Stealth Sources of Omega 6 Linoleic Acid
Sources of Omega 6 Linoleic Acid
although this basenote is publicly-visible,
some links and responses may be UIC members-only,
or to premium external sources.
This may be just precautionary fine tuning, or might turn out to
be important. In either case, if you’ve decided to take a hard
look at your Omega 6 linoleic acid intake (ω6LA
hereafter, aka 18:2 ω6 cis,cis-9,12
or n-6), this article might be of some use.
The Undoctored/Wheat Belly program cautions about ω6LA,
most recently in
Clarity on omega-6 fatty acids
(on WB Blog,
“You don’t want omega-6
overload, but you also don’t want omega-6 deficiency.
The ideal omega-6:omega-3 index (i.e., the ratio of omega6:omega-3
in cells of the body, such as red blood cells) is 2:1 or less
and closer to the historical level of 1:1 that prevailed prior
to the agricultural age. …”
Omega 6:3 ratio (and Omega 3 Index) is probably pointless
during weight loss, as the weight being lost is mobilized stored fat,
and fat that represents the prior diet, likely high in ω6LA.
But the program guidance is clear:
minimize or eliminate added
You’re going to get ample from
nuts, recommended seeds, fish, meats, eggs and some dairy.
The production of industrially refined oils from non-food seeds
appears to have started with cottonseed oil in 1857, but was
explosively extended to other grains and legumes over
the past half century. These sources are very high in ω6LA.
of human fat reflects this, as
do waistlines, but the obesity problem has more factors than
just so-called vegetable oil.
If you don’t know how much ω6LA you are
consuming, you might want to find out. There’s some chance that it’s too
much. If following the Undoctored or Wheat Belly program hasn’t
delivered all of the health benefits you expected, and everything else
has been ruled out, stealth ω6LA
may be playing a role, at the very least preventing you from
attaining your desired
Those familiar with the concerns about
ω6LA, and the usual sources of it, can just skip
down to Stealth Sources of Excess LA.
The potential hazards of excess ω6LA are for the most part
not recent developments. A 1963 paper discusses it, and that may
not be the oldest:
Lipid Fatty Acids During Fasting
Am J Clin Nutr
A team of investigative scientists has also turned up that two
landmark trials used to prop up the early cholesterol hypothesis,
(I’m being charitable) to
publish their data, hid
not just that lower cholesterol correlated to reduced lifespan,
but that doing it by replacing saturated fats with polyunsaturated
fats high in ω6LA was probably a factor.
Various fatty acids, including the poly-unsaturated (PUFA)
ω6LA and ω3s are generally
considered “essential”, or an
It is true that humans cannot
synthesize the EFAs. But if we are on an LCHF diet, we probably do not
need to deliberately attend to getting ample ω6LA.
Specifically assuming that more is better would be a serious
mistake (and deliberately consuming oils with excess ω6LA
has been a key part of government and consensus
medicine “low fat” policy over the last several decades).
It is thought that ancestral human intake of ω6:ω3
was in a ratio of near 1:1. The proportion of ω6 doubtless began
rising with agriculture (grain seeds are high in ω6),
ramped up during the 20th century, and accelerated in the last
several decades (due both to dietary policy and due
to refining it from subsidized crops).
are now at ω6:ω3 ratios as high as 18:1.
The trend line for the
production and consumption of industrial seed oils (the majority
of the so-called vegetable oils) is a perfect correlate to
trends in many chronic non-infectious ailments — this may be
no coincidence. Return to ToC
The Potential ω6LA
I personally consider low-fat mania to be the #3 problem in modern
diet, behind #2 (added sugars) and #1 (grains, wheat in particular).
The low-fat mania problem itself breaks down into several parts:
• low overall fat consumption,
• groundless saturated fat phobia,
• excess PUFA intake
(ω6LA in particular), and
• some residual trans-fat exposure (now in decline, fortunately).
An Undoctored forum user has
a useful page about PUFAs, with links
to various papers on the conjectured etiologies.
It’s also been discussed in this forum, most recently at:
much 18:2 ω-6 linoleic acid do you really want to eat?
There are other pundits tallying the potential issues,
as Tucker Goodrich.
Adverse effects of excess ω6LA
may include, but are not limited to:
- competes with ω3 where you need it
- cancer correlations (mitochondrial disruptor?)
- strongly suspected in CVD
be inherently obesogenic (distorts insulin resistance)
- strongly suspected in
- suspected in dysbiosis due to anti-microbial properties.
These oils are actually used as pesticides afield.
- thyroid/liver effects: above a specific ω6LA titer,
the liver, in response to thyroxine,
decreases beneficial fatty acid synthesis and
inhibits glycogen depletion (demonstrated in rodents)
What are the direct effects on important lab tests, such
as hsCRP, HDL, LDL-P and Lp(a)?
Finding unambiguous data seems unlikely, primarily due to
trials confounded by diets uncontrolled
for carbohydrate consumption, or not including an arm on
a diet anything like what is advocated here. N=1 trials
may be the near term alternative (that would be you).
