Fats are one of the three main macronutrients, along with proteins and carbohydrates.
Fats consist of carbon and hydrogen atoms. They are made up of collections of molecules called triglycerides. Triglycerides are formed with three fatty acids attached to a glycerol molecule.
If this collection is liquid at room temperature, it can be called an oil.
If it’s solid, it is referred to as fat.
Lipid, on the other hand, is a broad term that includes not only fats but also hormones, cholesterol, phospholipids, sphingolipids, sterols, etc.
Fats are mainly categorized either as saturated fats or unsaturated fats.
Saturated fats are fats that contain single covalent bonds between the carbon atoms of fatty acids.
Each carbon atom is bonded with a maximum number of hydrogen atoms in the molecule, hence the term ‘saturated.’
There are different names of saturated fats based on the number of carbon chains in the molecule.
The most common types of saturated fatty acids are caproic acid (6 carbon atoms), lauric acid (12 carbon atoms), stearic acid (18 carbon atoms), and a few others.
Each type has a unique characteristic and plays a unique role in the human body.
Animal fat has a higher percentage of saturated fats in them.
These fats have higher melting points, that’s why I recommend them as cooking oils. They are solid at room temperature.
Some common examples of saturated fats are butter, Ghee, coconut oil, palm kernel oil, lard.
Red meats like beef, pork, lamb, and parts of chicken also have a high percentage of saturated fat in them.
Double bonds between the carbon atoms characterize unsaturated fats.
Do note where double bonds are formed; there are fewer hydrogen atoms bonded to the carbon atom and, therefore, the term ‘unsaturated.’
Saturated fats have no double bonds, and therefore are ‘saturated’ with hydrogen atoms that are bonded with the carbon atoms!
There are two main types of unsaturated fats:
Monounsaturated Fats and Polyunsaturated Fats.
Monounsaturated Fats (MUFAs)
Monounsaturated fats (abbreviated as MUFAs) contain just one double covalent bond between two fatty acid carbon atoms. That’s the reason they are prefixed with ‘mono’ which means one.
They are liquid at room temperature. However, refrigeration may turn them into a semi-solid state (even solid).
The most common type of monounsaturated fatty acids is oleic acid. The other types are paullinic acid, vaccenic acid, etc.
They are mainly found in plant foods. The most common source of MUFAs is olive oil, almonds, cashews, peanuts, pumpkin seeds, etc.
The benefits of monounsaturated fatty acids are well-documented, and unlike saturated fats non-controversial.
Almost every expert agrees that adding olive oil (which has the highest content of MUFAs) is beneficial for heart health by increasing the HDL1<https://www.ncbi.nlm.nih.gov/pubmed/1609766> and some studies have linked it with lowered blood pressure!2<https://www.ncbi.nlm.nih.gov/pubmed/16287956>
More studies link it with decreased inflammation levels, which in turn reduces the risk of chronic diseases.3<https://www.ncbi.nlm.nih.gov/pubmed/15383514>
Polyunsaturated Fats (PUFAs)
Polyunsaturated fats (abbreviated as PUFAs) contain two or more double covalent bonds between two fatty acid carbon atoms. That’s the reason they are prefixed with ‘poly’ which means many.
They are liquid at room temperature like monounsaturated fats. However, refrigeration may turn them into a semi-solid state (even solid).
They are also found in plant foods. The most common source of PUFAs are walnuts, canola oil, seeds like sunflower, sesame, chia. Avocados are also a good source of polyunsaturated fats.
One crucial fact that I would like to point out is that all foods that are rich in fat contain a mix of different fats.
Generally speaking, animal-based foods are high in saturated fats, whereas plant-based foods are high in unsaturated fats.
Polyunsaturated fats are further sub-divided into omega-3 and omega-6 fatty acids.
Both of them are essential fatty acids, which means the human body cannot manufacture them, and therefore you must get them from your diet.
Omega-3 Fatty Acids
Omega-3 refers to the family of fatty acids in which the first cis double bond (unsaturation) closest to the methyl end is in the third position.
Three types of omega-3s are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
Animal foods such as fish, pasture-raised eggs, walnuts are high in Omega-3 fatty acids.
Omega-6 Fatty Acid
Omega-6 fatty acid is a type of polyunsaturated fatty acid with 18 carbon atoms.
The most common omega-6 is linoleic acid, an essential amino acid that the body cannot manufacture on its own.
Omega-6 refers to the family of fatty acids wherein the cis double bond closest to the methyl end is in the sixth position.
Plant-based oils are highest in omega-6 fatty acids. Some examples are soybean oil, corn oil, sunflower oil, cottonseed oil, rice bran oil, etc.
Even though Polyunsaturated fats are essential to us, when eaten in excess, they may pose health issues.
1g of fat has nine calories, and excess fat intake may lead to unwanted weight gain. We all know this.
But here, I want to specifically focus on a topic that is not talked about much.
I am referring to the Omega-3 and Omega-6 optimal ratio.
Omega-3 and Omega-6 Fatty Acids | What’s the optimal ratio?
Anthropology studies indicate that humans evolved on a diet with a ratio of omega-6 and omega-3 essential fatty acids of approximately 1!
But unfortunately, the western diet’s ratio is highly skewed, i.e., 15/1 – 16.7/1.
