Hello Research Enthusiasts!
The Research Dose is designed for both quick reads and deeper dives. Each issue begins with a brief overview and key takeaways for readers who want the essentials fast. From there, we break down the study design, methods, limitations, and findings in greater detail—so you can understand not just the results, but the context behind them.
Study Introduction
Introduction
Autoimmune diseases (AiD) are chronic conditions where the body’s defense system mistakenly attacks its own healthy cells. In the U.S. alone, at least 15 million people are living with a diagnosed autoimmune condition, but experts believe the actual number is much higher due to underdiagnosis and a lack of centralized tracking. Global rates are rising steadily, making it a critical public health priority to understand why our immune systems are increasingly turning inward.
Mechanisms of enviornmental risk factors for autimmune diseases
Maruvada A and Miller FW. Autoimmunity Reviews, March 2, 2026
Disclosures: This research was supported by the Intramural Research Program of the NIH, specifically the National Institute of Environmental Health Sciences (NIEHS). The authors declared no financial conflicts of interest. Interestingly, they noted that a generative AI tool (ChatGPT) was used specifically to help organize and format their extensive reference list, though the researchers verified and edited all content for accuracy.
What can we learn from this research?
Key Takeaways
Summary
While genetics play a role, this study highlights that environmental factors contribute more than twice as much as genes to the development of autoimmune diseases. The researchers explored how "triggers"—everything from wildfire smoke and household chemicals to chronic stress and lack of sleep—physically change our biology. These triggers can damage our DNA, alter protein structures, and break down the "walls" (like the gut barrier) that keep harmful substances out of our bloodstream. These changes essentially "trick" the immune system into failing to recognize the body’s own tissues, leading to chronic inflammation and disease.
Real-Life Impact: What This Means for You
The big takeaway is that your environment matters. Because environmental factors are often modifiable, this research opens the door to proactive prevention.
Understanding that things like UV exposure, tobacco smoke, and even high-stress lifestyles are active "architects" of disease means we can advocate for cleaner environments and better personal habits.
For those already diagnosed, identifying specific triggers can lead to personalized treatment plans that go beyond just managing symptoms to addressing the external factors making the disease worse.
Quick readers can stop here. For the deep divers, let’s unpack the study further.
Here Comes The Detail…
Research Aim
The primary goal of this study was to provide a comprehensive overview of the pathways through which environmental risk factors might interact with our genetics to trigger autoimmune diseases, while also identifying unresolved knowledge gaps in the field.[1]
Study Design
This was a scoping review, which is a type of study designed to map the existing literature on a broad topic to identify key concepts, evidence types, and gaps in research. This review type is very similar to a systematic review, in that it utilizes a systematic search approach, but it does not assess the methodological quality of the included studies.
Study Methods
The researchers conducted an extensive literature search using NIH and PubMed databases for articles published between 1985 and 2025. They used approximately 122 specific search terms to identify the diseases included in the National Academies of Sciences, Engineering, and Medicine (NASEM) review.[2] This search yielded 1,010 original research articles and 589 review articles (published between 2015 and 2025). The team also searched book databases and used reference management software to categorize findings by proposed biological mechanisms.[2]
Study Highlights
Genetic vs. Environment: Data suggests that environmental contributions to AiD are generally twice as high as genetic contributions.[1]
DNA Damage: Ionizing radiation (from medical treatments or disasters) and UV radiation can cause oxidative stress, leading to DNA damage that triggers immune activation, particularly in thyroid diseases like Graves'.[3]
Epigenetic Shifts: Pollutants like bisphenol A (BPA) and heavy metals can "turn on" or "turn off" genes without changing the DNA sequence, increasing susceptibility to Lupus (SLE) and Rheumatoid Arthritis (RA).[4]
Protein Modifications: Factors like tobacco smoking can trigger an enzyme process called citrullination, which modifies proteins in the lungs and joints so the immune system sees them as foreign invaders.[5]
The Gender Gap: Estrogen can influence how immune cells respond to self-tissue, explaining why females are significantly more likely to develop conditions like Graves' disease or SLE.[6]
Barrier Disruption: A "leaky" gut or damaged lung lining (from silica or smoke) allows proteins like gluten to enter the bloodstream, triggering immune responses in genetically predisposed individuals.[7]
Molecular Mimicry: Certain infections, such as Epstein-Barr Virus (EBV) or SARS-CoV-2, have proteins that look like human proteins, causing the immune system to accidentally attack the body while trying to fight the virus.[8]
Strengths
The study is exceptionally broad, synthesizing decades of research into a unified framework of initial and secondary mechanistic pathways.
