Fat gets a bad rap. Thanks to decades of trendy weight-loss plans extolling the virtues of low-fat diets, many Americans are under the misconception that all fats are bad for you, and anything fat-free is inherently healthy. The truth is, because fat makes up most of the structural elements found in each of the human body’s trillions of cells, our bodies actually require a certain amount of fat to be normally constructed and function properly. However, all fats are not the same.

Omega-3 polyunsaturated fatty acids: The skinny on critical fats 

A particularly important family of fats helping to maintain cellular health are called polyunsaturated fatty acids (PUFAs). Often referred to as “healthy fats”, PUFAs are distinguished at the molecular level from saturated and monounsaturated fatty acids by the presence of at least 1 double bond between carbons within their fatty acid chain .  Depending on the position of a fat’s first double bond, PUFAs can be named as one of 2 sub-families: omega-3 fatty acids or omega-6 fatty acids. 

Omega-3 PUFAs, particularly family members EPA and DHA, are most commonly found within cell membranes, and are removed from these membranes each day in order to contribute to a number of physiological processes critical for maintaining daily normal, foundational activity.^1,2 Despite growing evidence that inadequate intake of EPA and DHA may contribute to poor health, low levels are common among those eating a standard Western diet, characterized by a low intake of fish and seafood, and a high intake of processed foods, saturated fats, and a substantial excess of omega-6-laden vegetable oils. 

This article focuses primarily on the features and functions of omega-3 PUFAs. However, in order to appreciate their biological significance to cells and therefore general health, it’s helpful to understand the difference between omega-3 and omega-6 fatty acids, and how these two families of fatty acids interact.  

Omega-3s and omega-6s: PUFA sources 

Alpha-linolenic acid (ALA) is the parent fatty acid of the omega-3 family, and through a complex series of metabolic reactions gives rise to the long-chain fats eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Because ALA is required for cells to function normally but cannot be synthesized by the body, it is called an essential fatty acid. ALA must be consumed through dietary sources including:

• Flaxseeds, camelina seeds, perilla seeds, chia seeds, hemp
• Canola oil, flaxseed oil, walnut oil  
• Walnuts, pecans 

Although EPA and DHA can be synthesized from ALA, their conversion rates are so low that they are considered conditionally essential or necessary nutrients. This means that EPA and DHA are physiologically necessary for balanced, normal cell structure and function, and therefore ultimately necessary for good health.³ Because the body is extremely limited in its ability to convert EPA and DHA from ALA, it is generally recommended^4,5 that EPA and DHA be obtained directly through dietary sources including:

• Cold-water fatty fish (tuna, sardines, salmon, mackerel)
• Fish oil (EPA+DHA supplements) 
• Plant-based sources like algae or algae oil 

Nordic Naturals offers a broad range of high-quality omega-3 supplements from fish oil and algae to meet individual dose and delivery-form needs.

Linoleic acid (LA) is the parent fatty acid of the omega-6 family and is transformed through a complex series of metabolic reactions into the long-chain omega-6 fatty acid arachidonic acid (AA) and other omega-6 PUFAs.  Similar to ALA, linoleic acid (LA) cannot be made by the body and is therefore called an essential fatty acid that must be obtained from the diet.  Primary sources of LA include certain vegetable oils (soybean, corn, safflower, canola), nuts and seeds, avocados, and animal meats. While “vegetable” oils may sound nutritious, keep in mind that most of the foods containing vegetable oils contain fatty acids that have been structurally changed in some way. As a result, foods containing these altered oils (e.g., baked goods, fried foods, chips and other packaged snacks, etc.) may have limited health benefits compared to fats in their native state.

Although LA and AA serve important structural and physiological functions—especially for skin health and during early brain development^6,7—when consumed in great excess these fatty acids can contribute to a host of negative health effects.^2,8 Conversely, a tremendous amount of research shows that consuming an appropriate balance of omega-3 and omega-6 fats can help balance omega-6 and omega-3 levels in cells and tissues.  When balanced, these fats may help to improve cell structure and function, and ultimately contribute to a wide variety of health benefits.   

Importantly, because both classes of fatty acids compete for the same enzymes needed to synthesize their PUFA derivatives, an increase in the content of omega-3 within a cell typically occurs at the expense of omega-6, and vice versa.² Understanding how the amount and type of fats consumed in the diet affects the amount and type of fats making up your cells is very important, as these fats may influence many aspects of health in both the short- and long-term.

Effects of PUFAs on cell membrane structure and function 

Omega-3s play important roles throughout the body as structural components of cell membranes. When dietary intake is appropriate, both EPA and DHA are common in cell membranes throughout the body. (In contrast, DHA alone can be found in very high concentrations in the retina and the brain, implicating its important role in vision and general nervous system function.)⁹ Cell membranes are made up of 2 layers of a diverse group of similar-shaped molecules called phospholipids, which directly or indirectly influence nearly every aspect of a cell’s daily activity.  After EPA and DHA are consumed through the diet, after digestion, absorption, and transport they are placed within a membrane phospholipid, where they can affect cellular function by promoting the fluidity, flexibility, and/or the permeability of a membrane.¹⁰ These features are vital to numerous daily cell operations including receiving, processing, and responding to information from nearby cells and messages coming from the surrounding environment.^10,11 Similarly, omega-6 fatty acids are placed within membrane phospholipids, and also can contribute to important structural effects that promote fluidity, flexibility and permeability. 

