Poisonous / Toxic Tomatoes
While most modern cultivated tomatoes are safe and widely enjoyed, the idea of "poisonous tomatoes" has historical, scientific, and cultural roots. Here’s a comprehensive look at the topic:
1. Historical Fear of Tomatoes
"Poison Apples" Myth:
In the 16th and 17th centuries, when tomatoes were introduced to Europe from the Americas, they were associated with danger and poison.
As members of the nightshade family (Solanaceae), tomatoes were grouped with plants like deadly nightshade (belladonna) and jimsonweed, which are highly toxic.
Wealthy Europeans, who ate off pewter plates, sometimes developed lead poisoning after eating tomatoes. The tomato’s high acidity could leach lead from the plates, leading to illness or death, reinforcing the idea that tomatoes were poisonous.
2. Scientific Basis for Tomato Toxicity
Tomatine in Green Tomatoes:
Unripe green tomatoes and tomato leaves contain tomatine, a glycoalkaloid compound that can be toxic in large amounts.
Symptoms of tomatine poisoning might include:
Nausea
Vomiting
Diarrhea
Headaches
Dizziness
However, the amount of tomatine in modern tomatoes is generally too low to cause harm unless consumed in very large quantities.
Solanine:
Tomatoes also contain solanine, another alkaloid common in the nightshade family (also found in potatoes). Solanine levels are higher in leaves and stems than in the fruit.
Eating large amounts of tomato leaves, stems, or unripe fruit could theoretically lead to mild poisoning, but cases are extremely rare.
3. Poisonous Parts of the Tomato Plant
Leaves, Stems, and Flowers:
These parts of the plant contain higher concentrations of tomatine and solanine, making them more likely to cause adverse effects if ingested.
While not typically consumed, pets (especially cats and dogs) may experience poisoning if they chew on these parts of the plant.
4. Cultural and Regional Beliefs
Superstition and Myths:
In some cultures, tomatoes were thought to be associated with witchcraft or evil spirits, further cementing their reputation as "dangerous."
In Italy, early on, tomatoes were nicknamed "mala insana" (mad apple) because of their feared effects on health.
Medicinal Use:
Ironically, tomatoes were also believed to have medicinal properties in some regions, used as remedies for ailments despite their feared toxicity.
5. Modern Concerns and Misconceptions
Tomatoes and Nightshade Sensitivity:
Some people believe tomatoes contribute to inflammation or exacerbate autoimmune disorders due to their solanine content. While scientific evidence is limited, some individuals avoid tomatoes for this reason.
Toxicity in Animals:
Tomato plants are toxic to many pets (dogs, cats, and horses) due to solanine and tomatine. Even small amounts can lead to symptoms such as:
Drooling
Vomiting
Diarrhea
Lethargy
6. Unripe Tomatoes in Cooking
Green Tomatoes Are Not Always Poisonous:
In many cuisines, unripe green tomatoes are used safely in dishes, such as fried green tomatoes or pickled tomatoes. Cooking significantly reduces tomatine levels.
However, eating large quantities of raw green tomatoes might still cause mild gastrointestinal upset in sensitive individuals.
7. Genetically Engineered or Wild Varieties
Wild Tomatoes:
Some wild species of tomatoes, native to South America, may have higher levels of alkaloids than cultivated varieties, making them potentially toxic.
Heirloom Varieties:
Older tomato strains may retain slightly higher tomatine levels than modern commercial varieties, but they are generally safe to eat.
Conclusion
Modern cultivated tomatoes are overwhelmingly safe, but their historical association with poison comes from a mix of legitimate alkaloid toxicity in their leaves and stems, as well as myths and superstitions. While unripe tomatoes and parts of the plant can contain compounds that are mildly toxic, they rarely pose a serious threat unless consumed in large quantities.
