Demystifying the Pawpaw: American Pawpaw vs. Tropical Papaya
Before diving into the risks, it's crucial to clarify a common point of confusion: the American pawpaw (Asimina triloba) is not the same as the tropical fruit papaya (Carica papaya). The American pawpaw is the largest edible fruit native to the United States and Canada, known for its unique flavor profile, often described as a mix of banana, mango, and pineapple. While papaya can also cause side effects like digestive issues in some people, the specific toxic compounds and risks associated with the American pawpaw are unique to its plant family, Annonaceae. It is the American pawpaw that contains annonacin, a potent neurotoxin found throughout the plant.
The Source of Pawpaw Sickness: Annonaceous Acetogenins
The primary culprits behind pawpaw toxicity are a class of compounds called annonaceous acetogenins, with annonacin being the most notable. These compounds are present in varying concentrations in different parts of the pawpaw tree.
- Seeds, Skin, and Leaves: These parts contain the highest concentrations of annonacin and are considered toxic and should never be consumed.
- Unripe Fruit: Unripe pawpaw fruit also contains higher levels of annonacin than ripe fruit and should be avoided.
- Ripe Fruit Pulp: The ripe, yellow fruit pulp is generally considered safe for consumption in moderation. However, it is not completely free of annonacin.
Acute Risks from Pawpaw Consumption
Even when eating only the ripe pulp, some individuals may experience immediate, adverse reactions. These acute symptoms often appear shortly after consumption and can be quite unpleasant.
- Gastrointestinal Distress: The most common adverse reaction is a form of stomach upset, which can include nausea, stomach cramps, and vomiting. This can occur in sensitive individuals even when consuming small amounts of ripe fruit. Anecdotal reports also suggest cooking or dehydrating the fruit can elevate the risk of these acute reactions.
- Allergic Reactions: Some people have a sensitivity or allergy to pawpaw, which can manifest as hives, skin rashes (contact dermatitis), or other allergic symptoms. The Lewis and Clark expedition reportedly experienced cases of contact dermatitis after handling the plant. For this reason, it's wise to start with a small amount if you are a first-time consumer.
Chronic Concerns: The Neurotoxicity Factor
Beyond immediate sickness, long-term and high-level consumption of annonacin raises more serious health concerns. Annonaceous acetogenins are known neurotoxins that can damage nerve cells in the brain.
- Atypical Parkinsonism: Research, particularly involving relatives of the pawpaw like soursop in the Caribbean, has linked high, chronic consumption of annonacin to a form of atypical Parkinsonism. While the exact risk level for moderate pawpaw consumption is not well understood due to limited human studies, it is a significant enough concern that some medical professionals advise against frequent or high intake, especially for individuals with a family history of Parkinson's.
Comparison of American Pawpaw and Papaya
To further clarify the difference, the following table compares key characteristics and potential risks of American Pawpaw and the tropical fruit Papaya.
| Feature | American Pawpaw (Asimina triloba) |
Tropical Papaya (Carica papaya) |
|---|---|---|
| Origin | Native to eastern North America | Native to Mexico and Central America |
| Toxic Compound | Annonacin (acetogenin) | Papain and latex (in unripe fruit) |
| Toxic Plant Parts | Seeds, skin, leaves, bark; higher concentration in unripe fruit | Latex in unripe fruit; can cause allergies |
| General Consumption Risk | Gastrointestinal upset, allergies, potential long-term neurotoxicity from high intake | Digestive issues, allergies (especially in latex-sensitive people), and uterine stimulation risk during pregnancy (unripe fruit) |
| Safe Consumption | Ripe pulp only, in moderation | Ripe fruit is generally safe; unripe fruit is riskier |
Safe Handling and Consumption Practices
For those who wish to enjoy the unique flavor of the American pawpaw, following specific guidelines is essential to minimize risk:
- Only eat ripe fruit: A ripe pawpaw will feel soft, similar to a peach, and have a strong, sweet aroma. Unripe fruit is more likely to cause sickness.
- Avoid seeds and skin: These parts contain the highest levels of annonacin and should be completely removed before eating.
- Limit consumption: While the occasional, fresh, ripe pawpaw is considered low-risk, consistently eating large quantities, especially over a long period, is not advised due to potential neurotoxic effects.
- Wash thoroughly: Wash your hands after handling the skin or seeds to prevent any contact with the irritants that can cause dermatitis.
- Beware of cooking or drying: Anecdotal evidence suggests that heating or dehydrating the fruit may increase its toxicity. It is best to enjoy the fruit fresh and raw.
- Listen to your body: If you experience nausea, vomiting, or other symptoms after eating pawpaw, decrease or discontinue consumption. Some individuals are simply more sensitive than others.
Conclusion
So, can you get sick from eating paw paw? Yes, it is possible, particularly if you consume the toxic seeds, skin, or unripe fruit. Even with ripe pulp, moderate intake is recommended due to the presence of annonacin. While the risk of serious neurological issues from occasional, fresh consumption is considered low, it is a risk that consumers should be aware of, especially given the lack of extensive research on long-term human intake. For most people, enjoying a fresh, ripe pawpaw in moderation is a safe way to experience this unique native fruit. But for others, especially pregnant women and those with digestive or neurological sensitivities, it's a food best approached with caution or avoided entirely.
An excellent resource for learning more about the properties and potential effects of American pawpaw is the Memorial Sloan Kettering Cancer Center, which provides information on its compounds and side effects.
