Are polyunsaturated fatty acids good for you?

Are oils rich in polyunsaturated fatty acids bad for you?

The data's in and an overwhelming number of peer reviewed scientific articles agree:  Your body needs polyunsaturated fatty acids. 

Certain polyunsaturated fatty acids are absolutely essential to your health because your body can't make them. 

What two classes of polyunsaturated fatty acids (PUFAs) are relevant to your health?  Omega-3’s and omega-6’s.

So, why do omega-6’s get such a bad rep right now?

Because there’s an optimal ratio between omega-3 and omega-6 fatty acids that your body needs.  The two essential fatty acids are the omega-3 fatty acid, alpha-linolenic acid (ALA) and the omega-6 fatty acid, linoleic acid (LA).

These two essential fatty acids are required by your body to make longer chain omega-3’s and omega-6’s.

The omega-3 pathway involves creation of the anti-inflammatory fatty acid, eicosapentanoic acid (EPA) from ALA.  And, ultimately EPA is converted into DHA (docosahexanoic acid) in the body.

And, the omega-6 pathway involves creation of the pro-inflammatory fatty acid, arachidonic acid, from LA.  The story on arachidonic acid is deeper than this and in fact further metabolism of arachidonic acid may be down either pro-inflammatory or anti-inflammatory pathways.

And, let's be real, pro-inflammatory is a scary word.  We’ll get to that part of the conversation in a sec, first, let’s wrap up the rest of the story on this conversion process.

The same enzymes are required for converting both omega-3's and omega-6's into other molecules within your body, and enzymes are not multi-taskers, so when an enzyme’s busy converting one fatty acid, it can’t be busy converting a second fatty acid.

And, this is why the ratio of omega-3 to omega-6 fatty acids is so important in your diet. 

Most experts recommend a 4 to 1 ratio of omega-6 to omega-3, and the risk of certain cancers improves by moving that ratio down to a 2:1 ratio of omega-6:omega-3.

What's the omega-6 to omega-3 ratio in the Standard American Diet? 

Closer to a 16 to 1 ratio of omega-6 to omega-3, so yeah, we’re getting our omega-6’s.  Putting this in perspective, for every 1 teaspoon of omega-3 you eat, you’re consuming 5 Tablespoons (+ 1 tsp) of omega-6’s.  The recommendation is at max 4 teaspoons omega-6 (or 1 Tablespoon + 1 teaspoon) to every 1 teaspoon of omega-3’s you eat.

If omega-6’s are involved in pro-inflammatory processes, why’s it okay to eat more of them?  Because those enzymes have a higher affinity for omega-3’s than they do omega-6’s.

Your age, your health, your gender, and your genes also impact how well your body converts those essential fatty acids into the longer fatty acids throughout the conversion pathway.  Healthy young men convert about 8% of dietary ALA to EPA and only about 0% to 4% ALA to DHA (hence the big push for including sources of EPA and DHA in your diet).  Young healthy women convert about 21% of their dietary ALA into EPA and about 9% of their dietary ALA into DHA.

The same kind of loss of conversion happens along the omega-6 pathway, and this is why gamma-linolenic acid (GLA), which is the first step of the conversion pathway after linoleic acid, is considered conditionally essential in the arachidonic acid pathway.

Why pro-inflammatory pathways are necessary for your health

Both the omega-6 EFA linoleic acid and also arachidonic acid have been demonstrated to have an anti-cancer protective effect in several research studies.

We often think of pro-inflammatory as being bad or undesirable, but the body is a highly intelligent creation, and there's necessity in balance.  In fact, health is found in balance.  It's necessary for a degree of inflammation in order to respond appropriately when there's a crisis... for example:

  • when you've cut yourself or
  • when a bacteria or virus invades or
  • when cells naturally die and need to be removed from your body or
  • when a cell goes rogue... the pro-inflammatory process is vital to catching rogue cells before they have a chance to proliferate into cancer

Arachidonic acid plays a role in recovery following exercise and because the body is able to shunt it down additional pro- or anti-inflammatory metabolic pathways, some studies have even found that arachidonic acid reduces systemic inflammation within the body.

This points to how your body uses arachidonic acid as being the critical piece of the pro- or anti-inflammatory conversation.

And, to expand this piece of the conversation beyond arachidonic acid, it turns out the same is true of other essential fatty acids and the entire group of PUFAs (whether or not they're the two EFA PUFAs) in general.