That Transtronics page includes a
list of PUFA oils, and their ω6LA
content. I consider 15% to be a rough upper limit for an oil
suitable for routine use, unless it has a favorable
ω6:ω3 ratio, or other redeeming factor(s). Return to ToC
Obvious Sources of ω6LA
The following oils have no place in an
Undoctored or Wheat Belly pantry (as oils):
Canola (and Rapeseed), Corn, Cottonseed, Grape Seed,
Hemp, Linseed, Peanut, Pistachio, Poppy Seed,
Pumpkin Seed, Safflower, Rice Bran, Soybean,
Sunflower, Wheat Germ.
This is just on the
basis of ω6LA content. Some of these oils present
additional content issues as well.
Many of the above have further problems due to how they
are processed. See the unintentionally notorious How
It’s Made video on canola for an
example. High temperatures cause oxidation. Chemical
solvents can end up as residues. Deodorants may be added,
along with BHA and BHT.
Oils that might be OK for light or occasional use are:
Some of the above are fine as whole seeds, whole nuts or flours,
including almond, hemp, pistachios, pumpkin seeds, sesame seeds,
sunflower seeds, walnuts and peanuts (limited).
Recommended oils, that meet or are below my 15%LA cut-off are:
(ONLY if credible),
Coconut, Flax, Ghee,
Olive (ONLY if credible),
Palm (*). Return to ToC
Plain Sources of ω6LA
Once attuned to minimizing ω6LA, the following
sources are relatively easy to identify and avoid,
usually by examining both the Nutrition Facts panel
and the Ingredients list:
- The majority of processed ready-to-eat foods contain
oils high in ω6LA, not to mention grains,
added sugars, preservatives, emulsifiers,
food coloring, flavorants and other junk.
- The majority of condiments contain oils high in ω6LA,
including spreads (margarine), salad dressings,
mayonnaise, and non-dairy
mimic products. Low-fat versions of these may have
less or no LA, but may be expected
to be high glycemic instead.
- Restaurant meals must be presumed to have been prepared
in or with adverse ω6LA oils, unless specifically disclaimed
(and price does not protect you on this).
- Cooking sauces and fillings require close examination:
tartar, hollandaise, etc. are likely to be soy slimes.
- Supplements in capsule form often contain soybean or
other adverse oil.
Nutrition Facts and Ingredients
disclosures never call out ω6LA specifically,
by the way. Even at Nutritiondata.self.com,
their detailed Fats and Fatty Acid breakdowns for
foods and products may show
the 18:2 content under Polyunsaturated Fat
but fail to tell you the name of that (or any of the other
fatty acids). So expect little help on avoidance in
processed food-like substances. Return to ToC
Stealth Sources of Excess ω6LA
If you are using a food oil for its health benefits,
don’t buy something that is providing health
hazards instead —
because it isn’t what the label claims.
Avocado and Olive oils are already known to be at
extreme risk of not being what they claim. In its 2021 update to its EVOO testing,
ConsumerLabs (CL) passed only 3 of the oils they tested.
See the Olive
Oil Tips below for how to navigate this minefield.
The avocado oil situation is even more dire. As of the latest update
to the present article, CL had yet to publish a test, but they did
turn up this very disturbing 2020 paper:
MDPI: Analysis and Authentication of
Avocado Oil Using High Resolution NMR Spectroscopy
Three of the oils tested tested as almost certainly
being entirely mis-labeled soybean oil.
When cheap industrial grain and legume oils can be tarted up with
flavorants, colorants and deodorants, and sold as much higher priced
trendy-oils, they will be. This means that hazelnut, macadamia and palm
oils are likely also at high risk of being counterfeit. Part of the
problem here is not just the financial incentives, but that national
nutrition nannies think all “vegetable“ oils are just peachy
for health, so what’s the big deal?
The already-alert ω6LA detective also needs to be on the
lookout for LA arriving unannounced via:
- This olive oil problem applies to any processed food
product that purports to contain olive oil. You may
safely assume that any major brand product listing
olive oil as an ingredient is at some risk of not
containing what they want you to think it does.
The more prominent the mention of OO, the more likely
they think they are pandering to a fad that doesn’t
matter, and thus doesn’t merit any real attention to quality control.
- Almost any oil, used for any purpose, in a restaurant
meal, is going to be a cheap industrial seed oil.
Go for baked or grilled dishes, not fried. Ask
for sauces and dressings on the side. As infrequently as
I eat at Chipotle, their use of rice bran oil isn’t that
great a hazard.
- What passes for “butter” in restaurants, both
on the table and in the kitchen, is often a
butter/PUFA blend, and may be expected to be CAFO
butter as well.
meats have a more
adverse ω6:ω3 ratio. Curiously,
this is not due to higher ω6, but because the ω3
is driven to nil. However, the absolute levels of omegas
in muscle meats are so low that this is not a major issue.
