Studies of hibiscus, garlic and several other botanicals have reported modest blood pressure changes, though researchers say findings vary widely and herbs should not replace prescribed hypertension treatment.
By yourNEWS Media Newsroom
Research into plant-based approaches to blood pressure management continues to examine hibiscus, garlic, lavender, hawthorn, olive leaf, celery seed and other botanicals, with studies reporting possible cardiovascular effects but also significant limitations in the available evidence.
A 2026 NaturalNews.com article cited research suggesting that compounds found in common herbs and spices may influence cardiovascular health through several biological pathways. The mechanisms discussed included vasodilation, anti-inflammatory activity and antioxidant effects. Researchers, however, noted that many studies involved relatively small groups of participants and used different preparations, doses and formulations, making direct comparisons and firm conclusions difficult.
Those limitations are central to the broader debate over herbs and hypertension. A report published by Health.com said several plants have been investigated for their potential to lower blood pressure but described the overall body of evidence as mixed. Researchers cited in the report said any effects are generally modest, while clinicians cautioned that herbal products can interact with prescription medications.
The National Center for Complementary and Integrative Health states that herbs are not approved by the Food and Drug Administration as treatments for high blood pressure. Instead, they are regulated as dietary supplements. Health professionals cited in the material advised people with hypertension to discuss supplements with their doctors and not discontinue prescribed medication without medical supervision.
Among the plants studied, hibiscus has received particular attention.
A review published in the Journal of Hypertension in 2019 examined randomized controlled trials involving hibiscus tea and reported reductions in both systolic and diastolic blood pressure. Researchers from La Trobe University in Australia identified Hibiscus sabdariffa as the most frequently studied herb in the hypertension research they reviewed.
Hibiscus contains naturally occurring compounds that researchers have investigated for possible effects on blood vessel function and other cardiovascular processes. The broader literature cited in the report proposes that certain herbal compounds may promote vasodilation, affect oxidative processes and influence inflammation, although researchers said variations in study design prevent definitive conclusions about effectiveness.
Garlic has also been studied extensively.
Meta-analyses cited in the material found that garlic consumption, including garlic supplements, may produce modest improvements in blood pressure and other cardiovascular risk factors. One analysis covering more than 100 studies associated garlic intake with small improvements in measures including LDL cholesterol and blood pressure.
Integrative Cardiology also cited a meta-analysis concluding that preparations of garlic, or Allium sativum, modestly reduced blood pressure in people with hypertension. Proposed explanations included widening of blood vessels, antioxidant activity and a mild diuretic effect.
Researchers cautioned that garlic studies have not used a single standardized preparation. Different investigations have tested varying doses, supplement formulations and treatment periods, making it difficult to determine how consistently the findings apply across products.
Other plant-based substances have produced findings of interest as well.
A 2025 study published in the Journal of Human Nutrition and Dietetics analyzed 29 trials involving edible algae. Researchers reported that algae intake was associated with an average decline of about two points in systolic blood pressure and nearly two points in diastolic blood pressure.
Lavender, hawthorn, olive leaf and celery seed were also among the botanicals identified in the material as having supporting research. Integrative Cardiology reported that hawthorn has been studied for improving symptoms associated with congestive heart failure, while hibiscus and garlic have been investigated for their potential blood pressure effects.
The supplied research also cited a randomized, double-blind, placebo-controlled trial involving 74 people with type 2 diabetes. Participants who received 100 milligrams of coenzyme Q10 twice each day experienced a significant reduction in blood pressure over 12 weeks, according to the study.
Although coenzyme Q10 is not an herb, its inclusion reflects the wider body of research examining supplements and naturally derived compounds in relation to cardiovascular health.
Mineral status has also been raised as a potential factor in blood pressure regulation.
A Mercola.com report from 2016 cited estimates that between 50% and 80% of Americans may be deficient in magnesium. Magnesium plays a role in numerous biological processes, including those involved in maintaining normal blood pressure.
The research summarized in the material nevertheless repeatedly points to the difference between finding a biological effect and establishing a supplement as an approved medical treatment.
The FDA does not approve herbal products for treating hypertension, and supplements are regulated differently from prescription medications. Because some herbs can affect blood pressure independently, combining them with antihypertensive drugs can potentially change the effect of those medications.
The report specifically noted possible interactions involving medicines such as diuretics and ACE inhibitors. Clinicians therefore advised patients to disclose all herbs, vitamins and supplements they use when discussing treatment with a physician.
Medical Toxicology of Natural Substances was also cited as saying that relatively little clinical evidence is available to guide treatment in some situations involving hypertension and natural substances. The text identifies medications including sodium nitroprusside and phentolamine as potentially useful agents in relevant clinical settings.
Prescription for Natural Cures similarly states that essential hypertension may sometimes be managed with measures used at home while stressing that anyone with high blood pressure should remain under a doctor’s care.
Natural health advocates have argued that some traditional remedies have not received sufficient scientific examination. At the same time, the research summarized in the report shows why investigators continue to call for larger and more standardized clinical trials before drawing firm conclusions about individual herbs.
Differences in plant species, growing conditions, extraction methods, supplement concentration and dosage can all affect what participants receive in a clinical trial. Those variations can make two products carrying the same herb name chemically different enough to produce different results.
Blood pressure itself is measured using two readings. Systolic pressure, represented by the upper number, measures pressure in the arteries when the heart contracts. Diastolic pressure, represented by the lower number, reflects pressure between heartbeats.
The supplied material also cites a Mercola.com report described as dating to 2019 that lists 690,882 U.S. heart disease deaths in 2020 compared with 633,842 in 2015, an increase of 9% over six years. High blood pressure was identified as an important cardiovascular risk factor.
Across the studies cited, hibiscus and garlic have some of the most frequently reported associations with lower blood pressure, while other herbs and supplements remain subjects of continuing investigation. Researchers have not concluded, however, that herbal products should replace established hypertension treatment.
The central finding across the material is that some botanicals may influence blood pressure, but the size and consistency of those effects remain uncertain. Researchers continue to call for better-standardized studies using clearly defined preparations and dosages, while clinicians advise people taking blood pressure medication to consult a health professional before adding herbal supplements to their regimen.
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