Short answer: NCCIH's bottom line: there is not enough evidence that any dietary supplement can manage or prevent type 2 diabetes. For a few ingredients the evidence is weak; for most, it isn't there.
Why citing a federal health agency directly is unusual for this category
Stated as the NIH sources state it, including the parts that do not help sell capsules — a notably candid approach compared to typical supplement marketing.
What the honest summary actually concludes
Several ingredients here have real, if weak and inconsistent, evidence behind them individually — berberine and chromium most of all. What is missing is any published dosing for this specific product.
💡 Worth knowing: none of that makes GlykoNex a scam. It makes it an under-documented botanical blend sold with overreaching claims — which is a different thing.