Hawthorn Berry: Benefits, Heart Research and Side Effects

Hawthorn berry is the small red fruit of the hawthorn shrub, a member of the rose family in the genus Crataegus, and it is sold as capsules, teas, tinctures and extracts promoted for the heart. The National Center for Complementary and Integrative Health (NCCIH) says there is little or no quality evidence for most uses. Heart failure is the one area with real trials, and the results conflict: an older review found small symptom gains, while the largest trial found no effect on cardiac events. Because people interested in hawthorn often take heart medicines, the most important step is talking to your cardiologist first.

Peptide Labs sells supplements and hemp products, but none of them lists hawthorn, and this article does not recommend any product. It is general information, not medical advice.

What is hawthorn berry?

Hawthorn is a flowering shrub or tree that grows in temperate regions around the world. NCCIH notes it was traditionally used for heart disease, digestion, circulation, and kidney and bladder problems, and on the skin for sores, itching and frostbite. Today it is promoted for the heart and blood vessels, weight loss and anxiety.

Supplements use different parts of the plant. Many products are sold as berry powders or teas, while most European clinical research used standardized extracts of hawthorn leaf with flower. That matters when you read claims: a study on a leaf and flower extract does not automatically apply to a berry powder or tea, because the plant parts and their compounds differ.

Hawthorn berry benefits: what the research shows

When people talk about hawthorn berry benefits, they almost always mean the heart. NCCIH says the evidence on heart failure is conflicting, and that there is not enough evidence to know whether hawthorn affects angina, abnormal heartbeat or plaque in the arteries. There is no evidence that it affects weight loss, and its effect on anxiety is unclear. These are the main heart failure studies, all in people already under a cardiologist’s care.

The Cochrane review

In 2008 Cochrane reviewers pooled double-blind, placebo-controlled trials of hawthorn leaf and flower extract, mostly given on top of usual heart failure care. Across 10 trials with 855 patients, hawthorn did better than placebo on maximal workload, exercise tolerance and symptoms such as shortness of breath and fatigue. The trials were small, and almost none reported deaths or hospital stays, which are the outcomes that matter most.

The SPICE and HERB CHF trials

The SPICE trial was the large test. It randomized 2,681 adults with moderate heart failure and a weak heart pump to a hawthorn extract or placebo for two years. Time to a first cardiac event was about the same in both groups (27.9% versus 28.9% had an event), a difference that was not statistically significant. Side effects were similar. The authors pointed to a possible signal on sudden cardiac death in one subgroup, but subgroup findings like that need confirmation.

The smaller HERB CHF trial at the University of Michigan gave 120 people hawthorn or placebo for six months alongside standard care. It found no difference in walking distance, quality of life or other function measures, and the hawthorn group reported significantly more adverse events, mostly not heart related. NCCIH notes that one study suggested a hawthorn preparation may have raised the early risk of heart failure getting worse, possibly through interactions with the patients’ drugs.

Taken together, hawthorn has not been shown to change the course of heart failure. If you have heart failure, high blood pressure or chest pain, talk to your cardiologist before considering hawthorn, and never use it in place of prescribed care.

Hawthorn side effects and drug interactions

NCCIH says some hawthorn supplements might be safe in the short term, but no studies have tested whether it is safe beyond 16 weeks. Reported hawthorn side effects include:

• Dizziness
• Nausea, vomiting and diarrhea
• Muscle pain

Interactions are the larger concern. Hawthorn is promoted for effects on the heart and blood vessels, and people interested in it often take heart medicines such as digoxin, beta blockers, nitrates or other blood pressure drugs. Effects could add up in ways that are hard to predict. A 2003 crossover study in eight healthy volunteers found that three weeks of hawthorn extract did not change digoxin levels, but a tiny study in healthy people cannot show that the combination is safe for heart patients. Bring every supplement to your cardiologist or pharmacist so they can review it with your medicines.

Little is known about hawthorn in pregnancy or breastfeeding, so avoid it unless your obstetric provider says otherwise. People taking diuretics or watching potassium and blood pressure may also find our guides to water pills, potassium and licorice root useful, since each covers herb and medicine combinations that affect the heart.

The tejocote root warning

In January 2024 FDA published a list of products labeled “tejocote root,” sold as Mexican hawthorn (Crataegus mexicana), that actually contained yellow oleander. NCCIH describes yellow oleander as a toxic plant that can harm the nervous system, heart, stomach and intestines, and FDA warned the products could cause severe harm or be fatal. Some people had been using them for weight loss. This is a substitution problem rather than a hawthorn effect, but it shows why testing and a trustworthy supply chain matter. Our article on whether fat burners work covers more weight-loss product risks.

How to read a hawthorn label

1. Check the plant part: berry, leaf and flower, or root. Most clinical research used leaf and flower extracts.
2. Look for the Latin name of the species, such as Crataegus oxyacantha, and be wary of products labeled tejocote root.
3. Check for a lot number and an independent testing seal; our guide to third-party tested supplements explains what seals cover.
4. Read the warnings panel, follow the label, and ask your cardiologist or pharmacist before use if you take any heart or blood pressure medicine.

Frequently Asked Questions

Questions about a label? Contact us or read our Buyer’s Guide. Follow the label and ask a healthcare provider before starting any supplement, especially if you take medicines. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Last reviewed October 2026.

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