Both the omega-6 EFA linoleic acid and also arachidonic acid have been demonstrated to have an anti-cancer protective effect in several research studies.

We often think of pro-inflammatory as being bad or undesirable, but the body is a highly intelligent creation, and there's necessity in balance.  In fact, health is found in balance.  It's necessary for a degree of inflammation in order to respond appropriately when there's a crisis... for example:

  • when you've cut yourself or
  • when a bacteria or virus invades or
  • when cells naturally die and need to be removed from your body or
  • when a cell goes rogue... the pro-inflammatory process is vital to catching rogue cells before they have a chance to proliferate into cancer

Arachidonic acid plays a role in recovery following exercise and because the body is able to shunt it down either pro- or anti-inflammatory metabolic pathways, some studies have even found that arachidonic acid reduces systemic inflammation within the body.

This points to how your body uses arachidonic acid as being the critical piece of the pro- or anti-inflammatory conversation.

And, to expand this piece of the conversation beyond arachidonic acid, it turns out the same is true of other PUFAs within your body.  It’s been demonstrated with prancreatic beta cells that when a stimulus (stimulus is synonymous with stressor) is present, in the case of pancreatic beta cells, this stressor is glucose, then cellular membranes give up some of their PUFA content.  The PUFAs liberated from the cellular membrane are now inside the cell, and here they undergo lipid peroxidation to form a compound known as 4-hydroxynonenal (4-HNE), which triggers the release of insulin.  4-HNE is a reactive aldehyde, and this sounds really bad at face value.  Why would the body do that?

It's because when we’re talking about health, balance is key. 

At low levels, 4-HNE is beneficial to cells and promotes cellular differentiation, builds antioxidant defense mechanisms, and encourages growth and vitality.  However, at higher concentrations, 4-HNE turns on toxic pathways that result in cell death.  And, here’s the thing, sometimes, cell death is crucial.  For example, when DNA is badly damaged or the cell itself is badly damaged, cell death is necessary for health, and this is an overarching theme in the body.

Your body has all of these intricate pathways that are influenced by a whole myriad of different compounds, and when cellular intelligence is functioning optimally, sacrifice of individual cells for the good of the whole being (that’s you), is often made.

The fact that sugar prompts formation of 4-HNE is just one example of how important everything is.  When we're talking health, everything matters.

And, yet, in the current landscape, PUFAs are being villainized as the cause of a whole host of health problems, and this simply isn’t true.  You don't exist in a vacuum and while you (like me) are likely eating too much omega-6 compared with omega-3, changing that ratio alone won't solve a health crisis.  And, PUFAs (and seed oils) alone aren't something to be feared, rather they're to be enjoyed... just in moderation.

References

Ferreri C, Masi A, Sansone A, Giacometti G, Larocca AV, Menounou G, Scanferlato R, Tortorella S, Rota D, Conti M, Deplano S, Louka M, Maranini AR, Salati A, Sunda V, Chatgilialoglu C. Fatty Acids in Membranes as Homeostatic, Metabolic and Nutritional Biomarkers: Recent Advancements in Analytics and Diagnostics. Diagnostics (Basel). 2016 Dec 22;7(1):1. doi: 10.3390/diagnostics7010001. PMID: 28025506; PMCID: PMC5373010.
 
Vegan sources of omega-3 and omega-6 fatty acids (Table near bottom of article + more links to journal articles)

References (copied from last two sources listed above)

Reference 1.  Phospholipids.  https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Book%3A_Introductory_Chemistry_(CK-12)/26%3A_Biochemistry/26.9%3A_Phospholipids

Reference 2.  https://images.app.goo.gl/RrZDJMvayctU98ka6

Reference 3.  Fluid mosaic model: cell membranes article. https://images.app.goo.gl/c5gYTcYhhy8oboKu8

Reference 4.  https://chem.libretexts.org/Courses/University_of_Kentucky/UK%3A_CHE_103_-_Chemistry_for_Allied_Health_(Soult)/Chapters/Chapter_14%3A_Biological_Molecules/14.2%3A_Lipids_and_Triglycerides

Reference 5.  https://www.tuscany-diet.net/tag/polyunsaturated-fatty-acids/

Reference 6 https://academic.oup.com/jn/article/128/2/427S/4724041

Reference 7. Omega 3 fatty acids on child growth, visual acuity and neurodevelopment.  Cristina Campoy, Mª¯ Victoria Escolano-Margarit, Tania Anjos1, Hania Szajewska2 and Ricardo Uauy. British Journal of Nutrition (2012), 107, S85–S106 doi:10.1017/S0007114512001493

Reference 8.  Essential Fatty Acid Deficiency in Human Adults During Total Parenteral Nutrition.  MC Riella, JW Broviac, M Wells, and BH Scribner. Downloaded from http://annals.org / by Penn State University Hershey User on 09/19/2016.

