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Chia is grown commercially for its seed, a food that is rich in omega-3 fatty acids α-linolenic acid (ALA).
A ounce (28 g) of dried chia seeds contain 9% of the Daily Value for protein (4g), 13% fat (9g) (57% of which is ALA) and 42% dietary fiber (11g), based on a daily intake of 2000 calories. The seeds also contain the essential minerals phosphorus, manganese, calcium, potassium and sodium.
Taking this supplement will not affect you in a negative way, inspite of you having coliac disease.