| doreen T |
Sun, Jun-05-05 16:21 |
Yep, toasting the seeds at a low heat (no more than 250°F) will destroy the glycosides AND still preserve the omega-3 oil. FWIW, cyanogenic glycosides are found in the seed, but not in the oil.
Cyanogenic glycosides must first be metabolised to thiocyanate before they're actually harmful.
http://www.flaxcouncil.ca/FlaxPrimer_Chptr11.pdf
Quote:
Cyanogenic Glycosides
Cyanogenic glycosides are a group of natural substances found in plants that release cyanide, a poisonous compound, when degraded by enzymes or organic acids (304,305). Thousands of plants produce cyanogenic compounds (306), including several agronomically important crops such as cassava (also called tapioca and manioc), lima beans, bamboo shoots, sorghum, flax, apples and stone fruits like peaches, plums, cherries and apricots. Other sources of dietary cyanide include vitamin B12 (cyanocobalamin), an essential vitamin required for cell growth and the health of red blood cells, and thiocyanates, which are found naturally in milk, beer and green vegetables. Thiocyanate is a breakdown product of the cyanogenic glycosides and of glucosinolates found in millet and in cruciferous vegetables like cabbage, broccoli, cauliflower, kale, mustard, turnip, radish, and horseradish (307,308).
Thiocyanate is a goitrogen, meaning that it blocks the uptake of iodine by the thyroid gland (308). When the diet is overly rich in goitrogens, the thyroid gland swells to trap as much iodine as possible, forming a goiter or lump in the neck (309). There is no evidence that eating flax produces symptoms of goiter. Goiter is not a health problem where iodine intake is adequate (303,310), and it is rare in North America. [Goiter occurs mainly in Asia and Africa, and in 96% of cases, it is due to iodine deficiency, not to the overconsumption of plant goitrogens (309).] Iodine deficiency disorders like goiter have been virtually eliminated in the United States through the iodization of salt (311). In Canada, table salt has been iodized since the 1930s to eliminate endemic goiter in inland regions where dietary iodine was inadequate (310). The addition of iodine to table salt is required in Canada and permitted in the United States.
Furthermore, eating baked goods containing flax appears to have little effect on urinary thiocyanate levels. In a Canadian study, urinary thiocyanate levels were not greater in healthy women who ate muffins containing flax every day for four weeks (55). This finding suggests that serum thiocyanate levels and, hence, risk of goiter, were not increased.
Populations most likely to experience health problems from cyanogenic glycosides have poor quality diets rich in cassava and also low energy (calorie) and iodine intakes. By comparison, North Americans are well nourished and eat a variety of foods daily. In healthy people who eat varied diets, the body can eliminate the potentially harmful compounds found in plants (312).
Consumption of moderate amounts of flax (for example, 1–2 tbsp) daily is not likely to pose a health problem for North Americans who have adequate intakes of protein and iodine. In several clinical studies, volunteers ate muffins containing 50 g (5–6 tbsp) of ground flax daily for up to six weeks without ill effects. Muffins made with ground flax showed no trace of the cyanogenic glycosides, suggesting that cooking destroyed the enzyme that metabolizes the cyanogenic glycosides (55).
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hth :rose:
Doreen |
