Did You Know You Have Two Types of Immune Systems?

The immune system consists of two main components—the innate and adaptive immune systems. Think of the innate immune system as the first line of defense—it is nonspecific and responds in the same way to all pathogens. In contrast to the fast-acting innate immune system, the adaptive immune system takes longer (days to weeks) and is highly targeted.

What Does the Immune System Consist Of?

The immune system can be categorized into two types—the innate and adaptive immune systems.

The innate immune system is the first line of defense—it is nonspecific and responds in the same way to all pathogens. It includes physical barriers, such as the skin and mucous membranes, as well as different types of specialized cells. This nonspecific mechanism mobilizes within minutes to hours.

In contrast to the immediate response of the innate immune system, the adaptive immune system takes longer (days to weeks) and is highly targeted. It forms antibodies against proteins on the surface of a pathogen—called antigens—and creates an immunological memory that results in a faster response if the same pathogen is reencountered.

How Did We Get Here? A Brief History of Our Understanding of the Immune System

Science began formulating theories about our immune system around the mid-19th century, at the same time that infectious diseases were discovered. Two competing positions emerged: Elie Metchnikoff, a Russian embryologist, hypothesized that cells called phagocytes engulfed and destroyed pathogens. This was the basis of what we now know as the innate immune system—cells and molecules that rush to the site of infection as part of the body’s immediate and nonspecific response to an invader. At the same time, a German biologist, Paul Ehrlich, espoused the idea of antibodies in the blood—this came to be known as the adaptive immune system, which involves cells targeted to a specific pathogen and maintains a ”memory” of invaders.

Both scientists were correct, but Metchnikoff’s theory turned out to be a precursor to Ehrlich’s, as the adaptive immune system evolved after the innate immune system. It’s known as the “big bang of immunology,” and occurred about 450 million years ago. The two scientists shared a Nobel Prize for their discoveries, and the base of our understanding of the immune system was established.

Am I Born With a “Good” or “Bad” Immune System?

You’re not born with a “good” or “bad” immune system—immunity is plastic and your immune system can be supported in different ways. First and foremost, of course, is a healthy lifestyle—managing stress, getting proper exercise, and a good diet are all critical to a healthy immune response.

Additionally, micronutrients play critical roles at every stage of the immune response. For example, collagen, the most abundant protein in our bodies and the “glue” that holds together our skin, the first line of defense in the innate immune system, cannot be synthesized without vitamin C. If collagen biosynthesis is not functioning properly, the body has a harder time repairing skin and protecting against pathogens. Vitamin C is also involved in the creation and normal functioning of innate immune cells. Zinc and selenium are also crucial: they each stimulate antioxidant activities to counter the effects of free radicals produced during the immune response to pathogens. Ensuring you’re getting sufficient micronutrients is pivotal to a functioning immune system.

Finally, there are novel therapeutics being developed as part of cutting-edge research, including senolytics which target senescent cells that accumulate in the body as we age and interfere with immune function. Our immune-aging product Format uniquely combines foundational immunity ingredients such as vitamin C, zinc, and selenium with senolytic ingredients that promote the clearance of senescent cells.


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