No evidence of hypoglycemia or hypotension in older adults during 6 months of flax lignan supplementation in a randomized controlled trial: A safety evaluation

Abstract

Context: The natural health product, BeneFlax, is a standardized flaxseed [Linum usitatissimum L. (Linaceae)] lignan enriched product with evidence of product quality and known quantity of the bioactive component, lignan. The acceptance of this natural health product for its various health benefits requires greater evidence of its safety in the general population. Objective: We determined whether flaxseed lignan causes clinical hypoglycemia or hypotension in healthy older adults as an important aspect of safety. Materials and methods: Participants aged 49-87 years were randomized in a double-blind trial to receive flaxseed lignan (543 mg/day in BeneFlax) or placebo while completing a 6-month walking program. The 94 participants who completed the study were stratified by age (565 years versus !65 years) and treatment category to determine whether older adults were more susceptible to adverse effects. Results: After 6 months of treatment, average plasma glucose level (5.4 AE 0.6 mmol/L), systolic blood pressure (127 AE 14 mm Hg), and diastolic blood pressure (80 AE 9 mm Hg) were within normal clinical range. Controlling for sex and body mass index covariates resulted in no observed differences between plasma glucose or blood pressure measurements between treatment or age groups (p40.05). No incidents of hypoglycemia or hypotension were observed during BeneFlax treatment, suggesting that 543 mg falls at or below the no observable adverse effect level (NOAEL). Discussion and conclusion: These data suggest the flaxseed lignan product BeneFlax does not pose a risk of hypoglycemia or hypotension in healthy adults aged 49-87 years.

Stability of bioactives in flaxseed and flaxseed-fortified foods

“…Other studies have demonstrated improved glycemic control (Pan et al, 2007), decreased blood glucose levels (Zhang et al, 2008), reduced CRP (Hallund, Tetens, Bugel, Tholstrup, and Bruun, 2008;) and a mild attenuation in DBP (Cornish et al, 2009) with a lignan-supplemented diet. An additional study noted that Beneflax, a lignan supplement containing 543 mg/day of flaxseed lignan per tablet (Cornish et al, 2009), does not pose a risk for hypotension or hypoglycemia in healthy older adults (Billinsky et al, 2013).…”

Comparative pharmacokinetics of purified flaxseed and associated mammalian lignans in male Wistar rats

“…Many of these studies have reported no genotoxic, haematological or behavioural changes following consumption of flaxseed or flaxseed products ( 10 – 12 ) . Billinsky et al ( 13 ) reported no evidence of hypoglycaemia or hypotension in healthy older adults when the flaxseed lignan-enriched complex, Beneflax, was administered for 6 months; however, other studies have reported some adverse reactions in special populations such as pregnant and lactating women ( 14 – 16 ) . In general, safety and efficacy data on flaxseed lignans are inadequate.…”

Flaxseed for Hypertension: Implications for Blood Pressure Regulation

“…Recently, a high SDG lignan supplement was assessed for its hypotensive effects in a healthy population >48 years of age [33]. BeneFlax is a commercially available source of SDG lignan that provides 543 mg of SDG in a single tablet.…”