# Linum Seed (Linum usitatissimum)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/linum-seed
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-31
**Evidence Score:** 2 / 10
**Category:** Other
**Also Known As:** Linum usitatissimum, flaxseed, linseed, common flax seed, brown flaxseed, golden flaxseed, flax, linseeds, alsike

## Overview

Linum seed (flaxseed) is one of the richest plant sources of alpha-linolenic acid (ALA), an omega-3 fatty acid, and secoisolariciresinol diglucoside (SDG), a lignan that undergoes gut microbial conversion to enterolignans with estrogenic and [antioxidant activity](/ingredients/condition/antioxidant). These bioactives collectively modulate lipid [metabolism](/ingredients/condition/weight-management), [inflammatory](/ingredients/condition/inflammation) cytokine production, and estrogen receptor signaling.

## Health Benefits

• Rich source of omega-3 fatty acids (α-linolenic acid) comprising over 70% of total fatty acids - compositional data only
• Contains high-quality protein with essential amino acids including leucine (6.82g/100g) and lysine (4.18g/100g) - compositional data only
• Provides lignans, particularly secoisolariciresinol diglucoside (SDG) at 610-1300mg/100g concentrated in seed coat - compositional data only
• Source of phenolic acids including p-hydroxybenzoic acid (1719-6454mg/100g) and chlorogenic acid (720-1435mg/100g) - compositional data only
• Contains essential minerals including potassium (7.88-9.12g/kg), magnesium (2.04-2.43g/kg), and zinc (48.30-55.71mg/kg) - compositional data only

## Mechanism of Action

Alpha-linolenic acid (ALA) is elongated and desaturated by FADS1/FADS2 enzymes to EPA and DHA, which compete with arachidonic acid for COX and LOX enzymes, reducing synthesis of pro-inflammatory [prostaglandin](/ingredients/condition/inflammation)s and leukotrienes. The lignan SDG is converted by intestinal bacteria to enterodiol and enterolactone, which act as selective estrogen receptor modulators (SERMs), binding ERα and ERβ with differential affinity and modulating estrogen-dependent gene transcription. Flaxseed mucilage and soluble fiber additionally slow glucose absorption and bind bile acids, upregulating hepatic LDL receptor expression and lowering circulating [LDL cholesterol](/ingredients/condition/heart-health).

## Clinical Summary

A 2015 meta-analysis of 28 RCTs (n=1,702) found whole flaxseed supplementation significantly reduced [LDL cholesterol](/ingredients/condition/heart-health) by approximately 0.21 mmol/L and total cholesterol by 0.39 mmol/L, with strongest effects in postmenopausal women and individuals with dyslipidemia. A separate meta-analysis of 11 RCTs found daily flaxseed consumption reduced systolic blood pressure by 2.85 mmHg and diastolic by 2.39 mmHg. Evidence for cancer risk reduction is preliminary; observational studies associate higher urinary enterolactone levels with reduced breast cancer risk, but RCT confirmation is lacking. Overall evidence quality for cardiovascular outcomes is moderate, while evidence for hormonal and oncologic endpoints remains insufficient for clinical recommendations.

## Nutritional Profile

{"macronutrients": {"protein": "20.0g/100g", "fat": "42.0g/100g", "carbohydrates": "28.0g/100g", "fiber": "27.3g/100g"}, "micronutrients": {"vitamins": {"vitamin_B1": "1.64mg/100g", "vitamin_B6": "0.47mg/100g"}, "minerals": {"calcium": "255mg/100g", "magnesium": "392mg/100g", "phosphorus": "642mg/100g", "potassium": "813mg/100g"}}, "bioactive_compounds": {"omega_3_fatty_acids": {"alpha_linolenic_acid": "22.8g/100g"}, "lignans": {"secoisolariciresinol_diglucoside": "610-1300mg/100g"}}, "bioavailability_notes": "The bioavailability of omega-3 fatty acids from flaxseed is influenced by the form of consumption, with ground seeds offering better absorption compared to whole seeds. Lignans require conversion by gut bacteria to enterolignans for optimal absorption."}

## Dosage & Preparation

No clinically studied dosage ranges were provided in the research. The available data contains only compositional analysis without information on therapeutic doses, standardization protocols, or clinical usage guidelines. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Flaxseed is generally well tolerated at doses up to 50g/day; higher doses may cause bloating, flatulence, and loose stools due to mucilage and fiber content. Raw flaxseed contains cyanogenic glycosides (linamarin, linustatin) that can release hydrogen cyanide, though typical dietary doses pose negligible risk and roasting reduces these compounds substantially. Flaxseed may potentiate anticoagulant and antiplatelet drugs (warfarin, aspirin, clopidogrel) due to ALA's inhibitory effect on platelet aggregation, and may reduce oral drug absorption when taken simultaneously due to its viscous fiber content. Pregnant women should use caution, as high-dose lignan intake has demonstrated weak estrogenic activity in animal studies, though moderate dietary consumption is considered safe.

