Chronic microinflammation is a hallmark of many aging-related neurodegenerative diseases as well as metabolic syndrome-driven diseases. Recent research indicates that chronic caloric excess can lead to hypothalamic microinflammation, which in turn participates in the development and progression of metabolic syndrome disorders such as obesity, glucose intolerance, and hypertension. Additionally, it was recently shown that increasing age after young adulthood can cause hypothalamic microinflammation independently of nutritional status, mediating a central mechanism of systemic aging. Taken together, these findings suggest that the hypothalamus has a fundamental role, via hypothalamic microinflammation, in translating overnutrition and aging into complex outcomes. Here we summarize recent work and suggest a conceptual model in which hypothalamic microinflammation is a common mediator of metabolic syndrome and aging.