Anti-nutritional factor

Antinutrients are natural or synthetic compounds that interfere with the absorption of nutrients. Nutrition studies focus on these antinutrients commonly found in food sources and beverages.

Phytic acid has a strong binding affinity to minerals such as calcium, magnesium, iron, copper, and zinc. This results in precipitation, making the minerals unavailable for absorption in the intestines. Phytic acids are common in the hulls of nuts, seeds and grains and of great importance in agriculture animal nutrition and eutrophication wise due to the mineral chelation and bound phosphates released in to the environment. Without the need to use phytate (but also nutrient) reducing milling, the amount of phytic acid is commonly reduced in animal feeds by adding histidine acid phosphate type of phytases to them.

Protease inhibitors are substances that inhibit the actions of trypsin, pepsin and other proteases in the gut, preventing the digestion and subsequent absorption of protein. For example, Bowman–Birk trypsin inhibitor is found in soybeans.

Lipase inhibitors interfere with enzymes, such as human pancreatic lipase, that catalyze the hydrolysis of some lipids, including fats. For example, the anti-obesity drug orlistat causes a percentage of fat to pass through the digestive tract undigested.

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