Dyslipidemia

Shujie Wang et al. (2022) · Gut microbes

This randomized trial with 365 adults who had newly diagnosed type 2 diabetes explored whether combining berberine, a plant compound extracted from the Chinese herb Coptis chinensis (Huanglian), with a probiotic mix lowers postprandial lipidemia, the rise in blood fats and cholesterol after a meal. The authors note that cholesterol measured after eating is also an important heart-disease risk marker, that after-meal blood fats are common in diabetes, and that very few treatments target them. Berberine was already known to lower fasting cholesterol, but whether it helps after meals was unknown. Probiotics are live bacteria, and the nine-strain mix here included Bifidobacterium breve. This analysis came from a 12-week, double-blind, placebo-controlled trial at 20 centers in China, with 365 participants split into four groups: placebo (91), probiotics alone (92), berberine alone (84), and both (98). Participants were drug-naive adults aged 20 to 70, averaging about 52. They took berberine pills twice daily before meals, and probiotic powder once daily at bedtime. After a standard 100 g carbohydrate meal, blood drawn 120 minutes later measured cholesterol and triglycerides, and stool samples tracked gut bacteria. Only the combination significantly cut after-meal total cholesterol (24.29 mg/dL drop versus 8.66 with placebo, adjusted P = .001, a gap that chance is very unlikely to explain) and after-meal LDL cholesterol (16.54 versus 7.35 mg/dL, P = .043). Berberine alone and probiotics alone did not differ significantly from placebo for these two measures. After-meal triglycerides fell with berberine alone (P = .037) and the combination (P = .035) equally, so probiotics added nothing there, and HDL (good) cholesterol did not differ between groups. Thirty-one blood lipid molecules changed only with the combination, versus eight with berberine and two with probiotics. In stool, B. breve rose with the combination, and higher levels went with lower after-meal cholesterol. In lab dishes, berberine slowed B. breve growth but switched on its fatty-acid-uptake genes (called fadD). Adverse events were not reported in this paper. The authors conclude that berberine plus probiotics acts synergistically on after-meal blood fats, with the probiotic replacing Bifidobacteria that berberine suppresses and berberine activating the bacteria's fat-handling genes. They state the limits plainly: only 13 weeks and no heart-attack or stroke outcomes, testing only after a carbohydrate meal, and unknown applicability to people already on statins. The authors propose that probiotics containing Bifidobacterium may be needed when berberine is used as a lipid-lowering agent. They suggest studying fatty meals and other gut-related pathways in future work.

Teresa Vezza et al. (2024) · Nutrients

This randomized trial with 66 healthy volunteers explored whether a daily capsule combining garlic powder and a concentrated onion extract lowers LDL cholesterol, the "bad" cholesterol that builds up in artery walls and drives heart and blood vessel disease. Medicines such as statins are usually kept for people with clearly raised LDL cholesterol or several risk factors, so people with slight elevations are generally pointed toward diet and lifestyle changes. Garlic and onion contain organosulfur compounds (sulfur-rich plant chemicals), which the authors say are linked to cholesterol-lowering, antioxidant and anti-inflammatory effects. To the authors' knowledge, human research had mostly looked at garlic alone, and none had combined the two plants in one capsule. Volunteers living in Granada, Spain, with LDL cholesterol between 100 and 190 mg/dL were split at random into two groups of 33. One group took a capsule called Aliocare daily with lunch, holding 86 mg of onion extract and 14 mg of garlic powder, and the other took an identical-looking placebo of plain cellulose. Neither participants nor researchers knew who received which. Blood samples and blood pressure were checked at the start and after 2, 4 and 8 weeks, including markers of oxidation and inflammation, liver and kidney function. After 8 weeks, LDL cholesterol was 6% lower in the capsule group (4% lower at 4 weeks), and total cholesterol about 6% lower. Among those starting above 110 mg/dL, LDL cholesterol dropped 12% by week 8. Triglycerides (blood fats) also fell, while good HDL cholesterol stayed unchanged and glucose did not differ. Oxidized LDL, a form of LDL damaged by oxidation and linked to artery disease, fell about 32% by week 8. Blood pressure was about 5% lower, and no adverse events were reported, with liver and kidney tests staying in the normal range. Compliance exceeded 95%, and participants did not guess their group assignment. Interleukin-6, an inflammation marker, tended to fall with the capsule without reaching significance, and malondialdehyde, another oxidation marker, did not differ. The authors conclude the capsule was safe and improved several heart-related measures, and they suggest garlic and onion may act together, though the study did not test each plant separately. They state plainly that the volunteers were mostly young with LDL cholesterol at the low end of the range, the pandemic limited recruitment, the sample was small and the 8-week duration short. The authors add that recruiting under different conditions would likely have produced higher baseline values and more robust results. They plan larger, longer studies in people with higher LDL cholesterol.

Hadis Hooshmandi et al. (2024) · Journal of ovarian research

This 8-week randomized, double-blind, placebo-controlled trial with 66 women explored whether licorice (Glycyrrhiza glabra) root extract could ease some of the metabolic burden of polycystic ovary syndrome (PCOS), a hormonal condition marked by irregular ovulation, elevated androgen levels, and polycystic ovaries on ultrasound. PCOS frequently occurs alongside obesity and insulin resistance, the body's reduced response to insulin, which raises blood sugar and makes weight loss harder to achieve. The trial paired licorice extract with a calorie-restricted diet to test whether the herb added benefit beyond diet alone. Seventy-two overweight or obese women with PCOS, ages 18 to 45, at a clinic in Yazd, Iran, were randomly assigned to 1,500 mg of standardized licorice extract daily, taken as three capsules before meals, or a matching placebo, both alongside the same reduced-calorie diet, for 8 weeks. Sixty-six women completed the study. Body composition was measured with a bioelectrical impedance analyzer, and blood tests tracked fasting glucose, insulin, and cholesterol levels before and after treatment. Women taking licorice lost more weight than those on diet alone (82.60 kg versus 86.09 kg, a statistically significant difference at p<0.001) and showed larger drops in body mass index and body fat percentage. Their fasting blood sugar (74.0 versus 94.0 mg/dl), insulin (6.68 versus 11.06 µIU/ml), and an insulin-resistance score called HOMA-IR (1.23 versus 2.55) all improved significantly more than in the placebo group (p<0.001), as did triglycerides and total and LDL cholesterol (all lower with licorice) and HDL cholesterol (higher, the more favorable direction) (p between <0.001 and 0.01). A separate measure of insulin-producing capacity, HOMA-B, improved within the licorice group and looked better than placebo before statistical adjustment, but that edge disappeared once the analysis accounted for baseline differences and other factors, a reminder that not every raw difference holds up under closer scrutiny. Diet and activity levels were identical between the two groups throughout the study, and the low-calorie diet alone produced no measurable change in any of these markers over the 8 weeks. The authors propose that licorice's compounds act on fat metabolism, insulin signaling, and cholesterol handling through several biological pathways, though those pathways were not directly measured in this trial. The study ran for only 8 weeks, did not test licorice without the accompanying diet, and relied on 24-hour dietary recall, a self-reported method that can be imprecise. Longer trials isolating licorice's own effect and testing its proposed mechanisms, in more diverse populations than this single-center Iranian cohort, are needed to confirm these results.