# Chocolate (Theobroma cacao)

*Nahuatl *cacahuatl*; *cacao**

**Known today as.** The fermented, dried, and roasted seeds of *Theobroma cacao*, drunk by the Maya and the Aztecs before Spanish conquistadors met it in 1519.

Kind: Food & Drink

## What was it used for?

Nourishing and restoring, for the consumptive and the weak; and, by the reports of the Indies, a provoker of lust.

## What does modern science say?

Its flavanols have small effects on blood pressure in trials; it is a food.

## Pharmacognosy and toxicology

- **theobromine**: 
- **caffeine**: 
- **epicatechin**: the flavanol

**Mechanism.** Theobromine is a mild heart stimulant and, more weakly than caffeine, blocks the adenosine receptors; in trials, chocolate and cocoa improved the flow-mediated dilatation of the arteries. Dogs clear theobromine slowly, with a half-life of 17.5 hours, and some 200 g of the richest dark chocolate gives a 10 kg dog an even chance of a lethal dose.

**Dose.** The median lethal dose of theobromine for dogs is 100–200 mg per kilogram.

**Standing.** A food; in 2013 the European Union authorised the claim that cocoa flavanols help maintain endothelium-dependent vasodilation, which contributes to healthy blood flow.

## What lore surrounds it?

Whether chocolate broke the Church’s fast was argued in Spain and the Indies, as Stubbe reported in 1662, and the dispute ran on although popes, Pius V and Benedict XIV among them, gave the opinion that it did not.

## What did the older authorities say?

**Antonio Colmenero de Ledesma.** Wrote in 1631 on whether it was hot or cold in the Galenic sense, and concluded that it was both: its parts were of different temperaments.

**Henry Stubbe.** Praised it in *The Indian Nectar* (1662).

## Sources

- Colmenero de Ledesma, A. (1631). *Curioso tratado de la naturaleza y calidad del chocolate*.
- Stubbe, H. (1662). *The Indian Nectar*.
- “History of chocolate.” *Wikipedia* (read 2 October 2026).
- “Cocoa bean.” *Wikipedia* (read 2 October 2026).
- “Theobromine.” *Wikipedia* (read 2 October 2026).
- “Catechin” (Epicatechin). *Wikipedia* (read 2 October 2026).
- European Commission (2013). Commission Regulation (EU) No 851/2013 of 3 September 2013 authorising certain health claims made on foods. *Official Journal of the European Union* L 235: 3–7.
- “Theobromine poisoning.” *Wikipedia* (read 2 October 2026).
- Hooper, L., et al. (2012). “Effects of chocolate, cocoa, and flavan-3-ols on cardiovascular health.” *American Journal of Clinical Nutrition* 95.

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*Chocolate.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-10-01. The Thinking Press. https://thethinkingpress.org/materia-medica/chocolate

Historical description, not medical advice.