Antinutrients
Compounds naturally present in plants that reduce the absorption or use of certain nutrients, such as phytic acid (rice, pulses), tannins (tea) or enzyme inhibitors (raw pulses).
Antinutrients are a plant’s defence strategy against predators and parasites. The main ones:
- Phytic acid: binds minerals (calcium, zinc, iron, magnesium) and makes them less bioavailable. Found in uncooked pulses, seeds and brown rice
- Tannins: bind to proteins and reduce their digestion. Tea, cocoa, raisins
- Protease inhibitors: block digestive enzymes. Raw pulses (inactivated by cooking)
- Lectins: proteins that are toxic in high doses. Peanuts, raw beans (cooking removes them)
- Goitrogens: interfere with the thyroid. Raw broccoli and cabbage in excess
- Saponins: form foam and irritate the gut. Pulses, oats
A fresh angle: antinutrients are not bad at all; it is a question of quantity and preparation. Cooking, soaking and sprouting drastically reduce most antinutrients. A bowl of cooked lentils has almost zero enzyme inhibitors.
The real risk: eating very large quantities of uncooked phytates (raw rice, for example) can create deficiencies. But eating cooked brown rice? Zero risk.
A marketing trap: “raw food” evangelists urge eating raw pulses or raw sprouts to “preserve enzymes”, which increases antinutrients. Well-judged cooking reduces antinutrients AND improves the bioavailability of certain nutrients (for example, cooked tomatoes release more lycopene).