Reference 9.  Neurobiology of Disease.  A Diet Enriched with the Omega-3 Fatty Acid Docosahexaenoic Acid Reduces Amyloid Burden in an Aged Alzheimer Mouse Model.  Giselle P. Lim, Frédéric Calon, Takashi Morihara, Fusheng Yang, Bruce Teter, Oliver Ubeda, Norman Salem Jr, Sally A. Frautschy and Greg M. Cole

Reference 10.  Docosahexaenoic acid and human brain development: Evidence that a dietary supply is needed for optimal development.  Journal of Human EvolutionVolume 77, December 2014, Pages 99-106.  J. ThomasBrenna and Susan E.Carlsonhttps://www.sciencedirect.com/science/article/abs/pii/S0047248414000839

Reference 11.  Koletzko B: Human Milk Lipids. Ann Nutr Metab 2016;69(suppl 2):27-40. doi: 10.1159/000452819.

Reference 12.  J Thomas Brenna, Behzad Varamini, Robert G Jensen, Deborah A Diersen-Schade, Julia A Boettcher, Linda M Arterburn, Docosahexaenoic and arachidonic acid concentrations in human breast milk worldwide, The American Journal of Clinical Nutrition, Volume 85, Issue 6, June 2007, Pages 1457–1464, https://doi.org/10.1093/ajcn/85.6.1457

Reference 13.  https://www.dietobio.com/dossiers/en/nuts/fats.html

Reference 14.  Essential Fatty Acids in Vegetarian Nutrition.  https://www.scienzavegetariana.it/medici/essentialfat.html

Reference 15.  Plant Sources of Omega-3 Fatty Acids.  https://www.healthline.com/nutrition/7-plant-sources-of-omega-3s#section2

Reference 16.  Dietary Sources of DHA & EPA.  https://www.medicalnewstoday.com/articles/323144.php#fish-sources-of-omega-3.

Reference 17.  The importance of the ratio of omega-6/omega-3 essential fatty acids. https://www.ncbi.nlm.nih.gov/pubmed/12442909

Reference 18.  February 2010.  Vegetarian’s Challenge — Optimizing Essential Fatty Acid Status.  By Brenda Davis, RD.  Today’s Dietitian.  Vol. 12 No. 2 P. 22. https://www.todaysdietitian.com/newarchives/020810p22.shtml

Additional References

https://medicaldetectivemd.com/2019/03/01/when-is-the-last-time-you-checked-your-oil-fish-oil/

Journal of Neuroscience 23 March 2005, 25 (12) 3032-3040; DOI: https://doi.org/10.1523/JNEUROSCI.4225-04.2005

https://www.jneurosci.org/content/25/12/3032.short

Are Neurodegenerative Disorder and Psychotic Manifestations Avoidable Brain Dysfunctions with Adequate Dietary Omega-3?  Letten F. SaugstadFirst Published July 1, 2006 Research Article Find in PubMedhttps://doi.org/10.1177/026010600601800302

https://journals.sagepub.com/doi/abs/10.1177/026010600601800302

Omega-3 for your eyes. https://www.health.harvard.edu/heart-health/omega-3-for-your-eyes

Fatty Acid Composition of Human Brain Phospholipids during Normal Development.  https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1471-4159.1998.71062528.x

Journal of Lipid Research.  Lipid composition of the normal human brain: gray matter, white matter, and myelin*John S. O'Brien and E. Lois Sampson.  October 1965.  Volume 6, pages 537-544.

