, the bottom line is that stimulants alone will not result in long-term weight loss.
December 13th, 2011