Having a strong immune system is vital for staying healthy and fighting off infections and diseases. But is there such a thing as having an immune system that’s too strong? Can boosting your immune system backfire? Let’s take a look at the evidence.
What is the immune system?
The immune system is your body’s defense against bacteria, viruses, and other invaders that can make you sick. It’s a complex network of cells, tissues, and organs that work together to protect the body. Here are some key players:
- White blood cells, including lymphocytes like T cells and B cells that directly detect and destroy foreign invaders.
- Antibodies, which are proteins made by B cells that recognize and neutralize threats.
- The complement system, a group of proteins that assist antibodies.
- The lymph nodes, spleen, bone marrow, and thymus, which produce and mature immune cells.
- The skin and mucous membranes, which act as physical barriers.
In a healthy immune system, all of these components work in concert to identify threats, get rid of infected or cancerous cells, and remember past attackers to prevent future illness. But what happens when the immune system gets too aggressive?
Is there such a thing as an overactive immune system?
Yes, it is possible for the immune system to become overactive and start attacking the body’s own tissues in addition to foreign invaders. This is called autoimmunity.
Normally, the immune system can tell the difference between your own cells and foreign cells. But in autoimmune disorders, something goes wrong and the body’s immune defenses mistakenly target healthy cells, tissues, and organs.
Over 130 different autoimmune diseases have been identified, including:
- Rheumatoid arthritis
- Lupus
- Type 1 diabetes
- Multiple sclerosis
- Inflammatory bowel disease
- Psoriasis
In these diseases, the immune system attacks parts of the body such as joints, skin, nerves, or organs. This causes inflammation and damage over time. Many autoimmune conditions are chronic or lifelong illnesses.
What causes autoimmune disorders?
Researchers don’t fully understand what triggers autoimmune disease. It likely involves a combination of genetic and environmental factors, such as:
- Family history. Some autoimmune diseases run in families, indicating genes play a role.
- Viruses or bacteria. Certain infections are linked to autoimmune disorders.
- Hormones. The onset of some autoimmune diseases correlates with hormonal changes.
- Exposure to toxins. Environmental toxins are hypothesized to provoke autoimmunity in some people.
- Gut health. An imbalanced microbiome may impact immune regulation.
- Stress. Physical and emotional stress can negatively affect immune function.
In a susceptible person, one or more of these factors may disrupt normal immune control, allowing self-targeting immune cells to proliferate and attack body tissues.
Can you make your immune system too strong?
There are a few key reasons why efforts to boost general immune function could potentially backfire and tip the scales towards autoimmunity:
- Overactive immune cells. Attempting to ramp up the number and activity of immune cells could make them more likely to overreact against harmless substances in the body.
- Increased inflammation. Immune stimulants often promote higher levels of inflammation. Too much inflammation directed inward can spur autoimmune reactions.
- Imbalance. Bolstering some arms of immunity but not others may disrupt the immune system’s usual homeostasis and checks and balances.
- Oxidative stress. Some products meant to enhance immunity generate reactive oxygen species that trigger cellular damage and autoimmunity.
So while giving a general boost to the immune system might seem beneficial, it could tip the scales in an autoimmune direction for predisposed individuals. It’s all about balance.
Can specific immune boosting backfire?
In addition to generally revving up the immune system, another concern is the impact of activating specific immune components in isolation. Two examples of interventions that could potentially promote autoimmunity include:
1. Antibody boosting
Antibodies, which are immune proteins made by B cells, typically bind to foreign invaders and mark them for destruction. But some antibodies can also target the body’s own cells.
Methods that non-specifically ramp up antibody production or introduce antibodies from external sources may upset the normal balance of antibodies and increase the chance of autoimmune reactions.
2. Toll-like receptor activation
Toll-like receptors (TLRs) are proteins on immune cells that detect threats and trigger inflammatory responses. But overstimulating TLRs, especially TLR4 and TLR9, has been associated with autoimmune diseases in research studies.