Many experts believe that this is a severe health problem.4<https://www.ncbi.nlm.nih.gov/pubmed/12442909>
A 2016 study indicates that this ratio may even be more skewed, i.e., 20:1 or even higher!5<https://www.ncbi.nlm.nih.gov/pubmed/26950145>
According to this study6<https://www.ncbi.nlm.nih.gov/pubmed/12442909>:
“A ratio of 4/1 was associated with a 70% decrease in total mortality. The breast cancer risk was reduced with an improved ratio. A ratio of 2-3/1 suppressed inflammation in patients with rheumatoid arthritis and a ratio of 4/1 had a beneficial effect on patients with asthma.
For optimal health, a ratio of omega-6 and omega-3 of [1-4]/1 should suffice!
The ratio in today’s western diet is skewed because of the soaring popularity of vegetable oils in the past century.
The chart below shows the consumption of different types of fats in the past hundred years.
You can see the meteoric rise in the consumption of vegetable oils (mainly soybean oil) and a downward trend for lard and butter.
Out of all the vegetable oils, soy grabbed the most market share as it’s cheap. This is why you will also find soybean oil (both liquid and partially hydrogenated) in most processed foods as well!
Soybean oil has one of the highest percentages of calories from omega-6 fatty acids. The other oils that are very high in omega-6 are:
Rice Bran Oil
Health Risks Associated With Increased Intake Of Omega-6 Fatty Acids.
Vegetable oils like soybean, corn, cottonseed, sunflower, rice-bran oils undergo a lot of processing and refinement before humans can consume them.
Most commercially available vegetable oils are converted from their respective plant-seeds using chemical solvents to make them edible.
There are scores of scientific studies that suggest that omega-6 promotes oxidative stress, causes chronic inflammation and atherosclerosis.7<https://www.ncbi.nlm.nih.gov/pubmed/9488997?dopt=Abstract> 8<https://www.ncbi.nlm.nih.gov/pubmed/5445332?dopt=Abstract> 9<https://www.jlr.org/content/50/2/204?ijkey=12c01c7e3097d64cd27b815eebd20500c613f2e7&keytype2=tf_ipsecsha> 10<https://www.ncbi.nlm.nih.gov/pubmed/17259442?dopt=Abstract> 11<https://europepmc.org/article/med/14203263> 12<https://www.ncbi.nlm.nih.gov/pubmed/8466938?dopt=Abstract>
It is also likely to increase the risk of coronary heart disease.
Polyunsaturated Omega-6 has many carbon double bonds, which makes them highly reactive and sensitive to heat, oxygen, and light. They can get easily oxidized and turn into free radicals.
What are Free Radicals? | And Why Should You Care?
Free radicals are highly unstable molecules that can play havoc in the human body. They are defined as molecules that contain an unpaired electron in its outer orbit.
Let me give you a basic chemistry lesson that will make the topic of free radicals and antioxidants (that I will discuss in a while) clear to you!
Everything in the Universe is composed of atoms. The sub-atomic particles that make up the atom are electrons, protons, and neutrons.
Protons and neutrons make up the nucleus of the atom.
Electrons are found in the shell or orbitals that surround the nucleus. They revolve around the nucleus in a circular orbit, just like the planets orbit the sun!
Now each shell of the atom needs to be filled by a set number of electrons.
Once the shell is full, the electrons start to fill up the next shell.
In the case of free radicals, its outer shell has an unpaired electron. Since electrons like to be in pairs, the unpaired electron seeks out the other electrons to bind and become a pair.
This unpaired electron in the free radicals makes them highly unstable and reactive.
They can trigger several diseases by altering proteins, lipids, DNA, and the integrity of cell membranes.
Usually, oxygen in the body splits into single atoms and becomes free radicals.
In a normal healthy human body, there is a balance between oxidative stress (free radical production) and the presence of antioxidants.
Antioxidants are molecules that donate a pair of electrons to the free radicals and render them harmless. We’ll discuss them in a while.
Coming back to free radicals, they can be produced either internally or due to external factors.
A few internal generated sources of free radical are mitochondria, inflammation, peroxisomes, phagocytosis, and exercise.13<https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3249911>
Some external sources of free radicals are cigarette smoke, air pollutants, and industrial chemicals.
Radiation, certain drugs, and consuming foods cooked in vegetable oils (omega-6 fatty acids) are some of the other external factors that cause the production of free radicals in our bodies.
Free radicals are a naturally occurring by-product of metabolism. In a healthy body, free radicals are maintained at a low level.
But when they start to build up because of wrong food choices, smoking, etc. then over time, this could lead to oxidative stress.
Excessive free radical exposure (oxidative stress) to cells can lead to increased heart risk, cancer, DNA damage, and can even accelerate the aging process.
2 Ways to Limit The Buildup of Free Radicals
-Eat Foods High in Antioxidants
Antioxidants are molecules that can donate an electron to free radicals without becoming destabilized or reactive.
The human body can produce some antioxidants on its own. However, this supply is limited. Therefore one needs to eat foods high in antioxidants to reduce the build of free radicals in their bodies.
Well-known antioxidants include Vitamin C, E, and lycopene (a compound you find in tomatoes). Overall, fruits and vegetables have the highest content of antioxidants in them!
Well, now you know why virtually every expert strongly recommends generous servings of fresh fruits and veggies every day 🙂
-Optimize your Omega-3 and Omega-6 ratio
There are two ways you can do this.
First, increase your intake of Omega-3s.
Secondly, drastically reduce the intake of omega-6 fatty acids.
The best strategy is to completely replace vegetable oils with healthier cooking oils like Ghee and coconut oil.
If you still fear saturated fats (which are high in ghee/coconut oil), then your best bet is to use extra-virgin olive oil as your cooking oil.
What do you think about this article? Have any questions?
Let me know in the comments below!
Sources & References [ + ]