Some of the most important differences between omega-3 fatty acids (EPA, DHA) and omega-6 fatty acids (such as AA) appear after these fats are removed from cell membranes.  After being removed from cell membranes and deported into a cell’s interior, individual omega-3 and omega-6 fatty acids are converted into powerful signaling molecules that help regulate short-term processes that influence how a cell responds to stress. In general: 

• Signaling molecules made from the omega-6 fat arachidonic acid (AA) help initiate processes that may promote short-term cellular stress
• Signaling molecules derived from the omega-3 fats EPA and DHA help initiate processes that may reduce short-term cell stress⁸

Omega-3 research: Evidenced-based health benefits  

Thousands of laboratory and clinical research studies link consumption of EPA and DHA to an array of significant health benefits. The studies highlighted in the next few sections provide an overview of key evidence-based findings and benefits that have been associated with the use of these omega-3 PUFAs.

Omega-3s and Cardiovascular health

A strong body of evidence has demonstrated that EPA and DHA provide benefits for certain aspects of cardiovascular health. Documented benefits of EPA and DHA for heart health include:

• Promoting overall cardiovascular health*^12,13
• Helping to maintain normal levels of fats in the blood within the normal range*¹⁴
• Promoting the normal structure and activity of blood vessels*^14,15,16
• Helping to maintain a healthy and regular heartbeat*¹⁷
• Helping to maintain a healthy and regular heartbeat*¹⁷
• Promoting healthy arterial blood flow and the normal functioning of platelets*^18,19

Discover Nordic Naturals full lineup of expertly- formulated supplements containing EPA & DHA, plus other complimentary nutrients for heart health support.

Omega-3s & Immune health

Short-term (acute) cellular stress responses are a normal and necessary physiological response that begins a very complex process designed to restore cellular health and physiological balance in susceptible tissues throughout the body after exposure to stressors. If, however, these cellular stress responses continue beyond the needed time frame, they can contribute to poor health.^2,8,9

Fatty acids play important roles within this story of short-term and long-term cell stress responses. After removal from cell membranes, the powerful signal molecules made from the omega-3 fatty acids EPA and DHA act to help lower cell stress responses. In contrast, after removal from cell membranes, the powerful signal molecules made from the omega-6 fatty acid arachidonic acid (AA) act to help raise cell stress responses.  Both are necessary for a normal response to cell stress: when a disturbance occurs, omega-6 signal molecules help the local tissues mobilize and begin the repair work. Importantly, the signal molecules from EPA and DHA help this process to remain within reasonable boundaries and resolve rather quickly (typically within a matter of days).  

A person’s fat intake influences this process by providing the fats that reside within a cell’s membrane, and thus, the ones that will be removed and used.  If omega-6 fatty acids are more abundant within a cell’s membrane, then signal molecules that help promote a cell stress response will be more common. In contrast, if omega-3 fatty acids are more abundant within a cell’s membrane, then signal molecules that help lower a cell stress response will be more common. Research suggests that cells need both fatty acids, but that an abundance of omega-3s is more favorable for maintaining a healthy cell response to stress. In sum, with an appropriate balance of fatty acids in membranes throughout the body, cells have the potential to function more normally.  Because organs are made up of cells, organs will also have the potential to function more normally.  And because normal organ functioning is associated with greater general health, obtaining a sufficient amount of omega-3 fats can help support overall health. 

Omega-3s, the Brain, and Mental health 

By weight, over half of the brain is composed of fats (lipids), with DHA representing 10-20% of this fat.⁵ The prevalence of DHA in the brain and other nervous tissues and a wealth of laboratory and clinical research combine to suggest that this molecule plays integral roles during human development, while helping to promote the healthy structure and function of nervous system components throughout life.²⁰ Evidence from clinical trials, observational studies, and meta-analyses have found that EPA and DHA may: 

• Support healthy brain function and cognitive development in infants and children*^21-23 
• Help maintain normal levels of attention and focus*^24,25 
• Support a normal mood balance and overall mental health*^26,27
• Supports healthy brain structure, normal memory, and neurological functioning into older adulthood*^28-32

Explore Nordic Naturals brain and memory supplements to support child development, cognition and memory, mood health, and more.*

Omega-3s, Pregnancy, and Neonatal development

The life journey begins with fetal development during pregnancy, and similar to adults, a sufficient abundance of omega-3 fatty acids appears to be beneficial for a fetus’s cellular health. Research has found that DHA accumulates rapidly in the brain and retina during the latter part of gestation and during the first several years of postnatal life.  Studies have also found that supplementing with DHA may promote a woman’s chances of carrying a baby to full-term (for more information about DHA during gestational development, refer to “Why Do I Need DHA During Pregnancy?”).  Further evidence suggests that omega-3s, particularly DHA, work to: 

• Help promote a healthy pregnancy*^33-35 
• Support normal gestation duration and birthweight*^35,36 
• Support normal fetal development*^22,36

If you’re seeking high-quality nutritional support for the toughest job there is—pregnancy and early childhood – Nordic Naturals expertly formulates omega-3 products with DHA for prenatal health and for your baby’s growing brain, eyes, and nerves.*

Conclusion 

To make a long story short, many research studies converge on the findings that omega-3 PUFAs are necessary for maintaining normal and balanced cellular and metabolic health. While it’s important that we consume both critical PUFAs, research suggests that consuming sufficient EPA and DHA daily is integral for foundational health, and that supplementation through dietary sources—including fish oil—can lead to significant health benefits.

Every cell in the body relies on omega-3 fatty acids to function well*. Look to Nordic Naturals, the #1 selling fish oil brand in the U.S.‡ , for a full range of omega-3 supplements. 

FDA Disclaimer:
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

‡ Based on Stackline, Nielsen, and SPINS annual sales data

General Notice & Disclaimer: 
This information is for educational purposes only. Always consult your health care provider if you have a known medical condition or are taking medications. The information provided herein is based on a review of current existing research; the presenter and sponsor do not accept responsibility for the accuracy of the information itself or the consequences from the use or misuse of the information.