Garlic and onion extract for cholesterol in healthy volunteers
What it found
In 64 healthy adults with slightly raised cholesterol, a daily capsule of onion extract and garlic powder lowered LDL and total cholesterol over 8 weeks.
The authors say it was well tolerated.
What they found
Studies in people
LDL cholesterol
In people taking the supplement, LDL cholesterol fell by about 4% at 4 weeks and 6% at 8 weeks compared with the start. Those who started with LDL above 110 mg/dL saw a 5% drop at 4 weeks and a 12% drop at 8 weeks.
Total cholesterol
Total cholesterol in the supplement group dropped by about 6% at both 4 and 8 weeks compared with the start. The placebo group stayed largely stable.
Blood pressure
Both systolic and diastolic blood pressure improved in all participants, with the largest changes in those taking the supplement, a reduction of about 5% at 8 weeks.
Oxidised LDL
In people taking the supplement, oxidised LDL fell by about 10% at 2 weeks, 16% at 4 weeks and 32% at 8 weeks compared with the start.
Liver and kidney markers
Liver enzymes ALT, AST and gamma GT and kidney marker creatinine stayed within normal ranges in the treated group throughout the trial. Some of these markers even went down.
Other blood fats and glucose
Triglycerides fell significantly in the supplement group, while glucose showed no significant difference. HDL cholesterol did not change in the supplement group but rose slightly in the placebo group.
What the authors conclude
“In conclusion, daily consumption of a single capsule containing garlic powder and a concentrated onion extract rich in organosulfur compounds was safe and beneficial for improving cardiovascular health parameters in healthy volunteers with moderate levels of LDL cholesterol.”
Also in their conclusions
- They conclude that daily consumption of a single capsule containing garlic powder and a concentrated onion extract rich in organosulfur compounds was safe and beneficial for improving cardiovascular health parameters in healthy volunteers with moderate levels of LDL cholesterol.
- They suggest that this treatment could serve as a promising therapy for managing hypercholesterolemia in healthy subjects with a slight increase in plasma LDL cholesterol levels.
- They advise that integrating this supplement into a balanced diet may enhance overall cardiovascular health benefits.
How it was done
People with mildly raised cholesterol are often advised against cholesterol-lowering drugs because of side effects, and are steered towards diet and lifestyle changes instead. The authors wanted to test whether a garlic and onion supplement could help in this situation.
They recruited 66 healthy volunteers aged 18 to 65 with LDL cholesterol between 100 and 190 mg/dL, and gave them either one capsule a day of onion extract plus garlic powder or a placebo for 8 weeks. Blood tests and measurements were taken at the start, at 2 weeks, 4 weeks and 8 weeks.
What it can’t tell you
- The study lasted only 8 weeks, so it cannot show whether the cholesterol changes last longer or lead to fewer heart problems.
- The participants were mostly young and healthy, so the results may not apply to older people or those with higher cholesterol levels.
Who paid
- Funding
- Funded by Junta de Andalucía; Unidad de Excelencia para el Estudio de los Trastornos del Envejecimiento (UNETE) (from the PubMed record).
- Conflicts
- The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.
- Authors work at
- Virgen de las Nieves University Hospital, Spain; Instituto de Investigación Biosanitaria (ibs.GRANADA), Spain; DMC Research Center, Spain
The paper
- Title
- LDL-Cholesterol-Lowering Effects of a Dietary Supplement Containing Onion and Garlic Extract Used in Healthy Volunteers
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Vezza T, Guillamón E, García-García J, et al (2024). LDL-Cholesterol-Lowering Effects of a Dietary Supplement Containing Onion and Garlic Extract Used in Healthy Volunteers. Nutrients. doi:10.3390/nu16162811Free full textPubMed 39203947DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error