What are pyrrolizidine alkaloids and why are they a risk?
Pyrrolizidine alkaloids (PAs) are naturally occurring plant toxins found in borage and other herbs. These compounds can be hepatotoxic, meaning they are toxic to the liver, especially when consumed in large quantities or over an extended period. The PA content can vary depending on the plant part used (leaves or flowers), the plant's maturity, and growing conditions.
Borage leaves vs. flowers
Research indicates that PA levels are significantly higher in borage leaves and young plant parts compared to the flowers. While flowers are sometimes used for a milder tea, PA concentrations in any part of the plant are a serious consideration. This is why regulatory bodies in some countries have restricted or banned borage for food consumption. For context, commercial borage seed oil is processed to remove PAs and is generally considered safe, but this does not apply to homemade herbal teas made from the leaves or flowers.
Who should strictly avoid borage tea?
Because of the potential for liver damage, certain individuals should never consume borage tea. This includes:
- Pregnant and breastfeeding women. PAs can cross the placenta and pass into breast milk, posing a risk to the baby.
- People with pre-existing liver conditions. Consuming borage can worsen liver disease.
- Those taking medications that affect the liver. Borage can interact with drugs metabolized by the liver, including certain medications for seizures and blood clotting.
- Children under 12. Children are more sensitive to toxins, and their developing livers are particularly vulnerable to PA exposure.
Potential side effects of borage tea
Beyond the risk of liver toxicity, borage tea can cause other side effects, especially with excessive consumption. Some commonly reported issues include:
- Gastrointestinal distress: Nausea, bloating, cramping, and indigestion are possible side effects.
- Bleeding risk: Due to its gamma-linolenic acid (GLA) content, borage oil and potentially tea may slow blood clotting. This is a concern for people with bleeding disorders or those taking anticoagulant medications.
- Allergic reactions: Although rare, some individuals may experience skin rashes, itching, or swelling.
- Seizures: In one isolated case, a woman experienced seizures after taking high doses of borage oil for a short period. While this was linked to oil, the risk with high consumption of any borage product should be noted.
How to prepare borage tea with minimal risk (for informed adults only)
For those who understand the risks and are not in a high-risk group, careful preparation can minimize, but not eliminate, risk. It is crucial to remember that minimizing risk does not mean zero risk, especially with long-term use. Experts advise intermittent and limited use.
Preparing a cautious infusion
- Harvest young leaves or use flowers only: Younger leaves contain fewer PAs than mature ones, but flowers are the safest plant part to use.
- Use whole leaves: Studies suggest that infusing intact leaves releases fewer PAs into the tea than using ground leaves.
- Steep briefly: Steep dried or fresh plant material in just-boiled water for 5-10 minutes.
- Avoid boiling: Boiling the herb directly can increase the release of compounds and should be avoided.
Borage Tea Safety vs. Commercial Borage Seed Oil
| Feature | Borage Tea (Leaves/Flowers) | Commercial Borage Seed Oil | Key Takeaway |
|---|---|---|---|
| Source | Infusion of leaves and/or flowers of the borage plant | Oil extracted from the seeds of the borage plant | Different parts of the plant are used |
| Pyrrolizidine Alkaloids (PAs) | Contain PAs which can cause liver damage with regular consumption. | Certified PA-free during processing. | Seed oil is significantly safer regarding PA risk |
| Gamma-Linolenic Acid (GLA) | Contains some GLA, but less concentrated. | High concentration of GLA. | GLA is the primary beneficial compound in the oil |
| Safety Profile | Potentially unsafe, especially with long-term or high-dose use. | Considered safe when certified PA-free. | Tea has a higher risk due to PA content |
| Recommended Use | Intermittent, cautious use for informed adults only. | Commonly used as a dietary supplement. | Seed oil is a more reliable and safer source for therapeutic effects |
Conclusion: Navigating borage tea with caution
While borage has a history in traditional medicine and some cultures still use it, the modern understanding of its safety profile, particularly regarding liver-toxic pyrrolizidine alkaloids, urges caution. Borage tea, especially when made from leaves, is not safe for long-term or regular consumption due to the risk of liver damage. High-risk individuals, including pregnant women, those with liver issues, and children, should avoid it entirely. For others, limiting consumption to small, occasional doses prepared cautiously is key, with the recognition that no herbal tea containing PAs can be considered 100% risk-free. A much safer alternative for gaining borage's therapeutic benefits is through commercial, PA-free borage seed oil. Always consult a healthcare professional before incorporating any new herbal remedy into your routine to ensure it is appropriate for your individual health status.
