Mistletoe is a semiparasitic plant associated with winter tradition, but it poses a significant health hazard if consumed. The answer to whether you can eat mistletoe is an unequivocal no, as the entire plant contains compounds highly toxic to humans and pets. Ingestion of any part of the plant, including the white berries or the leaves, can lead to poisoning and requires immediate medical attention. The toxicity stems from potent natural chemicals that interfere with fundamental biological processes inside the body’s cells.
Identifying the Toxic Components
The danger of mistletoe ingestion comes from its concentration of toxic proteins, primarily a group of compounds known as lectins and viscotoxins. Mistletoe lectins, sometimes referred to as viscumin, are classified as Type 2 ribosome-inactivating proteins (RIPs). These compounds halt protein synthesis within the cells they enter, which leads to cell death through a process called apoptosis.
Viscotoxins are smaller, heat-stable polypeptides that act through a different mechanism, directly disrupting cell membranes. They cause rapid cell lysis, or necrosis, by binding to membrane phospholipids and creating pores that destroy the cell’s structural integrity. These substances are present throughout the plant, but the highest concentrations are often found in the leaves and berries.
The Danger of Different Mistletoe Species
Mistletoe’s toxicity can vary significantly depending on the species and geographical location, which often creates public confusion regarding its danger. The two most common varieties are the North American species, Phoradendron serotinum, and the European species, Viscum album. The primary toxin in the North American variety is phoratoxin, and its ingestion typically results in less severe gastrointestinal upset.
The European species, Viscum album, is considered far more potent because of its viscotoxin content. Ingesting this variety can lead to serious systemic poisoning, potentially affecting the cardiovascular and nervous systems. All mistletoe plants should be treated as dangerous and never consumed or brewed into a tea. The risk is especially high for small children and pets, where a small amount constitutes a much larger relative dose.
Symptoms of Ingestion and Emergency Action
Symptoms following mistletoe ingestion can range from mild gastrointestinal distress to severe systemic reactions, often developing within hours. The most common initial signs include nausea, vomiting, abdominal pain, and diarrhea. If a larger quantity of the more toxic European species is involved, the symptoms can escalate quickly.
More severe poisoning can manifest as blurred vision, lethargy, and drowsiness, indicating effects on the central nervous system. Further complications may include a slow heart rate, known as bradycardia, or seizures. The speed of medical intervention is paramount, as the toxins directly attack cellular function in tissues with high cellular turnover, such as the gastrointestinal tract.
If any part of the mistletoe plant is swallowed, immediate action is required. Call the national toll-free Poison Help hotline at 1-800-222-1222 from anywhere in the United States. Provide information about the person’s age, weight, and the type and amount of plant ingested to help professionals give accurate instructions. Do not attempt to induce vomiting unless specifically advised by a healthcare provider or Poison Control.
Clarifying Medicinal Uses
The plant’s known toxicity is sometimes confused with the historical and modern use of mistletoe extracts in a regulated medical context. Specific extracts derived almost exclusively from the European species, Viscum album, are used in certain European countries as a complementary cancer therapy. These preparations are highly controlled and administered through subcutaneous or intravenous injection, not consumed orally.
The therapeutic benefit is thought to come from the controlled delivery of lectins and viscotoxins, which can stimulate the immune system and potentially induce cell death in tumors. The existence of these prescription-only extracts, such as Iscador or Helixor, does not suggest the raw plant is safe to eat or use in home remedies. Consuming the raw plant results in an uncontrolled dose of toxins, which is entirely different from the carefully calibrated, injected doses used in a clinical setting.