Some researchers theorize that overly activating TLRs could reduce immune tolerance and increase autoreactivity.
So while temporarily pumping up antibodies or toll-like receptors could give immunity a jolt, it might also dysregulate immune function and provoke unintended autoimmune attacks in the long run.
Are autoimmune diseases on the rise?
Autoimmune diseases as a group are definitely on the rise and becoming more common worldwide, especially in industrialized nations. For example:
- The incidence of type 1 diabetes increased by 2-5% worldwide each year between 1960 and 1996.
- The estimated U.S. prevalence of autoimmune disorders went from 3% in the 1960s to 7-9% in the 2000s.
- Up to 23.5 million Americans are estimated to suffer from autoimmune diseases, and the prevalence is increasing annually.
Researchers have proposed various explanations for the growth in autoimmune conditions:
- Increased hygiene and less exposure to microbes that educate the immune system.
- Greater exposure to chemicals, toxins, and irritants.
- Higher rates of obesity, which promotes systemic inflammation.
- An aging population more susceptible to autoimmunity.
- Improved diagnosis that catches milder cases.
But could the trend also be fueled by more people attempting to enhance their immunity through supplements, superfoods, and specialized diets?
Can boosting immunity trigger autoimmune disease?
Although global rates of autoimmune disorders are rising, there is no direct cause and effect evidence that boosting immunity causes autoimmune disease in otherwise healthy individuals.
However, research does suggest it’s plausible that inappropriate immune stimulation could trigger autoimmunity under the right circumstances. Some examples:
- The influenza vaccine may rarely exacerbate Guillain-Barre syndrome, an autoimmune nerve condition.
- Interferon therapy for hepatitis C infection is associated with development of autoimmune disorders like thyroiditis.
- Check point inhibitor drugs that hyper-stimulate T cells to attack cancer also often provoke autoimmune side effects.
So while immunity boosting alone probably won’t cause autoimmunity in most folks, it does appear capable of nudging the immune system to cross the threshold into self-attack in some cases.
Who is most at risk from immune over-activation?
Based on the available evidence, certain populations appear most vulnerable to having an overactive immune system turn against the body.
- Those with family history. If you have close relatives with autoimmune disorders, you likely share genetic risk factors.
- Women. Many autoimmune conditions disproportionately affect women, likely relating to hormonal influences on immunity.
- Middle age and older. Autoimmune disease risk increases with age as immune function declines.
- Previous infections. Past exposures to certain viruses and bacteria can predispose people to autoimmunity.
- Intestinal permeability. Those with a leaky gut may be more prone to immune over-activation against substances crossing into the blood.
People who fall into these higher risk categories may want to be cautious about overly stoking their immune defenses.
Tips for strengthening immunity safely
You can take steps to enhance your body’s natural defenses against disease without going overboard and potentially provoking autoimmunity.
Some safe ways to support your immune system include:
- Eating a balanced diet rich in fruits, vegetables, whole grains, and plant protein.
- Exercising regularly to reduce inflammation.
- Getting adequate sleep and managing stress.
- Avoiding smoking and excessive alcohol.
- Maintaining a healthy gut microbiome with prebiotics and probiotics.
- Trying immune-supporting herbs like elderberry, garlic, and green tea.
If you have autoimmune disease risk factors, take a personalized approach and consult your physician before attempting to boost immunity.
The bottom line
Having a strong and responsive immune system is vital for health. But efforts to artificially boost immunity can backfire in some people and promote autoimmune disease.
General immune stimulants as well as interventions that target specific immune components like antibodies or toll-like receptors could potentially trigger self-attack in those predisposed.
Rather than trying to directly enhance immunity, your best bet is adopting a balanced, healthy lifestyle that allows your immune system to function at its best.
If you have autoimmune disease risk factors, take a cautious approach to immune enhancement and speak with a doctor to determine what strategies are appropriate for you.