Benefits
LDL cholesterol reduction
Human trials report LDL cholesterol reductions with standardized bergamot extract ranging from about 8% to 41% across studies, though a review of 12 studies rated their scientific quality as quite limited. The lowering of total and LDL cholesterol is the most often reproduced finding. Brutieridin and melitidin inhibit HMG-CoA reductase in some laboratory assays; how much this contributes in people is not established.
Triglyceride and VLDL reduction
Bergamot extract has reduced triglycerides in several trials, with reported reductions ranging from about 12% to 40%. The effect is not uniform: in a placebo-controlled randomized trial that measured triglycerides, the change was not statistically significant versus placebo.
HDL cholesterol (inconsistent effect)
Some trials report increases in HDL cholesterol with bergamot, but the size is inconsistent: one 6-month study raised HDL by roughly 8%, and a placebo-controlled randomized trial found no significant HDL change versus placebo. An HDL benefit should not be assumed.
Blood glucose and insulin resistance (mixed results)
Some trials report reductions in fasting and post-meal glucose with bergamot, but findings are mixed: a placebo-controlled randomized trial found no significant change in glucose, insulin or insulin resistance versus placebo. AMPK activation is a proposed mechanism from laboratory work, not a demonstrated clinical effect.
Studied alongside statins
In one small 30-day study (77 patients, about 15 per group), adding bergamot extract to low-dose rosuvastatin lowered LDL cholesterol more than the low statin dose alone. This is early research, not dosing advice. Do not change or reduce a prescribed statin except on the direction of the prescribing doctor.
Liver fat and liver enzyme markers
In a 16-week placebo-controlled trial, a bergamot polyphenol formulation combined with artichoke (Cynara cardunculus) improved liver ultrasound findings and blood markers including ALT and AST versus placebo. A bergamot-only arm was also tested, but only the combination was reported as significant versus placebo, so an effect of bergamot alone is not established. This is not a treatment for fatty liver disease.
Distinct from bergamot essential oil
Important consumer education: bergamot essential oil (used in Earl Grey tea flavoring, perfumes) is a photosensitizing aromatic oil from the peel, a different product from the polyphenolic fraction (BPF) used in supplements. Skin photosensitivity is linked to the essential oil and has not been established for oral BPF.
Mechanism of action
HMG-CoA reductase inhibition (statin-like mechanism)
Brutieridin and melitidin, polyphenols abundant in Citrus bergamia (and also found in some other citrus fruits), carry a 3-hydroxy-3-methylglutaryl group that resembles statins. They inhibited HMG-CoA reductase, the rate-limiting enzyme in cholesterol synthesis, in some laboratory assays, although a liver cell study found no direct inhibition by bergamot extract or its constituents. This is a proposed mechanism; bergamot is a food-derived extract, not a statin drug.
AMPK activation
In a liver cell (HepG2) study, bergamot fruit extract lowered cellular cholesterol, and both the extract and its flavonoid neohesperidin increased AMPK phosphorylation, a marker of activation of this energy-sensing enzyme. Whether this contributes to effects in people has not been shown.
PCSK9 inhibition and LDL receptor upregulation
In laboratory studies, bergamot flavonoids inhibit PCSK9 (proprotein convertase subtilisin/kexin type 9) and increase LDL receptor density on liver cells.
Antioxidant activity
BPF flavonoids (neoeriocitrin, naringin, neohesperidin) have antioxidant activity. In a small 30-day study, bergamot polyphenolic fraction lowered oxidative-stress markers such as malondialdehyde and the oxidized-LDL receptor LOX-1 in white blood cells. Whether this translates into vascular benefit is not established.
Gut microbiome effects (emerging)
Early animal research: in rats on a high-fat diet, a bergamot polyphenol extract combined with albedo and pulp fibres shifted gut bacterial composition and lowered gut-derived lipopolysaccharide. Whether this occurs or matters in people is unknown.
Clinical trials
Early 30-day report from one Italian research group that paired a rat study with 237 patients with hyperlipidemia, with or without high blood glucose, given oral bergamot polyphenolic fraction (BPF). The abstract does not describe randomization or a placebo group.
237 patients with hyperlipidemia, with or without hyperglycemia.
In this early 30-day study of 237 patients with hyperlipidemia, some also with high blood glucose, oral BPF reduced total and LDL cholesterol and triglycerides, raised HDL and lowered blood glucose. It is a single report from one research group, and a later review of 12 bergamot lipid studies rated their scientific quality as quite limited.
Prospective, open-label, parallel-group, placebo-controlled 30-day study. Patients were randomly assigned to placebo (n=15), rosuvastatin 10 or 20 mg/day (n=16 each), bergamot polyphenolic fraction (BPF) 1,000 mg/day alone (n=15), or BPF 1,000 mg/day plus rosuvastatin 10 mg/day (n=15).
77 patients with mixed hyperlipidemia (elevated LDL cholesterol and triglycerides).
In a small 30-day study, adding bergamot extract to low-dose rosuvastatin lowered LDL cholesterol more than low-dose rosuvastatin alone, with reductions in oxidative stress markers. The exact percentage figures often quoted for this comparison are not reported in the trial. This is early research, not a basis for changing a prescribed statin dose.
Randomized, double-blind, placebo-controlled 16-week trial with four arms of 20 patients: bergamot polyphenolic fraction (BPF) alone, artichoke (Cynara cardunculus) extract alone, a 50/50 combination of the two (Bergacyn), or placebo. Statistical comparisons with placebo were reported for the combination.
80 adults with type 2 diabetes for at least 12 months and non-alcoholic fatty liver disease (NAFLD) on ultrasound.
After 16 weeks, the bergamot plus artichoke combination lowered ALT and AST, reduced the ultrasound hepatorenal index (a liver fat measure) and improved oxidative-stress and inflammatory markers versus placebo. The bergamot-only arm showed smaller changes, and its comparison with placebo was not reported, so the trial does not establish an effect of bergamot on its own.