Herbs for Blood Pressure and Cholesterol: What Research Shows
What reviews and health agencies found for hibiscus, garlic, hawthorn, green tea and sage on blood pressure and cholesterol, plus the licorice and red yeast rice warnings.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Never replace prescribed blood pressure or cholesterol treatment with a herb. The NHS says not to stop any prescribed medicine without first talking to your doctor. [1] Call 911 (in the US) for sudden chest pain or pressure that does not go away, especially with pain spreading to the arm, neck or jaw, sweating or shortness of breath. The NHS describes these as possible signs of a heart attack. [2]
Two herb-related warnings come first. Licorice root contains glycyrrhizin, which NCCIH links to irregular heartbeat and cardiac arrest, including at small amounts in people who eat a lot of salt, have hypertension, or have heart or kidney conditions. [3] Red yeast rice products can contain statin-like compounds and a kidney-damaging contaminant (details below). [4]
Start with the condition
High blood pressure usually causes no symptoms, so the only way to know is to have it checked. [2] High cholesterol also does not usually cause symptoms and is found by a blood test. [5] The NHS says lifestyle changes and blood pressure medicines can help people stay healthy, and that cholesterol can be lowered by eating healthily and exercising, with medicine needed by some people. [2][5] The herbs below are studied as add-ons, not replacements. For wider context see Ayurveda for high blood pressure and cholesterol.Blood pressure
Hibiscus (Hibiscus sabdariffa; family Malvaceae). [6]
- Research: A meta-analysis of 13 randomized trials (1,205 people with mild-to-moderate hypertension) found hibiscus lowered systolic and diastolic pressure compared with placebo. It was not effective in people with metabolic syndrome and not better than blood pressure drugs, and the authors called for long-term trials. [7] A 2025 overview of reviews (26 trials, 1,797 people) also reported lowering, with a small, clinically insignificant rise in a liver enzyme (AST), and said long-term and therapeutic dosing safety needs careful monitoring. [8] Label: promising but limited. These reviews as summarized did not separate tea from extract, so a result for one form should not be assumed for another. See hibiscus and hibiscus tea.
Garlic (Allium sativum, the bulb; family Amaryllidaceae). [6]
- Research: NCCIH says limited evidence suggests garlic supplements may reduce blood pressure to a small extent in people with high blood pressure. [9] A 2025 meta-analysis of 10 trials found reductions but concluded the overall impact on hypertension may be limited. [10] Label: promising but limited. See garlic.
Hawthorn (Crataegus monogyna and related species). [6]
- Research: NCCIH reports conflicting evidence in heart failure. [11] For blood pressure itself: Proper evidence not found in the sources we read (we read NCCIH's hawthorn page). Safety: the FDA warned about products labeled "tejocote root" that actually contained yellow oleander, a toxic plant, and no study has tested hawthorn beyond 16 weeks. [11] See hawthorn.
Licorice (Glycyrrhiza glabra and related species). [6] Label: evidence of harm for blood pressure and heart rhythm in the groups above. NCCIH also reports interactions with corticosteroids. [3]
Cholesterol
| Item | What the source found | Label |
|---|---|---|
| Garlic supplements | May lower total and LDL cholesterol to a small extent in people with high cholesterol [9] | Promising but limited |
| Green tea (extract capsules mostly) | Small reductions in total and LDL cholesterol in trials, mostly of extract supplements [12] | Promising but limited |
| Sage (Salvia officinalis) | A few studies suggest benefit on blood lipids [13] | Insufficient evidence |
| Red yeast rice (fermented rice, not a herb) | Products with a lot of monacolin K, which is structurally identical to lovastatin, may lower cholesterol, but the amount in products varies widely [4] | Mixed, with safety concerns |
For fiber and omega-3 products, which are covered elsewhere, see psyllium and fiber supplements and omega-3 evidence by use.
Red yeast rice in more detail
NCCIH says some commercial products contain little or no detectable monacolin K while others contain large amounts, and consumers cannot tell which from the label. [4] Products with significant monacolin K can have the same side effects as statin drugs, including muscle, kidney and liver damage, and may interact like statins. [4] Some products contain citrinin, a toxic contaminant that can damage the kidneys. [4] It is not recommended in pregnancy or breastfeeding. [4]Frequently asked questions
Can hibiscus tea lower blood pressure?
Reviews of randomized trials report lowering compared with placebo in people with mild-to-moderate hypertension, but hibiscus was not better than blood pressure drugs and long-term trials are still needed. [7]
Does garlic lower cholesterol?
NCCIH says garlic supplements may lower total and LDL cholesterol to a small extent in people with high cholesterol. [9]
Is red yeast rice a natural alternative to a statin?
Not a safe swap. NCCIH says its monacolin K is structurally identical to lovastatin, the amount in products varies, some contain a kidney-damaging contaminant, and side effects can match statins. [4]
Is licorice safe if I have high blood pressure?
NCCIH links glycyrrhizin in licorice to serious heart effects, including in people with hypertension or heart or kidney conditions. [3] Ask a prescriber or pharmacist first.
Can I stop my blood pressure pill if I take a herb?
No. The NHS says not to stop a prescribed medicine without first talking to your doctor. [1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
How to read this page
Safety and medicines
- Green tea: NCCIH says no safety concerns have been reported for green tea as a beverage, but extract supplements can raise blood pressure, and liver injury, though uncommon, has been reported mainly with extracts in tablet or capsule form. [12] At high doses, green tea has been shown to lower blood levels of nadolol (a beta-blocker), and green tea extract can lower blood levels of atorvastatin. [12]
- Garlic: supplements may increase bleeding risk, which matters before surgery and with anticoagulants or aspirin. [9] Some people are allergic to garlic. [9]
- Blood pressure and statin medicines: the NHS lists statins, high blood pressure medicines such as ramipril, and blood thinners such as warfarin among medicines that may not mix well with herbal medicines. [1] Ask a pharmacist first. See herbs and diabetes, blood pressure and heart medicines and how interactions work.
- Pregnancy, children, kidney or liver problems: the NHS advises against herbal medicines in these situations. [1] NCCIH says garlic in larger-than-food amounts may not be safe in pregnancy or breastfeeding. [9]
- Surgery: tell the surgical team about every herb. See supplements before surgery.