Health effects with consumption of the flax lignan secoisolariciresinol diglucoside

Abstract

Flaxseed is the richest source of the lignan secoisolariciresinol diglucoside (SDG). After ingestion, SDG is converted to secoisolariciresinol, which is further metabolised to the mammalian lignans enterodiol and enterolactone. A growing body of evidence suggests that SDG metabolites may provide health benefits due to their weak oestrogenic or anti-oestrogenic effects, antioxidant activity, ability to induce phase 2 proteins and/or inhibit the activity of certain enzymes, or by mechanisms yet unidentified. Human and animal studies identify the benefits of SDG consumption. SDG metabolites may protect against CVD and the metabolic syndrome by reducing lipid and glucose concentrations, lowering blood pressure, and decreasing oxidative stress and inflammation. Flax lignans may also reduce cancer risk by preventing pre-cancerous cellular changes and by reducing angiogenesis and metastasis. Thus, dietary SDG has the potential to decrease the incidence of several chronic diseases that result in significant morbidity and mortality in industrialised countries. The available literature, though, makes it difficult to clearly identify SDG health effects because of the wide variability in study methods. However, the current evidence suggests that a dose of at least 500 mg SDG/d for approximately 8 weeks is needed to observe positive effects on cardiovascular risk factors in human patients. Flaxseed and its lignan extracts appear to be safe for most adult populations, though animal studies suggest that pregnant women should limit their exposure. The present review discusses the potential health benefits of SDG in humans, with supporting evidence from animal studies, and offers suggestions for future research. Secoisolariciresinol diglucoside: Flax lignans: Health benefitsInvestigations into the health effects of whole flaxseed or flaxseed products (for example, defatted flaxseed meal, flaxseed extracts) in human clinical trials and animal models have shown beneficial changes in blood lipid profiles (1,2) and protection against some types of cancer (3,4) . However, such studies cannot reveal to which flaxseed component(s) the benefits can be attributed, as flaxseed contains at least three components that are of health interest: soluble fibres or mucilage (about 6 % of dry weight) (5) ; high amounts of a-linolenic acid, an n-3 PUFA (about 20 % of dry weight) (6) ; and the plant lignan secoisolariciresinol diglucoside (SDG, about 1 % of dry weight) (7) . Flaxseed also contains small amounts of other lignans, namely pinoresinol, lariciresinol and matairesinol (8) , and although SDG is the predominant lignan, the others may also contribute to health effects.Flaxseed is the richest source of SDG (9) ; however, the amount of SDG in flaxseed varies between different cultivars and in most studies that examined the health effects of flaxseed or its products, the concentration of lignans was not determined. With the development of HPLC technology, SDG can be extracted from flaxseed and its SDG content determined (7) . Subsequent studies...

Effect of bovine ABCG2 polymorphism Y581S SNP on secretion into milk of enterolactone, riboflavin and uric acid

“…Milk from cows fed with whole flaxseed and flaxseed meal supplements or white clover grass silages have been reported to have greater concentrations of enterolactone (Steinshamn et al, 2008;Petit et al, 2009). Enterolactone possesses antioxidant activity and dietary intake of lignans, and their derivatives, as part of a healthy diet, have been associated with protection against cardiovascular disease, diabetes and metabolic syndrome, cancer, oxidative stress and inflammation (Adolphe et al, 2010). Recently, enterolactone has been identified as a substrate of the human and murine abcg2 (Miguel et al, 2014).…”

Effect of Consumption of Ground Wholeseed Flax on Human Blood Traits

“…In addition, flaxseed also contains small amounts of other lignans, namely pinoresinol, lariciresinol, and matairesinol (Zhang et al, 2008). Even though secoisolariciresinol diglucoside is the predominant lignin in flaxseed, other minor lignans may also contribute to improved health benefits (Adolphe et al, 2010). These observations lead us to suggest that research to characterize positive health effects of flaxseed ingestion would need to consider seed components and gender of human subjects.…”

Formulation and Sensory Evaluation of Gluten-Free Muffins Containing Flax

“…These compounds have been shown to have anti-cancer effects in estrogenrelated cancers (Thompson, Robb, Serraino, & Cheung, 1991). They are able to block cellular pathways that lead to the production of mutated cells and are also able to inhibit protein synthesis that leads to metastasis of cancer in different types of tissue including breast, colon, ovary, and prostate (Adolphe, Whiting, Juurlink, Thorpe, & Alcorn, 2010 While both of the essential fatty acids, alpha-linolenic and linoleic acids, are important in the diet, an increasing body of evidence is suggesting that the Western diet receives an excess amount of linoleic acid and quantities of alpha-linolenic acid are too low. In the Paleolithic Age, these essential fatty acids were consumed in equal amounts, but as dietary practices have changed (even over the past one hundred fifty years), a substantial change in ratio has occurred (Simopoulos, 1996).…”

“…The cancerous cells can then be destroyed by the immune system. They can also prevent the metastasis of cancer cells to different tissues and organs (Adolphe, et al, 2010). Thompson and Cunnane (2003) noted increased urinary excretion of enterolactone and enterodial, which was directly related to dietary intake.…”