Berberine is a natural plant chemical….

in 2007 and 2008, a slew of research studies was published on berberine, with one clinical trial finding it was as effective as the standard drug metformin at reducing blood sugar levels, while reversing insulin resistance and cutting levels of LDL cholesterol (the bad kind)….

In one study, carried out in Milan, a combination of the herb Milk Thistle and Berberine, given to patients with Type 2 Diabetes for 90 days, brought about significant reductions in their HgA1C, fasting insulin, triglyceride, total cholesterol and LDL cholesterol readings. http://www.realdiabetestruth.com/berberine-dibetes-blood-sugar-control/

Berberine is also sometimes recommended for diabetes prevention and therapy, as it does not appear to cause increased body fat as a side effect (associated with Glibenclamide) and may actually reduce body fat. It may also be preferred due to being seen as a “natural” therapeutic option for persons who choose not to use pharmaceuticals… http://examine.com/supplements/Berberine/

Berberine can also reverse insulin resistance on muscle cells and promote both glucose and lipid uptake into the muscle cells. Unfortunately, the mechanism of action that mediates this (AMPK activation) also appears to suppress muscle growth and may actually reduce muscle mass according to one rodent study. Genetically ablating one protein (atrogin-1) reverses this suppression of muscle growth, and thus berberine has potential to be a potent body recomposition agent, pending future research. The interactions with exercise are unknown, but it is theoretically possible that resistance training or contracting muscle tissues can attenuate or reverse these losses.
http://examine.com/supplements/Berberine/

Berberine may also have anti-depressant effects (although at a dose much lower than the other claims, and possibly with no effect at the standard dose of 1500mg daily), fat loss effects, and questionable interactions with skeletal muscle. These claims are not as proven as the aforementioned health benefits. http://examine.com/supplements/Berberine/

Due to AMPK inhibition, berberine is normoglycemic (reduces blood sugar only if elevated). However, the reduction in blood sugar from berberine may make other hypoglyemics more likely to cause reduced blood sugar http://examine.com/supplements/Berberine/

High doses of berberine taken acutely, due to their poor intestinal uptake rate, may cause cramping and diarrhea; for this reason, berberine should be taken in multiple doses throughout the day. http://examine.com/supplements/Berberine/

Berberine’s ability to cross the blood brain barrier suggests it might be helpful in helping with neurological conditions including depression, Alzheimer’s and feelings of pain. It may also offer benefits to the immune system, cardiovascular system and cancer.
http://www.mrsupplement.com.au/berberine

Berberine is best taken at doses between 900mg to 2200mg per day taken in 3-4 divided doses. High single doses of Berberine can cause some intestinal update, which is why the dose is split.  http://www.mrsupplement.com.au/berberine

Berberine would be best paired with protein to help stimulate muscle protein synthesis. It can also be paired with products containing milk thistle, coconut oil and schizandra chinensis to help improve absorption. http://www.mrsupplement.com.au/berberine

The use of a fixed (210 mg) amount of silymarin added to 1000 mg Berberine, the latter is more effective than Berberine alone. http://www.vellejaresearch.com/upload/documenti/193_20131124232610.pdf