Gereifter Knoblauchextrakt vs Alpha-Liponsäure

Built from two randomised placebo-controlled trials of aged garlic extract taken on top of blood-pressure medication by people whose hypertension was not controlled. Ried 2013 (PMID 23169470), a dose-response trial in 79 general practice patients over 12 weeks, gave 240, 480 or 960 mg a day: 240 mg did not lower systolic pressure compared with placebo, 480 mg lowered it by 11.8 mmHg (P=0.006), and 960 mg reached a borderline 7.4 mmHg at 8 weeks (P=0.07). Ried 2010 (PMID 20594781), in 50 patients over 12 weeks, found 960 mg a day lowered systolic pressure by 10.2 mmHg (p=0.03) in those starting at 140 mmHg or above, with no significant change in those below 140. The 960 mg point sits no higher than 480 mg because the one trial that compared doses found no extra benefit at the higher dose. 480 mg is the lowest dose with a significant fall. No optimal dose is set, because that trial's arms were small and 960 mg lowered pressure in the second trial, and no ceiling is set on this curve. A 2024 meta-analysis that reported a benefit only above the doses these trials tested has been retracted (PMID 39437887), and no point on this curve rests on it. Aged black garlic extracts dosed by their S-allyl cysteine content (PMID 35276764, 37686723) are a different preparation and are not placed on this axis, and neither is a 2,400 mg trial whose blood pressure result was a secondary before-and-after change in the garlic group (PMID 32349742).

The points come from the SYDNEY 2 trial (PMID 17065669), which gave 181 people with diabetic polyneuropathy 600, 1,200 or 1,800 mg once daily or placebo for 5 weeks. All three doses beat placebo on the Total Symptom Score, with about the same size of effect: responder rates (a 50% or greater fall) were 62%, 50% and 56% against 26% on placebo, and effectiveness here is the responder rate above placebo. Nausea, vomiting and vertigo rose with dose, and the authors judged 600 mg once daily the best balance of benefit and risk. Doses below 600 mg were not tested. A 6-month trial of 1,200 mg a day in 200 patients (PMID 32370731) found benefit with mild nausea in 6 patients and no withdrawals, which is the basis for the 1,200 mg ceiling. A meta-analysis of 10 trials reported a dose-related trend in symptom scores (PMID 37630823), which the one head-to-head dose trial did not show.