Intermittent fasting where you consume all your calories for the day in an 8 hour window each day, e.g., from noon to 8pm works well for most people. This sets up your hormone profile to burn stubborn fat (12 to 16 hours into your fast is the “golden hour” where you will be able to lose a lot more fat than muscle). You are basically putting yourself into mini-starvation and your body responds by releasing hormones (catecholamines) that enable you to tap into your emergency energy reserves aka “stubborn fat.”
The supplement is also named after the desired compound in this herb that achieves the fat-burning effects: forskolin (also called “coleonol”), a labdane diterpene unique to Indian Coleus only. Labdane diterpenes are found in many other plants, but what makes the ones from Indian Coleus so exciting is their unique, impressive effects: found in no other plant in the world. (1)
I am not saying it doesn’t work for weight loss or belly melting; we don’t have good enough evidence to know whether it does or not. I’m not saying people shouldn’t take it, although they shouldn’t assume it’s perfectly safe. I’m only saying there is inadequate evidence for anyone to make the claims Dr. Oz and other proponents have made for it. If we had such limited evidence for a proposed new prescription drug, I doubt if Dr. Oz would want the FDA to approve it for marketing. The double standard is obvious.
One of the most common complications of diabetes is damage to nerves known as diabetic neuropathy, which takes several forms and can cause serious symptoms throughout the body from muscle weakness to blindness. A study in rats found that supplementing with curcumin significantly reduced diabetic peripheral neuropathic pain (typically localized to feet, legs, arms and hands). (42) 

During the surgery doctors removed liver tissue and they then then measured the levels of curcumin in the tissue. The results showed that the level of curcumin absorbed into the liver was not high enough to have any anticancer effect. The researchers suggested that future clinical trials of curcumin should focus on preventing bowel tumours. Several studies have shown that curcumin taken as capsules does get absorbed by the gut and is present in the blood. But the amount in the blood is small. <