Kava's Anti-Cancer Potential: Key Review Findings

Kava's Anti-Cancer Potential: Key Review Findings

Quick Summary: A 2019 systematic review examined how kava plant compounds might fight cancer by slowing cell growth and triggering cell death. Out of 39 studies, most showed promising anti-cancer effects, especially for skin and other surface cancers, but human trials are still needed. Key ingredients like flavokavain B and A stood out for boosting helpful proteins that kill cancer cells.

What the Research Found

Researchers reviewed lab and animal studies on kava's active parts, called kavalactones, chalcones, and flavanones. These come from the roots of the Piper methysticum plant, used traditionally in Pacific islands as a relaxing drink. The big takeaway? Kava compounds often stop cancer cells from multiplying and push them to die naturally—a process called apoptosis.

• Strong anti-growth effects: 32 out of 39 studies showed kava parts slowed cancer cell spread, mainly by halting the cell cycle (like putting a pause button on cell division).
• Top performers: Flavokavain B (most studied) and flavokavain A ramped up pro-death proteins like Bax and caspase-3, while dialing down survival proteins like Bcl-2. This imbalance helps kill off cancer cells.
• Blood vessel blocking: In several tests, higher doses of these compounds cut down new blood vessel growth that tumors need to survive— a dose-dependent effect, meaning more compound led to stronger results.
• Cancer types tested: Covered 26 types, with a focus on epithelial cancers (like those in skin, mouth, or lungs) in 32 studies. Only 6 looked at mesenchymal cancers (like bone or muscle), and just one study tested oral squamous cell carcinoma (a common mouth cancer).

Overall, kava looks promising for preventing or treating certain cancers, especially surface ones, but results varied due to different testing methods.

Study Details

This was a systematic review—a roundup of existing research up to April 2018—from databases like EMBASE, MEDLINE, and Web of Science. It pulled together 39 papers, but no new experiments were done.

• Who was studied: Not real people—mostly lab-grown cancer cells (in vitro, 32 studies) and rodents like mice (animal models, 13 studies). No human participants.
• How long: The review covered studies of varying lengths, from hours in cell tests to weeks in animals, but didn't track overall timelines.
• What they took: No standard doses, as methods differed. Cells got direct kava extracts; animals received injections or oral doses of compounds like flavokavain B. Amounts varied widely, often scaled to body weight in animals.

What This Means For You

If you're curious about natural ways to support cancer prevention, kava's lab results suggest its compounds could act like a natural brake on tumor growth, especially for epithelial cancers. For example, if you have a family history of skin or mouth cancer, this might spark interest in future kava-based therapies. But don't start sipping kava tea for cancer treatment— these are early findings from cells and animals, not proven for humans. Talk to your doctor before trying kava supplements, as they can relax you but might affect your liver. This research highlights why more human studies could lead to safer, natural add-ons to chemo or prevention plans.

Study Limitations

While exciting, this review has gaps that mean we can't jump to real-world use yet.

• Mostly lab-based: 82% of studies used cells in dishes, and only a third involved animals—no human data, so effects in people are unknown.
• Varied approaches: Different cancers, doses, and methods made it hard to compare results directly.
• Limited mouth cancer info: Just one study on oral squamous cell carcinoma, so we need more to know if kava helps there.
• Safety not fully checked: Past reports link kava to liver risks, but this review didn't dive deep into that. Stick to proven treatments and avoid self-dosing.