Safe, yes. Beneficial, questionable.
Chromium picolinate is one of 6 forms of chromium that can be taken as a nutritional supplement. While primary chromium deficiency is exceedingly rare -- it only occurs in a very small group of patients who have a specific type of medically required limited diet - multiple studies have shown that it can help to ease atypical depression and reduce reduce carbohydrate and fat cravings in some people, although even there, the studies have varied greatly in their findings. There is no evidence that it can help athletes develop muscle or anyone to lose weight.
Numerous studies have been done centering around the role it possibly plays in diabetes and the jury is still out on that as well. There was some thought that it might help to decrease insulin resistance but subsequent studies in both diabetics and non-diabetics show mixed results and I have to wonder how much any particular benefit depends on the individual's own body chemistry and metabolism.
The UK is the only country that I am aware of that has issued any warnings or restrictions. The UK Fod Standards Agency recommended that it be avoided in favor of other forms of chromium until it was evaluated for mutagenicity (ability to cause cancer)..There has never been any evidence to substantiate a concern that I could find, so my guess is that this was simply a precautionary note.
Two patients taking chromium supplements subsequently experienced kidney failure. No connection was established and I'm not even sure why those cases were even linked in the most remotest of ways. I took chromium supplements and subsequently got pregnant but I am pretty certain the chromium didn't cause my pregnancy - medical science suggests that intimate relations with my husband was the likely culprit there. But this just shows how medical events can be improperly attributed to one "cause" or another.
There are claims that the picolinate form of chromium supplementation aids in reducing insulin resistance, particularly in diabetics, but a meta-analysis of chromium supplementation studies showed no association between chromium and glucose or insulin concentrations for non-diabetics, and inconclusive results for diabetics.[9] This study has been challenged on the grounds that it excluded significant results.[10] Subsequent trials gave mixed results, with one finding no effect in people with impaired glucose tolerance,[11] but another seeing a small improvement in glucose resistance.[12] A further study on obese adults with metabolic syndrome, was published in 2009, this found no significant effect on insulin sensitivity, but increased short-term levels of insulin. The study also observed no effect on weight or serum lipids.[13]
In a review of these trials it was again concluded that chromium supplements had no effect on healthy people, but that there might be an improvement in glucose metabolism in diabetics, although the authors stated that the evidence for this e