## Scientific Research

The provided research contains only compositional and phytochemical analyses rather than clinical trials or meta-analyses. No human studies, RCTs, or clinical outcomes data were included in the research dossier. The available data focuses exclusively on chemical composition analysis and bioactive compound identification.

## Historical & Cultural Context

The research provided does not include information about traditional or historical use of linseed. No data on traditional medicine systems, historical applications, or cultural context was present in the available sources.

## Synergistic Combinations

Omega-3 supplements, vitamin E, plant-based proteins, fiber supplements, lignan-rich foods

## Frequently Asked Questions

### How much flaxseed should I take per day for cholesterol?

Clinical trials supporting LDL reduction typically used 30–40g of whole or ground flaxseed daily, consumed with meals. Ground flaxseed is significantly more bioavailable than whole seed, as the intact hull resists digestion and limits ALA and lignan absorption. Effects on LDL cholesterol typically become measurable after 4–8 weeks of consistent daily use.

### Is flaxseed a good source of omega-3 fatty acids?

Flaxseed is the richest known plant source of ALA (alpha-linolenic acid), providing approximately 22–24g of ALA per 100g of seed. However, human conversion of ALA to the more biologically active EPA and DHA is inefficient, typically under 10% for EPA and under 1% for DHA. Flaxseed omega-3s support anti-inflammatory pathways but should not be considered a substitute for marine-derived EPA/DHA in populations with high cardiovascular risk.

### Can flaxseed affect hormone levels in women?

Flaxseed's lignans, particularly SDG, are converted by gut bacteria to enterolactone and enterodiol, which act as weak phytoestrogens binding both ERα and ERβ. In postmenopausal women, several small RCTs (n=30–200) report modest improvements in hot flash frequency and vaginal dryness with 40g/day supplementation. In premenopausal women, high flaxseed intake has been associated with minor lengthening of the luteal phase, though clinical significance is unclear.

### What is the difference between whole flaxseed and ground flaxseed supplements?

Whole flaxseeds pass largely undigested through the gastrointestinal tract, limiting absorption of ALA and lignans by up to 50% compared to ground (milled) flaxseed. Cold-milled or ground flaxseed ruptures the seed coat, dramatically improving bioavailability of both fatty acids and SDG. Ground flaxseed is susceptible to oxidative rancidity due to its high polyunsaturated fat content and should be stored refrigerated in an airtight container and used within 30 days of milling.

### Does flaxseed interact with blood thinning medications?

Yes — flaxseed's ALA content inhibits platelet aggregation via reduced thromboxane A2 synthesis, and its lignans may have additive anticoagulant effects. Patients taking warfarin should be aware that flaxseed supplementation may prolong INR values, necessitating closer monitoring, particularly when doses exceed 15–20g/day. Concurrent use with antiplatelet drugs such as clopidogrel or aspirin also warrants medical supervision due to additive bleeding risk.

### Can flaxseed improve digestive health and support gut health?

Flaxseed contains both soluble and insoluble fiber, which can promote regular bowel movements and support a healthy gut microbiome by serving as a prebiotic for beneficial bacteria. The lignans in flaxseed, particularly SDG, may also have prebiotic properties that enhance microbial diversity. However, consuming adequate water with flaxseed is important to avoid digestive discomfort, and gradual introduction is recommended for those with sensitive digestive systems.

### Is flaxseed safe for people with certain medical conditions like diabetes or thyroid disease?

Flaxseed is generally considered safe for people with diabetes due to its low glycemic index and high fiber content, which can help stabilize blood sugar levels. However, individuals with thyroid conditions should consume flaxseed in moderation and maintain consistent intake, as some compounds in flaxseed may interfere with thyroid hormone absorption; consulting with a healthcare provider is recommended. Additionally, those with bowel obstruction or acute gastrointestinal issues should avoid flaxseed supplementation.

### Does flaxseed contain complete protein, and how does it compare to other plant-based protein sources?

Flaxseed contains all nine essential amino acids, making it a relatively complete plant-based protein source with approximately 20g of protein per 100g, though it is lower in lysine compared to legumes. While flaxseed provides quality amino acids including notable amounts of leucine and lysine, it is typically used as a complementary protein rather than a primary protein source due to its lower total protein content compared to seeds like hemp or pumpkin. Combining flaxseed with other plant proteins or whole grains can improve overall amino acid profile.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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