All About Healthy Fats
What are healthy fats?
Fats are organic molecules made up of carbon and hydrogen elements joined together in long chains called hydrocarbons. These molecules can be constructed in different ways, which creates different types of fat and their unique properties.
There are 3 main types of dietary fat: saturated, monounsaturated, and polyunsaturated.
The difference between saturated and unsaturated fats lies in the bond structure. (See the diagram below.) Saturated fats contain no double bonds. Each carbon (C) has two hydrogens (H). The chain is “saturated” with hydrogens. Because of this chemical configuration, saturated fats are generally solid at room temperature.
Unsaturated fats, on the other hand, have one or more double bonds between the carbons. Thus not all of the carbons have hydrogens stuck to them. This puts a “kink” in the chain.
Monounsaturated fats have one double bond and polyunsaturated fats have more than one.
These molecular shapes of various fats are important, because the shapes determine how the various fats act in the body.
In popular terminology, the monounsaturated and polyunsaturated fats are what most people refer to as “healthy fats.” Yet humans have likely consumed unprocessed forms of saturated fats (such as organ meats from wild game, blubber from seals and whales, milk, or coconuts) for their entire existence. And since humans evolved by consuming a diet of whole foods, fat intake from mono-, poly-, and saturated sources was distributed evenly. (More on this below.)
Why are healthy fats so important?
Fats exert powerful effects within the body and healthy fats have been shown to offer the following benefits.
Strong evidence
- Cardiovascular protection (though there is less evidence for protecting against heart failure)
- Improve body composition
- Alleviate depression
Average evidence
- Prevent cancers
- Preserve memory
- Preserve eye health
- Reduce incidence of aggressive behaviour
- Reduce ADHD and ADD symptoms
When it comes to healthy fat, intake amount is important. People are often concerned about excess dietary fat, but not getting enough fat may also cause health problems.
We need adequate fat to support metabolism, cell signaling, the health of various body tissues, immunity, hormone production, and the absorption of many nutrients (such as vitamins A and D). Having enough fat will also help keep you feeling full between meals.
What you should know about healthy fats
Our fat history
Humans evolved on diets consisting of marine life, wild game and/or inland plants, which provided abundant omega-3 and other unprocessed fats. Early humans (and many hunter-gatherer groups today) consumed all parts of animals — including fatty tissues such as blubber, organs, and brains along with eggs from fish, fowl, and reptiles.
This resulted in an omega-6/omega-3 ratio that was around 1:1. Humans currently consume a ratio of about 16:1 – an intake that’s out of balance.
Much of our omega-6 and saturated fat intake is from refined fat sources, not from whole foods. Items like corn oil, safflower oil, and factory farmed meat/eggs/dairy contain unhealthy balances of fat. Soybean oil alone accounts for over 75% of oils consumed by Americans.
You’re a fathead… literally
Fat we consume is digested and either used for energy, stored in adipose (fat) tissue, or incorporated into other body tissues and organs.
Many of our body tissues are lipid (aka fat) based, including our brains and the fatty sheath that insulates our nervous systems. Our cell membranes are made of phospholipids, which means they’re fat-based too.
Thus, the fat we consume literally becomes part of our cells. It can powerfully influence how our cells communicate and interact.
For example, fat can affect signaling molecules that influence blood vessel constriction, inflammation, blood clotting, pain, airway constriction, etc. Since our brains are fat-based, changes in fat composition can affect transmission of nervous system impulses.
For this reason, balancing our fat intake can promote optimal functioning of our entire body. Therefore it’s important that we emphasize whole food fat sources in our diets, and supplement as necessary.
Omega-3 types
Blood levels of omega-3 fats seem to be lower in plant-based eaters than in those who eat meat, so plant-based eaters should be particularly vigilant about proper fat intake.
The most important omega-3 fats are the following:
- ALA (alpha-linolenic acid)
- DHA (docosahexaenoic acid)
- EPA (eicosapentaenoic acid)
Flax, hemp, and chia are rich in ALA while fish and algae is rich in EPA and DHA.
ALA is converted to EPA and DHA.
However, this conversion is not perfect and is relatively inefficient, especially in people who consume a typical Western diet. Thus, people who eat diets high in processed foods and refined carbohydrates, etc. will not reap many benefits from ALA.
As one study explains, “dietary oils that are rich in α-linolenic acid do not, for the most part, reproduce the biological activity associated with dietary fish oils.”
In other words, it’s probably best to get EPA/DHA from marine sources. (See AA Algae for more on plant-based sources.)
Monounsaturated fats
In addition, monounsaturated fats are important to consume as well. These are fats from other nuts, seeds, olives, and avocadoes.
One of the key benefits of monounsaturated fats is that they appear to lower LDL cholesterol (aka the “bad” cholesterol). They may also increase HDL cholesterol (aka the “good” cholesterol), but evidence for this is not as clear.
CLA
Once everything is in order with your nutrition and lifestyle, consuming CLA (conjugated linoleic acid) might be another option.
CLA resembles LA (linoleic acid) but the structure is slightly different, giving it a different effect in the body. It may help to control levels of body fat.
Food sources of CLA include pasture-raised/grass-fed animals/eggs. Plant-based CLA supplements are usually derived from sunflower oil.
Saturated fat
Saturated fat seems to support the enhancement of good cholesterol.
Fats from palm oil and coconut oil are highly saturated. Palm and coconut also contain medium chain fats, which can support health and optimal body composition.
Due to the high prevalence of animal foods and tropical oils (from processed foods) and the low prevalence of whole plant foods in the modern diet, people tend to get too much saturated fat relative to unsaturated fat, and combine these saturated fats with refined carbohydrates. Health suffers as a result.
In addition, tropical oils (e.g. palm and coconut oils) usually appear as industrially refined, hydrogenated fats in processed foods, rather than in their native form. If you choose to consume these tropical oils, make sure they are unrefined (e.g. whole coconut or extra-virgin, cold-pressed coconut oil).
Summary and recommendations
Consume foods rich in healthy fat each day. These include nuts, seeds (hemp, flax, and chia are especially nutritious), fish, seaweed, pasture-raised/grass-fed animals/eggs, olives, avocado, coconut, and cacao nibs.
Saturated fat should make up no more than 10% of total calories. If you’re eating by PN recommendations, you should have no trouble with this.
Avoid industrially processed, artificially created, and factory farmed foods, which contain unhealthy fats.
Supplement with algae oil or fish oil daily. 1-2 g of algae oil or 3-6 g of fish oil is recommended.
Taking more than 3 g/day of DHA + EPA (as the active ingredient) may promote excessive bleeding in those on blood thinners.
Omega-3 supplementation is discouraged with heart rhythm disturbances.
Further Resources
References
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