What’s the difference between omega-3’s, 6’s and 9’s?
Over 20 years ago, many of you may recall hearing a lot about the health benefits
of omega-6’s in the American diet. Nowadays, you might be wondering why everyone’s
trumpeting omega-3’s. Then there’s
the Mediterranean diet, which has
stood the test of time, but the heart of the diet — olive oil — is richest
in omega-9’s! Let’s face it, the numbers are confusing. But which fatty
acid is best for a healthy body? And what’s the difference between them?
In a nutshell, the difference between one fatty acid and another comes down to tiny
molecules. Slight differences in molecular configuration allow each of these fatty
acids to work wonders in their own unique ways, which is why it’s best not
to think about one being better than another — instead, let’s go into
more detail why a good balance of all three is so favorable to your health.
Fatty acids and their numbers
All fat is made up of fatty acids, and all fatty acids are composed of chains of
carbon (C), hydrogen (H) and oxygen (O) atoms. When we get down to the molecular
level, we see that fatty acids have long, fatty tails that bend about in different
directions. Some are straight as an arrow, with no double bonds — these are
the saturated fatty acids. The other group has varying numbers of double
bonds that make them bend to varying degrees — some even touching their toes.
These include the unsaturated fats, also referred to as monounsaturated
fats (MUFA’s), which have one double bond; and the polyunsaturated
fats (PUFA’s), meaning there’s more than one double
Fatty acid names and numbers also correspond to the number of C atoms they contain,
and designate where and how they bond and twist together with H and O atoms. Omega-3,
6 and 9, for example, are all unsaturated fatty acids with double bonds in the 3,
6, or 9 positions, respectively.
This matters because the configuration of a fat molecule’s single and double
bonds has major implications for its properties and effects in our bodies —
for better or worse! A closer look at the three big omegas should help clarify some
of these implications.
The difference between omega-3’s, 6’s and 9’s — parents
Omega-3 fatty acids are extremely important for our health — probably the
most important of the three. One major reason for this is because they
tend to suppress inflammation, which is the cause of so many of the degenerative
diseases that plague us. They do this by countering the pro-inflammatory
effects of omega-6’s, which we’ll talk about next.
Table of major fatty acids
Alpha linolenic acid (ALA, or more commonly LNA) —
Eicosapentaenoic acid (EPA)
Gamma-linolenic acid (GLA)
Docosahexaenoic acid (DHA)
Arachidonic acid (AA)
Our bodies cannot make the “parent” molecule for omega-3 fatty acids,
alpha linoleic acid (ALA – in blue in table
to right), on its own. Therefore, this omega-3 — ALA — is considered
an “essential” fatty acid. Downstream, the parent ALA gets metabolized
into the two most beneficial fatty acids: eicosapentaenoic acid (EPA) and
docosahexaenoic acid (DHA). It would be difficult to oversing the praises
of EPA and DHA, which have powerful anti-inflammatory effects, along with playing
a range of other crucial roles in the body.
Because the parent ALA is not manufactured by our bodies, and because it isn’t
all that readily converted to its “offspring” EPA and DHA either, it’s
critical that we get these fatty acids through our diets. What complicates the matter
is that these omega-3’s are the ones most lacking in our modern diet. Nonetheless,
they can be consumed in foods such as wild-caught salmon, mackerel, anchovies, walnuts,
flaxseed and green leafy vegetables — we just have to remember to include
these foods in our daily choices. In addition, they can more readily be obtained
through high-quality omega-3 supplements.
(See the benefits of omega-3’s
for more about why women of all ages need ample EPA and DHA, as well as a list of
foods rich in o-3’s
and tips on choosing
the best omega-3 supplement.)
As in the family of omega-3’s, there’s one member of the omega-6 family
that plays the role of the parent (essential) fatty acid: linoleic acid
(LA – in blue in table above). What’s different
about LA is that it is not as difficult to find in our typical American diet as
ALA. In reality, most of us get too much omega-6’s in our popular foods. Omega-6’s
can be found abundantly in many of our common vegetable cooking oils: soybean oil,
sunflower oil, canola oil and corn oil (but not olive oil). They’re also common
ingredients in many of the foods we consume, which is why most of us have a heavily
imbalanced ratio of omega-6’s to 3’s.
