What is it used for?
Source of essential fatty acids for the maintenance of good health [Source note 2].
Source of omega-3 fatty acids for the maintenance of good health [Source note 3].
Source of alpha-linolenic acid (ALA) for the maintenance of good health [Source note 4].
Source of omega-6 fatty acids for the maintenance of good health [Source note 5].
Source of linoleic acid (LA) for the maintenance of good health [Source note 6].
(Used in Herbal Medicine as a) bulk-forming laxative [Source note 7].
(Used in Herbal Medicine to) promote(s) bowel movement (by increasing bulk volume and water content) [Source note 8].
(Used in Herbal Medicine to) provide(s) gentle relief of constipation and/or irregularity [Source note 9].
(Used in Herbal Medicine to) help(s) reduce blood lipid levels in adults [Source note 10].
Source of antioxidants/Provides antioxidants [Source note 11].
Source of antioxidants/Provides antioxidants that help fight/protect (cell) against/reduce (the oxidative effect of/the oxidative damage caused by/cell damage caused by) free radicals [Source note 12].
Note: The above uses can be combined on the product label if from the same non-traditional system of medicine (e.g. Used in Herbal Medicine as a bulk-forming laxative for gentle relief of constipation and/or irregularity).
Who does this guide cover?
As specified below.
How is it taken?
Oral
Which forms are covered?
this reference excludes foods or food-like dosage forms as indicated in the Compendium of references Guidance Document.
Quantities
Method of preparation: Powdered¹
| Uses or Purposes | Subpopulations¹,² | Subpopulations¹,² | Dried seed (g)/day / Min. | Dried seed (g)/day / Max. | Dried seed (g)/single dose / Max. single dose |
|---|---|---|---|---|---|
| Source of essential fatty acids, omega-3 fatty acids, and/or ALA | Children | 6-11 years | 0.18 | 15 | 7.5 |
| Source of essential fatty acids, omega-3 fatty acids, and/or ALA | Adolescents | 12-17 years | 0.36 | 45 | 22.5 |
| Source of essential fatty acids, omega-3 fatty acids, and/or ALA | Adults | 18 years and older | 0.36 | 45 | 22.5 |
| Source of omega-6 fatty acids and/or LA | Children | 6-11 years | 7 | 15 | 7.5 |
| Source of omega-6 fatty acids and/or LA | Adolescents | 12-17 years | 14 | 45 | 22.5 |
| Source of omega-6 fatty acids and/or LA | Adults | 18 years and older | 14 | 45 | 22.5 |
| Provides antioxidants | Children | 6-11 years | >0 | 15 | 7.5 |
| Provides antioxidants | Adolescents | 12-17 years | >0 | 45 | 22.5 |
| Provides antioxidants | Adults | 18 years and older | >0 | 45 | 22.5 |
| Reduces blood lipid levels | Adults | 18 years and older | 30 | 45 | 22.5 |
¹Children and adolescent doses were calculated as a proportion of the adult dose [Source note 13]. The use of Flaxseed in children and adolescents is supported by the following references: ESCOP 2003; Bove 2001; Boon 2000; Schilcher 1997. ²Adult dose supported by the following references: EMA 2015; Patade et al. 2008; IOM 2006; ESCOP 2003; Lucas et al. 2002; Jenkins et al. 1999; Cunnane et al. 1993.
Methods of preparation: Dry, Powdered¹
| Uses or Purposes | Subpopulations¹,² | Subpopulations¹,² | Dried seed (g)/day / Min. | Dried seed (g)/day / Max. | Dried seed (g)/single dose / Max. single dose |
|---|---|---|---|---|---|
| Laxative | Children | 6-11 years | 4.5 | 15 | 7.5 |
| Laxative | Adolescents | 12-17 years | 10 | 45 | 22.5 |
| Laxative | Adults | 18 years and older | 10 | 45 | 22.5 |
¹Children and adolescent doses were calculated as a proportion of the adult dose [Source note 14]. The use of Flaxseed in children and adolescents is supported by the following references: ESCOP 2003; Bove 2001; Boon 2000; Schilcher 1997. ²Adult dose supported by the following references: EMA 2015; Patade et al. 2008; IOM 2006; ESCOP 2003; Lucas et al. 2002; Jenkins et al. 1999; Cunnane et al. 1993.
¹ Note: The method of preparation 'powdered' is defined as a dried and ground preparation (= unextracted).
Optional potency:
All products
20-30 % ALA [Source note 15]
and/or
5-7 % LA [Source note 16].
How is it used?
Products providing 5 g or more of flaxseed per day
For each dose, drink at least 250 ml of liquid [Source note 17].
Mix well with liquid and drink immediately.
Maintain adequate fluid intake [Source note 18].
Take a few hours before or after taking other medications or health products [Source note 19].
Laxative; Promotion of bowel movement; Constipation relief
Effects observed 12-24 hours after first dose, and may take 2-3 days [Source note 20].
Optional
Take during the day (not immediately prior to bedtime) [Source note 21].
Optional (for products with a dosage range)
Minimum daily dose may be increased, up to the maximum daily dose, until desired effect is obtained.
How long is it used?
The reference does not require an additional label statement in this section. This does not establish an absence of risk.
Warnings and precautions
Products providing 5 g or more of flaxseed per day
Ask a healthcare professional immediately if you experience chest pain, vomiting, or difficulty swallowing or breathing after taking this product [Source note 22].
Ask a healthcare professional before use if you have diabetes or a lazy bowel [Source note 23].
Laxative; Promotion of bowel movement; Constipation
Ask a healthcare professional if symptoms worsen or if laxative effect does not occur within 7 days [Source note 24].
When should it be avoided?
Products providing 5 g or more of flaxseed per day
Do not use if you have difficulty swallowing [Source note 25].
Do not use if you have fever or any undiagnosed gastrointestinal trouble [Source note 26].
Possible side effects
All products
Stop use if hypersensitivity/allergy occurs [Source note 27].
Storage
Must be established in accordance with the requirements described in the applicable product regulations.
Preparation details
Ingredient identity, preparation requirements, and other details that define the scope of this guide.
Ingredients and preparations
| Proper name(s) | Common name(s) | Source information / Source material(s) | Source information / Part(s) | Source information / Preparation(s) |
|---|---|---|---|---|
| Linum usitatissimum |
| Linum usitatissimum | Seed | Dry |
References: Proper name: USDA 2024; Common names: Sweetman 2007; Gardner and McGuffin 2013; Source information: Blumenthal et al. 2000.
Other ingredients
Must be chosen from the current source ingredient database and must meet the limitations outlined in the database.
Preparation and quality requirements
The finished product specifications must be established in accordance with the requirements described in the source authority source’s product quality guidance.
The active ingredient must comply with the requirements outlined in the source ingredient database.
Guide change history
Updates to this SupplementSafety.org guide.
Minor updates
Updated guide wording, organization, and source presentation. Added our editorial change history.
Initial release
Initial SupplementSafety.org guide prepared from source reference material.
Validation: Not yet completed. Editorial updates do not constitute clinical validation.
Sources
Source information
This guide organizes source material about uses, preparations, amounts, and precautions. Read the conditions alongside each statement; the information may apply only to particular preparations or populations.
The source document includes supporting references. We have not independently summarized or assessed every cited study for this guide.
- Source document version
- July 26, 2024
- Source captured
- Aug 15, 2026
- Editorial work
- Editorial preparation. Independent clinical review has not been recorded for this guide.
Full citations are available through the link above. Verification is required to open them; reading this guide does not require verification.
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