It successfully bridges the gap between different fields—such as toxicology, endocrinology, and immunology—to show how they intersect in autoimmune pathology.
Limitations
A major challenge noted by the authors is the difficulty in distinguishing between association and direct causation.[9] Because many autoimmune diseases take years to develop, it is hard to prove that a specific exposure decades ago caused a current diagnosis.
Additionally, the study notes that most research looks at single exposures rather than the reality of "mixtures"—how being exposed to smoke, stress, and chemicals all at once affects the body.[10]
What We Still Don't Know
There is a massive need for longitudinal "exposome" studies that track an individual's total environmental exposures from birth through adulthood.[11]
We still don't fully understand the synergistic effects of chemical mixtures or the exact timing of susceptibility—for instance, why some exposures are more dangerous during puberty or pregnancy than at other times.[10]
Finally, the long-term impact of climate change—such as increased wildfire smoke and extreme weather events—on the global rise of autoimmunity remains a critical, unanswered question.[12]
Transparency is key, especially when it comes to evidence-based research! Bolded numbers correspond to where the references appear in the study examined in this newsletter.
References
#6: Bogdanos DP, Smyk DS, Rigopoulou EI, et al. Twin studies in autoimmune disease: genetics, gender and environment. J Autoimmun, 2012.
#9: Committee for the Assessment of NIH Research on Autoimmune Diseases. Enhancing NIH research on autoimmune disease. National Academies Press, 2022.
#14: Lumniczky K, Impens N, Armengol G, et al. Low dose ionizing radiation effects on the immune system. Environ Int, 2021.
#23: Kundakovic M, Champagne FA. Epigenetic perspective on the developmental effects of bisphenol A. Brain Behav Immun, 2011.
#52: Makrygiannakis D, Hermansson M, Ulfgren A-K, et al. Smoking increases peptidylarginine deiminase 2 enzyme expression in human lungs and increases citrullination in BAL cells. Ann Rheum Dis, 2008.
#81: Forsyth KS, Jiwrajka N, Lovell CD, et al. The conneXion between sex and immune responses. Nat Rev Immunol, 2024.
#99: Martina S, Fabiola F, Federica G, et al. Genetic susceptibilty and celiac disease: what role do HLA haplotypes play? Acta Biomed, 2018.
#119: Cusick MF, Libbey JE, Fujinami RS. Molecular mimicry as a mechanism of autoimmune disease. Clin Rev Allergy Immunol, 2012.
#157: Schmidt CW. Questions Persist: Environmental factors in autoimmune disease. Environ Health Perspect, 2011.
#141: Nunez SG, Rabelo SP, Subotic N, et al. Chronic stress and autoimmunity: the role of HPA axis and cortisol dysregulation. Int J Mol Sci, 2025.
#165: Vojdani A, Vojdani E, Rosenberg AZ, et al. The role of exposomes in the pathophysiology of autoimmune diseases II: pathogens. Pathophysiology, 2022.
#2: Miller FW. Environment, lifestyles, and climate change: the many nongenetic contributors to the long and winding road to autoimmune diseases. Arthritis Care Res, 2025.
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That concludes this segment of The Research Dose! If you have a particular study or area of interest you would like me to dive into next, feel free to let me know!
Until the next dose,
EC
Disclaimer: This content is for informational and educational purposes only. It does not constitute a medical opinion, medical advice, diagnosis, or treatment of any particular condition. Always seek the advice of your physician, mental-health professional, or other qualified health provider with any questions you may have regarding a medical condition.