Mushrooms, particularly certain medicinal varieties such as Hericium erinaceus (Lion’s Mane), Reishi (Ganoderma lucidum), and Cordyceps, have been explored in scientific research for their potential effects on mood and mental health. Studies suggest that some of these mushrooms contain bioactive compounds, such as hericenones, erinacines, and polysaccharides, which may influence neurotrophic factors, modulate neuroinflammation, and support overall brain health. For example, small-scale clinical trials and animal studies have reported that Lion's Mane supplementation may reduce symptoms of depression and anxiety, which can contribute to mood stability.

However, the evidence specifically supporting the use of mushrooms for "mood swings"—as seen in conditions like bipolar disorder or premenstrual syndrome—is limited and of low quality. Most studies focus on general mood, anxiety, or depressive symptoms rather than cycling mood states. While traditional use of certain mushrooms for well-being exists, the modern scientific validation is preliminary, with most studies being small, short-term, and often lacking rigorous controls. No major clinical guidelines currently recommend mushrooms as a primary treatment for mood swings.

In summary, while there is emerging scientific interest and some early evidence that certain mushrooms may benefit general mood, the support for their use in treating mood swings is weak, and more high-quality research is needed.