I like this guy's counsel..Dr. Weil.. this information would help sort out what to look for.
www.drweil.com/vitamins-supplements-herbs/herbs/curcumin-or-turmeric/http://www.drweil.com/vitamins-supplements-herbs/herbs/curcumin-or-turmeric/
"I frequently recommend turmeric supplements, and I believe whole turmeric is more effective than isolated curcumin for inflammatory disorders, including arthritis, tendonitis, and autoimmune conditions. Take 400 to 600 milligrams of turmeric extracts (available in tablets or capsules) three times per day or as directed on the product label. Look for products standardized for 95 percent curcuminoids. Neither curcumin nor turmeric taken orally is well absorbed unless taken with black pepper or piperine, a constituent of black pepper responsible for its pungency. When shopping for supplements, make sure that the one you choose contains black pepper extract or piperine. (If you’re cooking with turmeric, be sure to add some black pepper to the food.). Be patient when taking turmeric supplements: the full benefits may not be apparent for eight weeks."
Oh goodness! I should be adding a bit of black pepper to my green smoothies with tumeric!