So avoid CAFO meats, and seek grass-fed pastured
(pasture-finished) organic due to second-hand growth
hormones, antibiotics, pesticide residues, etc.
- Getting back to using lard or tallow? Make sure it’s grass-fed. In
one test, CAFO lard was found to be over 16:1 ω6:3,
vs. 1.4:1 for grass-fed. The grass-fed was also lower in natural
trans fats. Your bacon needs to be pastured as well.
That will cover most situations. If it doesn’t:
Return to ToC
- Don’t go nuts on the nuts. Excessive consumption of even almonds
can present an elevated ω6LA exposure.
- If you are eating fish to get ω3 DHA&EPA, make
sure you actually get it.
Fish, unless a species that cannot be farmed, or credibly
claimed to be wild caught, must be presumed to be farmed,
and fed the same sort of ω6LA-laden chow that
terrestrial critters suffer, which ends up in the fish fat,
increases the ω6:ω3 ratio. Cross tilapia off your
- If you won’t eat CAFO bacon or steak, don’t drink CAFO milk/cream,
don’t use CAFO butter, and maybe not eat CAFO cheese.
Grain-fed cows produce milk with a much higher
unless the cows are getting ω3 supplements, which may be presumed
to be ALA, and which probably
does nothing to reduce the ω6 content.
However, ω6LA content in the milk may be a secondary
problem compared to the beta casein A1 issue. rBST frets are further
down the list. Again, seek organic, grass-fed, pastured, A2
(goats and sheep are A2).
- If you’re really determined to drive down ω6LA, another
common source is chickens, and
their eggs. ω3 is not the only nutrient
depressed in CAFO eggs. Seek pastured
organic eggs. Although chicken and eggs, even
pastured organic, have an unfavorable ω6:ω3
ratio, the fat content is also low, so the ω6LA
absolute content is low.
ω6LA Reduction Checklist
Omega 3 Index and Omega 6:3 ratio are two tests
suggested when there are concerns on this topic. These provide
a baseline for assessing the results of any dietary
adjustment. If you are presently loosing weight, these
tests might be misleading, as they may be biased
toward the profile of fat stores, and not current diet.
Even when weight stabilizes, it may take some time for the
Omega tests to reflect eventual status. What you are eating is
going in. What’s coming out may have been eaten long ago.
The half-life of
adipose fat has been conjectured to be as high as
600 days (but
this is disputed).
To re-cap, to reduce your exposure to ω6LA, take the
Return to ToC
- Get ample Omega 3
DHA & EPA. This is normally going to mean
supplementing. ω6:3 ratio matters.
- Stop buying, and discard all of the "no place in your pantry"
oils listed earlier.
- Stop consuming any processed foods that contain
- Major offenders in processed foods are salad
dressings (almost all of them), mayonnaises (almost
all of them) sauces, dips, etc.
- Check your capsule supplements for the above oils,
and switch to other formulations on re-order.
- Stop consuming deep-fried restaurant dishes, which
may be presumed to have been cooked in, and loaded
with, one of the above oils, in a well-oxidized
if not rancid form. Think twice about sauteed or
- Do not use restaurant butter, unless packaged with
credible claims (unlikely).
- Do a background check on your seed oils. This is
likely to result in discarding it, and switching
to something with a credible provenance.
- Seek credibly wild-caught fish, and not packed
in oil, as any claim of even olive oil cannot
be relied on.
- Minimize consumption of peanuts, and especially
most peanut butters (which have added ω6LA
- If you have any of the following oils (as refined oils),
mark them "Use Sparingly":
Almond, Sesame, Walnut
- Seek pasture-raised pasture-finished organic land animal
products, including dairy and eggs.
If you don’t know, you must assume the source is
which may be expected to be high in ω6LA,
low in ω3, and bear second-hand antibiotics,
second-hand hormones, plus pesticide uptake.
- If Omega blood tests remain unfavorable, consider
moderating pork intake, and…
- On chicken, favor the white meat, which is very
low in ω6LA.
Olive Oil Tips
Here are the criteria I’d apply (and with a lead-off from Dr. Davis):
- Real extra-virgin olive oil should be peppery and make
you cough and have a vegetal scent and flavor.
- Required: Country of Origin (USA, and USA only, which is
almost always going to be California, although the California
Olive Ranch DESTINATION,
line, lacking content from Tunisa or Spain, passed CL testing)
- Required: Ingredients list containing only olives
- Required: bottle material dark glass (not plastic)
- Required: harvest date
- Extra credit: fatty acid breakdown
- Extra credit: organic (this appears to be hard to find)
- Window-dressing: non-GMO (all olives are non-GMO, so
getting certified is a needless expense)
Terms like “extra virgin”, “cold-pressed”,
“first-press”, and even “organic” do not
protect you on this. Price does not protect you on this (but a
quality US domestic oil won’t be cheap). “Light”,
“premium”, “pure” and “natural”
might be warning labels.
Bob Niland [disclosures]
[abbreviations] Return to ToC