Control of lipid levels is one of the most effective strategies for cardiovascular disease prevention. Several studies have demonstrated multiple health‐related properties of Citrus flavonoids on cardiovascular health protection including cholesterol-lowering properties.  Citrus Bergamot is known for its high flavonoid content. Bergamot is an endemic plant of the Calabrian region in southern Italy with a unique profile of flavonoids and flavonoid glycosides present in its juice and mesocarp, such as neoeriocitrin, neohesperidin, naringin, rutin, neodesmin, rhoifolin, and poncirin.

 

    One study tested bergamot polyphenol extract complex on obese individuals with an atherogenic index of plasma (AIP) over 0.34 and mild hyperglycemia. In a 90-day double-blind trial with two Bergamot polyphenol extract doses (650 and 1300 mg daily) and a placebo, significant improvements were observed. Bergamot polyphenol extract led to a substantial reduction in fasting glucose (-12.1% and -18%), triglycerides (-27.1% and -31.9%), and total cholesterol (-23.7% and -28.4%) at the low and high doses, respectively. AIP dropped to 0.27 and 0.19 in the low and high-dose groups. Insulin resistance (HOMA-IR) and insulin levels decreased, and Bergamot polyphenol extract also contributed to a 10% and 14.8% reduction in body weight and a 10% and 15.9% decrease in body mass index in the low and high-dose groups. The study suggested that Bergamot polyphenol extract, with a full spectrum of bergamot juice components, could effectively promote weight loss, and insulin sensitivity, and lower lipid levels to reduce atherosclerosis risk (1).

 

    In an animal study, rats were fed in groups: control group, hypercholesterolemic diet group, hypercholesterolemic diet + 10 mg/day bergamot extracts, and hypercholesterolemic diet + 20 mg/day bergamot extract for 30 days. In animals fed a hypercholesterolemic diet for 30 consecutive days, an elevation of total cholesterol, LDL-cholesterol, and triglycerides was observed compared to baseline values. Administration of bergamot extract (10 and 20 mg/kg/daily) for 30 days in diet-induced hypercholesterolemic rats produced a significant reduction in total cholesterol, LDL-cholesterol, and triglycerides, an effect accompanied by moderate elevation of HDL-cholesterol (2).

 

    The same bergamot extract was given to 237 patients suffering from hypercholesterolemia in doses of 500, 1000, and 1500 mg/day with the higher dose in more complex lipid conditions for 30 days. There were significant reductions in total cholesterol (21 – 31%), LDL-cholesterol (23-36%), triglycerides (28-41%), and an increase in HDL-cholesterol (17-40%). In addition, in the subgroup of patients who also had hyperglycemia, bergamot treatment also significantly reduced glucose levels (19-22%) (2).

 

    To understand the cholesterol-lowering effect of Bergamot extract, a group of scientists conducted both animal and human studies. In the laboratory, using HepG2 cells, they found that Bergamot extract did not harm cell viability within a tested range of concentrations (1-2000 μg/mL) over 4 and 24 hours. The bergamot extract activated AMP-activated protein kinase (AMPK) and significantly reduced cholesterol and triglycerides in HepG2 cells. It also influenced the expression of genes related to lipid synthesis (3).

 

    They also validated these findings in a 12-week clinical trial with 50 moderately hyper-cholesterolemic subjects. Half of them took bergamot extract (400 mg), while the other half took a placebo. Bergamot extract showed positive effects, significantly reducing total cholesterol (from 241.1 ± 13.5 to 219.1 ± 13.8 mg/dL), triglycerides (from 198.5 ± 17.9 to 171.5 ± 11.9 mg/dL), LDL-cholesterol (from 157.3± 8.9 to 137.7± 9.4 mg/dL), fasting plasma glucose (from 88.3 ± 3.2 to 85.3 ± 2.1 mg/dL), and liver enzymes gamma-glutamyl-transferase (gGT); glutamic-oxaloacetic transaminase (GOT); glutamate pyruvate transaminase (GPT) compared to the placebo (3).

 

    The effect of bergamot extract on visceral adipose tissue and metabolic profile was examined in 64 overweight and obese subjects with mild hypercholesterolemia. The study participants were randomized into two groups for 12 weeks: a supplemented group (33 individuals, BMI 27 ± 3 kg/m2 receiving 500 mg of bergamot extract, two daily tablets) and a placebo group (31 subjects, BMI 28 ± 3 kg/m2, two daily tablets) (4).

 

    The parameters of visceral adipose tissue, total cholesterol, and LDL‐cholesterol were significantly decreased in the bergamot group, but not in the placebo group. Compared to those of the placebo group, bergamot supplementation significantly reduced visceral adipose tissue (-14.5%, p= .005), total cholesterol (-7.3%, p<.0002), and LDL-cholesterol (-6.3%, p = .004) (4).

 

    These studies showed that bergamot could provide beneficial effects, such as a decrease of visceral adipose tissue and lower cholesterol levels, which resulted in a very promising protection of cardiovascular health. If you would like to reduce cholesterol levels, consider eating more citrus fruits, such as bergamot.

 

References:

1. Capomolla AS, Janda E, Paone S, Parafati M, Sawicki T, Mollace R, Ragusa S, Mollace V. Atherogenic Index Reduction and Weight Loss in Metabolic Syndrome Patients Treated with A Novel Pectin-Enriched Formulation of Bergamot Polyphenols. Nutrients. 2019 Jun 4;11(6):1271. doi: 10.3390/nu11061271. PMID: 31167512; PMCID: PMC6627641.

2. Mollace V, Sacco I, Janda E, Malara C, Ventrice D, Colica C, Visalli V, Muscoli S, Ragusa S, Muscoli C, Rotiroti D, Romeo F. Hypolipemic and hypoglycaemic activity of bergamot polyphenols: from animal models to human studies. Fitoterapia. 2011 Apr;82(3):309-16. doi: 10.1016/j.fitote.2010.10.014. Epub 2010 Nov 4. PMID: 21056640.

3. Pierdomenico M, Cicero AFG, Veronesi M, Fogacci F, Riccioni C, Benassi B. Effect of Citrus bergamia extract on lipid profile: A combined in vitro and human study. Phytother Res. 2023 Sep;37(9):4185-4195. doi: 10.1002/ptr.7897. Epub 2023 Jun 13. PMID: 37312672.

4. Rondanelli M, Peroni G, Riva A, Petrangolini G, Allegrini P, Fazia T, Bernardinelli L, Naso M, Faliva MA, Tartara A, Gasparri C, Infantino V, Perna S. Bergamot phytosome improved visceral fat and plasma lipid profiles in overweight and obese class I subject with mild hypercholesterolemia: A randomized placebo controlled trial. Phytother Res. 2021 Apr;35(4):2045-2056. doi: 10.1002/ptr.6950. Epub 2020 Nov 13. PMID: 33188552; PMCID: PMC8246838.   Photo by by Jame_PC from Pixabay