From the Guidelines

There is no direct evidence to suggest a relationship between mushroom consumption and autoimmune disorders.

The provided evidence discusses the relationship between diet, gut health, and autoimmune disorders, but does not specifically mention mushroom consumption 1.
A Mediterranean-style diet, which is rich in fruits, vegetables, and whole grains, has been linked to a lower risk of developing autoimmune disorders such as systemic lupus erythematosus (SLE) 1.
Diets high in processed foods, sweets, and saturated fats are associated with an increased risk of autoimmune disorders 1.
The gut microbiota plays a crucial role in immune system function and inflammation, and an imbalance of the gut microbiota has been linked to autoimmune disorders 1.
Certain dietary components, such as prebiotics and probiotics, have regulatory effects on inflammatory diseases and may help promote a healthy gut microbiota 1.

A balanced diet that is low in inflammatory foods and high in fruits, vegetables, and whole grains may help reduce the risk of autoimmune disorders.
The gut microbiota is essential for immune system function and inflammation, and an imbalance of the gut microbiota may contribute to autoimmune disorders.
More research is needed to determine the specific relationship between mushroom consumption and autoimmune disorders.

From the Research

The current evidence suggests that mushroom consumption may have an impact on immune function and potentially reduce the risk of autoimmune disorders 2, 3.
A study published in the Journal of the American College of Nutrition found that consuming Lentinula edodes (Shiitake) mushrooms daily improved human immunity in healthy young adults, with increased γδ-T cell proliferation and activation responses, and reduced inflammation 2.
Another study published in Food & Function found that mushroom consumption was associated with a lower risk of mild cognitive impairment in Chinese older adults, and that this association was mediated by inflammatory factors such as interleukin-6 (IL-6) and hypersensitive C-reactive protein (hs-CRP) 3.
However, the evidence is not yet conclusive, and more research is needed to fully understand the relationship between mushroom consumption and autoimmune disorders 4, 5.
The mechanisms by which mushrooms may affect immune function and autoimmune disorders are not yet fully understood, but may involve the modulation of immune cell activation and the reduction of inflammation 5, 2.

Mushrooms contain a range of bioactive compounds, including glucans, proteins, and phenols, which may have immunomodulatory and anti-inflammatory effects 5.
The specific compounds and mechanisms involved may vary depending on the type of mushroom and the individual's immune status 5, 2.
Further research is needed to fully elucidate the mechanisms by which mushrooms may affect immune function and autoimmune disorders 4, 5.

The current evidence is largely based on in vitro and animal studies, and more human trials are needed to confirm the effects of mushroom consumption on immune function and autoimmune disorders 4, 5.
The relationship between infectious agents and autoimmune diseases is complex, and more research is needed to understand the potential role of molecular mimicry in the development of autoimmune diseases 6.
Further studies should investigate the effects of different types of mushrooms and their bioactive compounds on immune function and autoimmune disorders in humans 5, 2.