The immune system encompasses a diverse group of cells that perform important immunity-enhancing functions throughout the body.
Research suggests that omega-3 fatty acids EPA and DHA can help regulate immune functioning and enhance overall health.
Increasing your intake of immune-boosting nutrients and dietary factors is a prudent strategy for optimising your immune health.
Natural strategies for strengthening the immune system are in high demand these days, and it’s not hard to see why. As the world prepares itself for the uncertainty of what lies ahead, one thing is for certain: actively working to maintain a healthy immune system is a trend we’d all be wise to follow. Not only for the health of ourselves, but for the health of our communities.
But does that mean you should take every supplement that claims to enhance immune health and drink your weight in orange juice every morning? Not exactly.
While getting a healthy daily dose of vitamin C is certainly a tried-and-true method for boosting immune health, there are other nutritional strategies you can adopt to give your immune system an added advantage. But before we jump into the nutritional research, let’s quickly review what the immune system is, and how it helps protect the body from invading pathogens.
Immune System 101: What is it and how does it work?
Put simply, the immune system is a defense system that helps protect the body from invading pathogens, such as viruses and bacteria. It encompasses a diverse group of immune-related cells that can be broadly categorised as either innate or adaptive immune cells, based on their different properties and mechanisms.1
Innate immune cells (such as macrophages, neutrophils, and NK cells) serve as the body’s first line of defense against pathogens. Although they are quick to respond to threats, innate immune cells carry out less specific responses to individual pathogens.2
Conversely, adaptive immune cells (namely T cells and B cells) are slower to respond but produce and respond to antibodies, which enables the immune system to remember past infections for future defense. For example, B cells develop antibodies against the pathogens they encounter, which enable them to respond more efficiently during a second encounter.2
Importantly, how well these different immune cells are able to coordinate their activities determines how effectively the host can mount an immune response, and ultimately, their ability to stay healthy. One of the ways immune cells typically accomplish this task is by secreting cytokines —molecules that attract other immune cells to the site of infection and regulate their activation or suppression.3,4
So, what factors contribute to the quality of a body’s immune response? Although a number of different variables (e.g., age, underlying health, stress levels, sleep habits, etc.) contribute to an organism’s immune health, the importance of proper nutrition cannot be overstated.5 Let’s discuss some of the nutrients and dietary factors that have been found to have immune-regulatory effects, and benefits for immune health.
When you think nutrition for immune health, your mind probably goes straight to vitamins and minerals, right? Well, not so fast—mother nature has more than a few “tricks” for optimising immune health up her sleeve. One such trick is increasing your omega-3 intake. Indeed, research indicates that the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can promote immune health by reducing cell stress responses that lead to suboptimal health and enhancing the function of immune cells.6
Omega-3s Help the Body Respond to Cellular Stress
Short-term cell stress responses are a normal and necessary physiological response that help the body initiate processes designed to restore damaged body cells and tissues after an injury, infection, or illness. However, if these cell stress responses (often referred to as the body’s inflammatory response) become long-term, they can damage cells and tissues, and ultimately contribute to a variety of chronic health problems. 7,8
That’s where omega-3s come in.
Because of their ability to synthesise potent signal molecules that help lower cell stress responses, fatty acids such as EPA and DHA can help the body return to normal after a threat has passed.9 In contrast, the potent signal molecules made from the omega-6 fatty acid arachidonic acid (AA) serve to help raise cell stress responses.10
This means that if omega-6 fatty acids are more abundant in cell membranes, then signal molecules that help promote a cell stress response will be more common. Conversely, if omega-3 fatty acids are more abundant, then signal molecules that help lower a cell stress response will be more common. Although cells need both types of fatty acids to function, research suggests that having an abundance of omega-3s is favourable for maintaining a healthy cell response and overall immune health.7,9,10
Given the prevalence of foods containing omega-6 fatty acids (e.g., processed snacks, vegetable oils, red meat, etc.) most people have a far higher ratio of omega-6 fatty acids than omega-3 fatty acids in their cell membranes.
Fortunately, supplementing with dietary sources of omega-3s (e.g., fatty fish, algae oil, or fish oil) can help balance this ratio and the body’s response to cellular stress.10
Omega-3s Enhance Immune Cell Function
Another important way that omega-3s promote immune health is by enhancing the function of both innate and adaptive immune cells.6 For example, DHA and EPA can help regulate the activities of macrophage cells, which play a critical role in the body’s innate immune defense by patrolling for invading pathogens and working to eliminate them.11 Omega-3s also promote innate immune function by increasing the number and phagocytic capacity of neutrophil cells—a process wherein the cell essentially destroys a virus or infected cell by binding to it and engulfing it.12,13
Studies also show that EPA and DHA can enhance adaptive immune function by promoting the growth and specialisation of certain types of T cells14,15 and increasing the number and percentages of B cell populations in different tissues.16,17
All these actions mean that Omega-3s can target both inflammation and oxidation while also regulating and balancing immune cell function.
Gina Jaeger, PhD is a Developmental Specialist and Lead Research Writer for Nordic Naturals. She holds a doctorate in Human Development, and has published several research articles on children’s cognitive development. Gina enjoys studying and educating others on strategies for optimising health and wellness throughout the lifespan.
Glossary & References
Adaptive immune cells: Highly specialized lymphocytes (B cells and T cells) that eliminate pathogens or prevent their growth by neutralizing the virus or killing the virus-infected cell.
Antibodies: Specialized proteins produced and secreted by B cells that bind onto antigens in order to protect the body from foreign invaders.igh-specialized lymphocytes (B cells and T cells) that eliminate pathogens or prevent their growth by neutralizing the virus or killing the virus-infected cell.
B cells: A type of white blood cell that develops in the bone marrow and destroys pathogens by producing and secreting antibodies to specific pathogens.
Bioavailability: The proportion of a substance that enters the circulation when introduced into the body and is able to have an active effect.
Cytokine: Proteins and peptides that are secreted by cells and have a specific effect on the interactions and communications between cells.
Endogenous: Growing or originating from within an organism.
Gene expression: The conversion of genetic information into molecules that carry out the genetic instructions. When a gene is expressed, it is considered to be “active”.
Innate immune cells: White blood cells designed to prevent infection and eliminate invader pathogens through a number of non-specific mechanisms; includes macrophages, neutrophils, dendritic cells, NK cells, basophils, eosinophils, Langerhans cells, mast cells, and monocytes.
Intestinal epithelium: A dynamic cellular layer that serves as a barrier between the contents of the intestines and the underlying immune system.
Macrophage: A type of white blood cell responsible for the detection and destruction of bacteria and other harmful organisms.
Neutrophil: A type of white blood cell that helps heal damaged tissues and resolve infections.
NK cells: A type of white blood cell that plays a major role in the host-rejection of virally infected cells.
Pathogenic: Capable of causing disease; usually refers to a virus, bacteria, or other type of germ.
Phagocytic: A process wherein a cell (typically a macrophage or neutrophil) destroys a virus or infected cell by engulfing it and initiating adaptative immune responses.
T cells: A type of white blood cell which develops in the thymus gland and plays a key role in the adaptive immune system by tailoring the body’s immune response to specific pathogens.
Schutlz KT, Grieder F. Toxicol Pathol, 1987. 15(3): p: 262-264.
Alberts B, et al. Molecular Biology of the Cell, 2002. 4th edition. New York: Garland Science.