Table 3.

MDEVs influence various aspects of host health.

Host System	MDEV Effects	Potential Mechanisms	References
Gut–Brain Axis (IBD)	Disrupt gut barrier, worsen inflammation	Activate immune responses, disrupt barrier integrity, disrupt immune tolerance	[86,87]
Metabolic Health (Obesity)	Influence adipogenesis, insulin sensitivity, inflammation	Carry molecules affecting adipogenesis, etc., shape gut microbiota, trigger inflammation	[89,90]
Nervous System (Neurological Disorders)	Modulate neuroinflammation, neurotransmitter production	Modulate gut–brain axis signaling, influence SCFA levels	[91]
Behavior (Social Behavior)	Shape reproductive behavior, influence sociability	Horizontal transmission of gut microbiota, influence social behavior via metabolites	[92,93,94]