|MadSci Network: Botany|
From a plant perspective, caffeine is a secondary compound, meaning that it is not involved in basic metabolism, like primary compounds such as starch, DNA, amino acids, and chlorophyll. Thus caffeine is not found in substantial amounts in all plants. At least 100 species of plants do contain caffeine. Caffeine is found in large amounts mainly in certain human beverages obtained from seeds or leaves. I am not aware of high levels of caffeine in any common vegetables and nonbotanical fruits. The main sources of caffeine in the human diet are coffee (from coffee seeds) and soft drinks such as colas (from cola nut seeds and also from added caffeine). Other sources include tea (leaves), chocolate (cacao seeds), guarana (seeds) and yerba mate (leaves). Added caffeine in foods is obtained as a byproduct from the preparation of decaffeinated coffee. Many processed foods containing coffee or chocolate also contain caffeine including frozen dairy desserts, baked goods, gelatin, puddings and pie fillings, and soft candy. Several headache pills and pep pills to keep you from falling asleep also contain caffeine. See the second website for amounts of caffeine present in medicines and foods. References Plant Caffeine Sources Caffeine Content of Foods and Drugs Caffeine CAFFEINE JITTERS: SOME SAFETY QUESTIONS REMAIN Cola nut Discovering the Sweet Mysteries of Chocolate Plant Secondary Compounds
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