Garlic

Sedighe Esmaeilzadeh et al. (2025) · Reproductive biology and endocrinology : RB&E

This systematic review and meta-analysis combined 17 randomized controlled trials (15 pooled, 996 women) to ask whether antioxidant supplements ease the pain of endometriosis, a chronic inflammatory condition in which tissue like the uterine lining grows outside the uterus. Oxidative stress (damage from unstable oxygen molecules called free radicals) is thought to feed the inflammation and pain, so antioxidants such as melatonin, vitamins C, D, and E, curcumin (from turmeric), garlic, silymarin (from milk thistle), and resveratrol have been tested. Results across individual trials have been inconsistent, and earlier reviews were narrower, so this one searched seven sources through January 2025 and graded the certainty of the evidence. Included trials enrolled women aged 18 to 49 with confirmed endometriosis, mostly in Iran, plus Egypt, Brazil, the United States, China, and Sweden. Women took an oral antioxidant or a comparator (placebo, standard care, or nothing) for 8 to 24 weeks. The review pooled three pain outcomes using standardized mean differences (a way to combine different pain scales into one measure): painful periods (dysmenorrhea), painful intercourse (dyspareunia), and chronic pelvic pain. Study quality was graded with Cochrane RoB 2, and evidence certainty with GRADE. For painful periods, 12 trials (706 women) showed lower pain with antioxidants (SMD -1.26; 95% CI -2.19 to -0.32, equal to about 3 points on a 0 to 10 scale), but results varied enormously between trials (I² = 90.1%), so the evidence was rated low certainty. Melatonin stood out (SMD -1.89; 95% CI -2.48 to -1.31), while vitamin D, vitamins C plus E, omega-3, resveratrol, and curcumin did not reach significance. Painful intercourse showed no significant effect (SMD -1.01; 95% CI -2.27 to 0.24). Chronic pelvic pain fell in the pooled analysis (SMD -1.07; 95% CI -1.71 to -0.42), but the evidence was very low certainty and the effect vanished when trials with conflicts of interest were removed. Single trials of garlic powder and silymarin reported lower pain, whereas curcumin did not. Only 7 of 17 trials had low risk of bias. The authors say the findings do not support routine antioxidant use for endometriosis pain, and describe melatonin as the most promising candidate for painful periods, pending confirmation. Limitations include very high heterogeneity, small trials, different antioxidants and doses, bigger effects in weaker studies, and little control of baseline vitamin levels or diet. The paper did not report adverse events. The garlic and silymarin findings come from single trials, and publication-bias testing found no small-study effects for chronic pelvic pain. The authors call for larger, standardized trials.

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.

Janmejaya Samal (2015) · Journal of intercultural ethnopharmacology

This systematic review pooled published research on using Ayurveda, India's traditional medical system, alongside standard drugs for pulmonary tuberculosis (PTB) — a bacterial lung infection that remains one of India's leading causes of death. The review searched PubMed through April 2015 and found six studies worth including: four human trials testing Ayurvedic herbal formulas as add-ons to standard anti-TB drugs (ATDs), and two lab studies testing plant extracts directly against the TB bacterium. In Ayurveda, PTB is traditionally understood as Rajayakshma, a wasting condition tied to depleted bodily tissues (dhatu) and vital reserve (ojas) — explaining why many of the formulas studied are rejuvenative "Rasayana" tonics rather than antibiotics. The four clinical trials enrolled 30 to 133 PTB patients each, all in India, and ran from 28 days to 6-8 months. Participants took Ayurvedic formulas — a nine-herb Rasayana capsule, a liquid tonic called Bhringarajasava, Ashwagandha with Chyawanprash, or a hepatoprotective blend called Liv-600 — alongside their prescribed drug regimen (DOTS). Researchers tracked symptoms like cough and fever, body weight, X-ray changes, drug blood levels, and liver enzymes. The two lab studies tested leaf and plant extracts against TB bacteria in culture, measuring the lowest concentration that stopped bacterial growth. Across the trials, Ayurvedic add-ons consistently eased symptoms and supported weight gain more than standard treatment alone (p<0.001 in the largest trial). One striking finding: Ashwagandha plus Chyawanprash raised blood levels of two key TB drugs, isoniazid and pyrazinamide, by 7-10% (meaning the body absorbed more of the medicine that actually kills the bacteria) — potentially valuable given rising drug resistance. The hepatoprotective blend showed no harmful rise in liver enzymes, suggesting it may guard against the liver damage these drugs can cause. In the lab, extracts from four of five tested legumes completely stopped bacterial growth at a low concentration (50 micrograms per milliliter), and extracts from five other plants inhibited even drug-resistant TB strains by up to 95%. These findings position Ayurvedic formulas as promising supportive care — easing symptoms, protecting the liver, and possibly boosting drug absorption — rather than replacements for standard TB treatment, which no study tested. The evidence base is thin: only six studies total, all small, mostly from India, with just one describing blinding and none pooling results statistically. The authors call for properly designed clinical trials of the lab-active plants, especially against multidrug-resistant TB. The evidence reviewed concerns Ayurvedic preparations as adjuncts to prescribed drug therapy; none of it addresses their use instead of it.

Zhiyong Long et al. (2023) · Frontiers in immunology

Whether the plant compounds often discussed for rheumatoid arthritis — turmeric, green tea, pomegranate, garlic — actually do anything is the question this meta-analysis set out to answer. This review gathered every randomized trial it could find on the question: 47 trials, nearly 3,900 people, fifteen different plant polyphenols, from Iran, China, Korea, Egypt, Japan, Brazil, India and the United States. The clearest picture came from two of them. The first is total glucosides of paeony, an extract of Chinese peony root that is a licensed prescription medicine in China. Twenty-three trials tested it — always added to standard RA drugs like methotrexate, never instead of them. Disease activity scores came down, and so did CRP, ESR and rheumatoid factor, the blood markers doctors track. The most interesting result: people taking it reported *fewer* side effects than people on the standard drugs alone. That fits how it is used clinically — it appears to soften the toll the conventional drugs take on the liver and stomach. The second is curcumin, the yellow compound in turmeric. Five trials, and the same direction: lower disease activity, lower inflammatory markers, no extra side effects. Green tea polyphenols looked promising across two trials. Saffron did not show a clear effect. Everything else — pomegranate, garlic, resveratrol, sesame, cinnamon, ginger, kudzu, cranberry, olive oil, quercetin — rests on one or two small trials apiece, which is encouraging but not yet evidence that bears weight. The honest caveat, which the authors state plainly themselves: the trials disagreed with each other a great deal, most were small, and when the researchers sliced the data by dose and duration some of the headline benefits faded. Nearly all of these were add-on studies. Nobody tested a polyphenol against methotrexate, so the evidence says nothing about replacing a prescribed medication. What it does support is turmeric and peony extract as the best-evidenced candidates, studied as additions to existing treatment rather than replacements for it.