Cauliflower, cabbage, broccoli, savoy cabbage, kale, Brussels sprouts and many other vegetables are all the exact same plant, Brassica oleracea. The only difference is how they are cultivated¹⁾.

Today we have over 5,000 different types of potatoes. However, they all are derived from the original species of wild potatoes from a small region of the Andes²⁾. All ancestral potatoes contain high levels of the glycoalkaloids toxin, and eating them in high quantities could lead to paralysis and even death. Andean inhabitants ate the potatoes with a clay sauce, which helped to neutralize toxins and allowed the domestication of potatoes around 7,000 to 10,000 years ago³⁾. Even today's potatoes contain small amounts of toxins, but they are negligible to human health. However, when raised or stored incorrectly, they can still become poisonous.

Tomatoes are fruits⁴⁾, specifically a edible berry. Tomatoes (Solanum lycopersicum) are closely related to potatoes (Solanum tuberosum) and Eggplant (Solanum melongena), however we eat different parts of those plants (tubers vs fruits)⁵⁾. As other members of Solanum family, also tomatoes contain toxines, including tomatine and solanine, however amounts are very low.