Compositions including metabolites that are small molecules, and salts and derivatives thereof, and methods for treatment or prophylaxis of conditions related to the quality of aging are provided, including compositions and methods for treating conditions that negatively impact longevity and the quality of aging, including inflammation, anemia, hyperglycemia, dyslipidemia, hyperinsulinemia, liver disease, iron overload, impaired skin integrity, wound healing, scarring, pain, allergies, sleep disorders and problems, and gastrointestinal disorders and problems.