The ratio of 6’s to 3’s is an important consideration for your health
because LA tends to gear up the inflammatory process. If you’ve read
our series of articles on the ups and downs of
inflammation, you know how crucial the inflammatory process is to survival,
but also how it requires — as do all cycles in living systems — an efficient
set of checks and balances. Without effective and timely up-regulation and down-regulation
through a balance between o-6’s and o-3’s, inflammation can become chronic
and problematic, leading to heart disease, diabetes, and Alzheimer’s —
to name a few.
Omega-9’s are the most abundant fatty acids of all in nature, and they are
not in short supply in our diets. They are also not considered essential
because our bodies can make omega-9’s from unsaturated fat in our bodies.
Omega-9 fatty acids can be used by the body as a substitute for omega-3’s
or 6’s if these essential fats are not present. However, omega-9’s really
aren’t an ideal replacement for 3’s and 6’s, and the body will
eventually suffer from this.
Omega-9’s are found in animal fats and vegetable oils, most notably olive
oil. Interestingly, the oil made by our skin glands is the same omega-9 fatty acid
found abundantly in olive oil: oleic acid. Olive oil also contains a saturated
fatty acid known as palmitic acid, but no 6’s or 3’s. We have
stacks of data on the wondrous disease-prevention powers of olive oil, but this
research is pointing to its high polyphenol content rather than to its
fatty acid content as the origin of its superb health benefits. Every day we’re
hearing more about the strong antioxidant, anti-inflammatory, anticlotting and antibacterial
effects of polyphenols in the body. (See our page on the
Mediterranean diet for pointers on this delicious style of eating.)
Omega-3’s and essential fatty acids (EFA’s) — a clarification
If you’re like most people, you’ve heard so much about both omega-3’s
and EFA’s that you probably assume they’re one and the same. Not exactly.
There’s only one omega-3 fatty acid (alpha linolenic acid, abbreviated
LNA or ALA) and one omega-6 fatty acid (linoleic acid, or LA) — the
“parents” described above, and shown in blue in the table — that
are truly essential, because our bodies cannot make these molecules on their own.
All the other 3’s and all the other 6’s, plus all
the omega-9 fatty acids can be made in the body and need not come from
Our bodies just don’t readily convert ALA into its more useful derivatives
DHA and EPA. Of interest is that some scientists believe it’s likely humans
were able to make these conversions more efficiently in the past than most modern
people do. Today we have a few factors working against us in this regard, including
chronic stress and trans fats to name just two. And, while ALA has good anti-inflammatory
effects, it simply does not work the same way in the body as EPA and DHA.
So don’t be confused by EPA/DHA supplement labels that read “essential
fatty acids.” Just zero in on quality, purity, and the amount of EPA and DHA
they contain. (For more guidance on
how to choose an omega-3 supplement, read our full article.)
An omega balance is best
All fatty acids hold enormous potential for the body, in that they are converted
into other molecules that perform vital roles in regulating, mediating, inducing
and countering myriad body functions. It’s not so much that one omega is inheritantly
bad and another good; we just need them in the proportions Mother Nature spent so
much time — 40,000 years or so! — meticulously fine-tuning.
The problem is that adherents to the typical American diet take in stacks of omega-6’s
and 9’s, which, if not balanced by 3’s, fiercely fuels the inflammatory
fires. And we know this can lead to a litany of health issues. The ratio of omega-6’s
to 3’s should be somewhere between 2:1 and 4:1. Instead, most of us are getting
somewhere between 10:1 and 30:1.
This overview of the differences between omega-3’s, 6’s and 9’s
should give you a better idea as to why we hear so much about one fatty acid versus
another. Fortunately, there’s a simple solution for evening out the imbalance
that, unlike pharmaceutical anti-inflammatories or statin drugs, doesn’t involve
risky side effects. It’s possible to quickly and effectively quiet much of
the body’s inflammatory response directly by taking EPA and DHA supplements.
When balance between the two sides of the inflammatory cascade is restored, inflammation
is reduced and better health more readily achieved.
Related to this article:
References & further reading
on the differences between omega-3’s, 6’s and 9’s
Last Modified Date: 04/20/2011
Principal Author: Marcella Sweet