by Matt Weik, BS, CSCS, CPT, CSN
Omega fatty acids have been a major topic of discussion lately, and it brings up linoleic acid and puts it on the chopping block. But is it really bad for you?
Many believe that too much omega-6 fatty acids can cause inflammation and heart disease. However, it’s important to understand that omega-6s, like linoleic acid, are not only essential for brain function, metabolism, and development but also play a significant role in our overall health.
In Western countries, the intake of omega-6 fatty acids often surpasses the recommended amount, leading to a focus on their adverse effects, which isn’t really an issue when you look at Eastern countries.
Consuming organic, non-GMO sources of linoleic acid can lower cardiovascular disease risk, improve brain health, and enhance reproductive health. Linoleic acid, making up about 90% of dietary omega-6s, is crucial in many biochemical processes.
Linoleic acid may seem like a complex subject that many feel goes over their heads, but it’s quite significant. It comprises 6-10% of the calories in our diets today, yet its impact on health has yet to be widely understood.
In this article, we will dive deeper and learn everything you should know about linoleic acid and whether it’s good for you or not.
Disclaimer: This article is for informational purposes only and is not meant to treat or diagnose any condition. It is recommended that you speak with your doctor before starting any exercise program, making changes to your nutrition plan, or adding any new supplements into your current routine.
What is Linoleic Acid?
Linoleic acid, an omega-6 polyunsaturated fatty acid (PUFA), is found in many foods, especially nuts, seeds, and seed oils.
As a primary component of vegetable oils, it’s a major calorie source in many processed foods. It also enhances the sensory properties of foods by carrying flavors and altering textures.
Linoleic acid is liquid at room temperature, colorless or lightly straw-colored, and usually flavorless or slightly bitter. It’s molecularly unstable and prone to oxidation during storage and heating, which can increase its bitterness when rancid.
As an essential fatty acid (EFA), linoleic acid must be obtained through diet since the body cannot produce it. Another essential fatty acid, α-linolenic acid, is an omega-3 fatty acid also required through diet.
Linoleic acid is also known as C18:2 or C18:2n6 (omega-6), reflecting its chemical structure of 18 carbon atoms and two double bonds. Unlike monounsaturated fatty acids (e.g., in olive oil) with one double bond, linoleic acid is polyunsaturated, containing multiple double bonds.
The Benefits of Linoleic Acid
Here are some of the benefits of Linoleic Acid.
1. Reduce Cardiovascular Disease Risks
Consuming linoleic acid may lower LDL cholesterol, improve blood pressure, and reduce cardiovascular disease risk. The American Heart Association recommends 5-10% of energy from omega-6 fatty acids, primarily linoleic acid, to lower cardiovascular risk.
A 2014 University of Minnesota analysis of over 310,000 subjects found that high dietary linoleic acid correlated with a 15% lower risk of coronary heart disease. Replacing 5% of energy from saturated fats with linoleic acid reduced coronary heart disease events by 9% and death from coronary disease by 13%.
2. Skin and Hair Health
A linoleic acid deficiency can cause scaly, itchy skin. One benefit of linoleic acid is that it can maintain skin hydration, aid in wound healing, and reduce inflammation and acne.
Oils high in linoleic acid, like safflower and argan oil, may promote hair growth and treat thinning hair. Linoleic acid is a precursor of arachidonic acid, which supports hair growth.
3. Brain Health
Linoleic acid isn’t just a dietary component but a crucial player in brain health as well. It’s essential for cell membranes, playing a role in brain function. Research shows increased brain linoleic acid after an injury, indicating its role in the brain injury response.
Animal studies suggest linoleic acid’s involvement in neurotransmission and ischemic brain injury response and its importance.
Low linoleic acid levels are linked to mood disorders, with reduced concentrations found in the brains and platelets of suicidal individuals. That said, we can’t simply say that linoleic acid will stop an individual from doing the unthinkable.
4. Boosts Immune Function
Omega-6 fatty acids, including linoleic acid, may enhance immune function and regulate cellular immune reactions, potentially reducing autoimmune disease severity. This benefit is seen with a healthy omega-3 to omega-6 balance.
That said, an excess of omega-6 can cause a pro-inflammatory response.
5. Reproductive Health
Linoleic acid deficiency impairs reproductive health. It can influence reproductive processes and prostaglandin production.
An animal study found linoleic acid supplementation improved reproductive performance and estrogenic activity, suggesting benefits for postmenopausal symptoms.
Is Linoleic Acid Good or Bad for You?
While consuming 1-2% linoleic acid is essential for survival, it’s important to be aware that higher intakes are linked to a range of health issues, including inflammation, heart disease, cancer, dementia, diabetes, and obesity.
Today, people consume more linoleic acid than ever before. Historically, most didn’t eat vegetable or seed oils high in linoleic acid, getting enough from nuts, grains, meat, eggs, and dairy naturally through their diet. It’s important to be mindful of your dietary choices and strive for a balanced intake of essential fatty acids.
A study in the American Journal of Clinical Nutrition showed a 1000-fold increase in soybean oil consumption (about 55% linoleic acid) from 1909 to 1999. This increase, alongside other industrial omega-6 seed oils, has led people to consume 6-10% or more of their calories from linoleic acid, with trends suggesting further increases.
The problem with high linoleic acid intake is its instability as an omega-6 polyunsaturated fatty acid. It oxidizes quickly during manufacturing, storage, cooking, and within the body, leading to cellular instability and inflammation. Excess linoleic acid accumulates in cells, causing more inflammation.
Overconsumption also disrupts the balance between omega-6 and omega-3 fats, depleting anti-inflammatory omega-3s. It’s important to maintain a healthy balance between these two types of fats in your diet.
Researchers believe humans evolved to consume equal amounts of these fats, but modern diets often have 20 times more omega-6 than omega-3, unfortunately disrupting cellular function and promoting inflammation.