Ammonia is a toxic byproduct of protein metabolism. Typically, there is very little ammonia circulating because the liver detoxifies ammonia efficiently. However, this process can become impaired due to poor mitochondrial function, manganese or biotin deficiency or genetic predisposition. Elevated ammonia can result from any of these causes, as well as excessive protein intake, stress or liver issues. Ammonia is also produced by some pathogenic bacteria in the gut, which may be a contributor to high ammonia as well. High ammonia levels can cause cellular damage, which can contribute to symptoms like fatigue and brain fog.
 
Stress can be anything that interrupts the body's homeostasis. This could be physical, emotional, psychological, infectious, among countless other contributors to systemic stress. Stress manifests through several different hormones, signaling molecules, and other processes that have numerous consequences on health. Stress tends to suppress the immune system, deplete nutrients, disrupt organ function, break down tissue, impair metabolism and ultimately contribute to intlammation and oxidative stress. All of these can result in symptoms, from fatigue and brain fog, to digestive issues, impairments in metabolism, and more. Periodic stress is normal and even healthful, but chronic stress plays a pivotal role in nearly every health issue.