Benefits
Healthy cholesterol levels
In a 6 month study of 80 adults with higher than ideal cholesterol, everyone took the extract and there was no placebo group. Average total cholesterol fell from about 255 to 224 mg/dl, LDL from about 178 to 143 mg/dl and triglycerides from about 159 to 133 mg/dl, while HDL rose from about 50 to 54 mg/dl. Those are before and after figures within one group rather than a comparison against placebo.
Small dense LDL
In that same single group study, the LDL profile shifted away from the small, dense bands linked with cardiovascular risk. The largest of those bands, LDL-3, went from about 14.5 to 9.0 percent of total LDL, while the large LDL-1 band rose from about 41.2 to 49.6 percent. These are proportions of the LDL profile before and after, in a group with no placebo comparison.
Cardiovascular support
The same study measured carotid artery wall thickness by ultrasound and reported a drop from 1.2 to 0.9 mm over 6 months. That number deserves caution. Controlled trials of prescription cholesterol medicines typically shift carotid wall thickness by hundredths of a millimeter or less over a year, so a change of this size in half a year is far more than a study without a control group can support.
Mechanism of action
HMG-CoA reductase modulation
Brutieridin and melitidin carry a fragment resembling the active part of a statin, and laboratory work suggests they can inhibit HMG-CoA reductase, the enzyme that controls cholesterol synthesis. This is a proposed explanation from chemistry and cell studies rather than something measured in people, and these two flavonoids are not part of what the extract is standardized to.
Antioxidant flavonoids
The flavonoid mix is thought to limit oxidative modification of LDL and to support the lining of blood vessels. Neither was measured in the 6 month study cited on this page, so treat this as a proposed mechanism rather than a demonstrated one.
Clinical trials
Six month prospective study of Bergavit at a fixed 150 mg of flavonoids daily, measuring plasma lipids, LDL subfractions and carotid artery wall thickness. Every participant received the extract. There was no placebo group and no randomization, and the authors list the missing control group as a limitation of their own work. (Toth et al., Frontiers in Pharmacology)
80 adults, mean age 55, with moderate hypercholesterolemia (LDL 160 to 190 mg/dl). 6 months, single group, no placebo.
Over 6 months, average total cholesterol fell from 6.6 to 5.8 mmol/l (about 255 to 224 mg/dl), LDL from 4.6 to 3.7 mmol/l (about 178 to 143 mg/dl) and triglycerides from 1.8 to 1.5 mmol/l (about 159 to 133 mg/dl), while HDL rose from 1.3 to 1.4 mmol/l (about 50 to 54 mg/dl). The share of LDL in the small, dense bands fell and large LDL rose. Carotid wall thickness was reported to fall from 1.2 to 0.9 mm. Every one of these is a before and after value inside a single group that all received the extract, so ordinary variation over time, seasonal change and any diet or lifestyle change the participants made are not separated out. The carotid figure in particular is far larger than what controlled trials of prescription cholesterol medicines produce in a year.