Fatty Acids and the Aging Brain.  Alyssa Bianca Velasco, Zaldy S. Tan, in Omega-3 Fatty Acids in Brain and Neurological Health, 2014

Fatty Acid Composition of the Brain.  https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/lipid-composition

https://www.sciencedirect.com/science/article/abs/pii/S0952327809001987

Reference 1.  https://www.tuscany-diet.net/tag/polyunsaturated-fatty-acids/

Reference 2.  Essential Fatty Acidshttps://lpi.oregonstate.edu/mic/other-nutrients/essential-fatty-acids#deficiency

Reference 3.  William W. Christie.  Prostanoids: Prostaglandins, Prostacyclins
and Thromboxanes.  https://www.lipidhome.co.uk/lipids/fa-eic/eicprost/index.htm

Reference 4.  Zreik, T, Behrman, H, Glob. libr. women's med., The Prostaglandins: Basic Chemistry and Action (ISSN: 1756-2228) 2008; DOI 10.3843/GLOWM.10313 Under review - Update due 2020.  https://www.glowm.com/section_view/heading/The%20Prostaglandins:%20Basic%20Chemistry%20and%20Action/item/312

Reference 5.  Hruza LL1Pentland APJ Invest Dermatol. 1993 Jan;100(1):35S-41S.  Mechanisms of UV-induced inflammation.  https://www.ncbi.nlm.nih.gov/pubmed/8423392

Reference 6.  https://www.researchgate.net/figure/2-Oxygenation-pathways-of-arachidonic-acid-AA-and-docosahexaenoic-acid-DHA-in-CNS_fig1_273133662

Reference 7.  https://images.app.goo.gl/RrZDJMvayctU98ka6

Reference 8. https://academic.oup.com/jn/article/128/2/427S/4724041

Reference 9.  Koletzko B: Human Milk Lipids. Ann Nutr Metab 2016;69(suppl 2):27-40. doi: 10.1159/000452819.

Reference 10.  https://www.dietobio.com/dossiers/en/nuts/fats.html

Reference 11.  The importance of the ratio of omega-6/omega-3 essential fatty acids. https://www.ncbi.nlm.nih.gov/pubmed/12442909

Reference 12.  February 2010.  Vegetarian’s Challenge — Optimizing Essential Fatty Acid Status.  By Brenda Davis, RD.  Today’s Dietitian.  Vol. 12 No. 2 P. 22

Additional References

Journal of Neuroscience 23 March 2005, 25 (12) 3032-3040; DOI: https://doi.org/10.1523/JNEUROSCI.4225-04.2005.

https://www.jneurosci.org/content/25/12/3032.short

https://www.todaysdietitian.com/newarchives/020810p22.shtml

https://medicaldetectivemd.com/2019/03/01/when-is-the-last-time-you-checked-your-oil-fish-oil/

Are Neurodegenerative Disorder and Psychotic Manifestations Avoidable Brain Dysfunctions with Adequate Dietary Omega-3?  Letten F. SaugstadFirst Published July 1, 2006 Research Article Find in PubMedhttps://doi.org/10.1177/026010600601800302

https://journals.sagepub.com/doi/abs/10.1177/026010600601800302

Omega-3 for your eyes. https://www.health.harvard.edu/heart-health/omega-3-for-your-eyes

Fatty Acid Composition of Human Brain Phospholipids during Normal Development.  https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1471-4159.1998.71062528.x

Journal of Lipid Research.  Lipid composition of the normal human brain: gray matter, white matter, and myelin*John S. O'Brien and E. Lois Sampson.  October 1965.  Volume 6, pages 537-544.

Fatty Acids and the Aging Brain.  Alyssa Bianca Velasco, Zaldy S. Tan, in Omega-3 Fatty Acids in Brain and Neurological Health, 2014

Fatty Acid Composition of the Brain.  https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/lipid-composition

https://www.sciencedirect.com/science/article/abs/pii/S0952327809001987

Brandy Searcy founder Rain Organica

About the Author

Brandy's a formulation scientist and self-proclaimed health geek who loves hiking, gardening, bird-watching, and body boarding. 

Her struggle with acne during her teens and 20s led to a holistic and healthy approach to skincare, embracing skin as an organ to be loved and cared for rather than a canvas to wage war on. 

Since 2008, she's been developing all-in-one products for a simple routine at home, & Rain Organica started when her backpacking friends asked for a portable skincare routine to keep their skin healthy & happy on and off the trails.

You can try Rain Organica for yourself with The Essentials Kit, a complete skincare routine in just 3 steps.

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