The first unique feature of flax is its high omega-3 fatty acid content. Among all 127 World’s Healthiest Foods, flaxseeds comes out number one as a source of omega-3s! The primary omega-3 fatty acid found in flaxseeds is alpha-linolenic acid, or ALA. The ALA in flaxseed has found to be stable for at least 3 hours of cooking at oven temperatures (approximately 300F/150C), which makes it available after ground flaxseeds have been added to baked goods like muffins or breads.
The second unique feature of flaxseed is its lignans. Lignans are fiber-like compounds, but in addition to their fiber-like benefits, they also provide antioxidant protection due to their structure as polyphenols. The unique structure of lignans gives them a further health-supportive role to play, however, in the form of phytoestrogens. Along with isoflavones, lignans are one of the few naturally occurring compounds in food that function as weak or moderate estrogens when consumed by humans. Among all foods commonly eaten by humans, researchers rank flaxseeds as the number one source of lignans. Sesame seeds come in second, but contain only one-seventh of the total lignans as flaxseeds. To give a few further examples, sunflower seeds contain about 1/350th as many lignans, and cashews nuts contain about 1/475th as many lignans as flaxseeds.
A third unique feature of flaxseeds is their mucilage (gum) content. “Mucilage” refers to water-soluble, gel-forming fiber that can provide special support to the intestinal tract. For example, gums can help prevent the too rapid emptying of the stomach contents into the small intestine, thereby improving absorption of certain nutrients in the small intestine. Arabinoxylans and galactoxylans are included within the mucilage gums found in flaxseeds.
This combination of features—omega-3 fatty acids, high-lignan content, and mucilage gums—is a key factor in the unique health benefits of flaxseeds. The specific areas of health benefit described below all draw in some way from this unique combination of nutrients not found in other commonly eaten nuts or seeds.
Source: the world healthiest food http://www.whfoods.com