Beyond Discoloration – The Potential Health Impacts of Untreated Toenail Fungus Toenail fungus (onychomycosis) is a common condition affecting millions worldwide. While often dismissed as a mere aesthetic concern, neglecting this fungal infection can pose several potential health risks. This article will look beyond the discolored and thickened nails and explore the implications of untreated toenail fungus. Understanding the Enemy – Types and Progression of Toenail Fungus Fungi, microscopic organisms, thrive in warm, moist environments, making the toes prime targets. Three main types of fungi can cause toenail infections: Dermatophytes Yeasts Molds Initially, the infection usually manifests as a white or yellow spot under the tip of the toenail. As the fungus spreads, the nail may thicken, become brittle, and crumble at the edges. Discoloration, often ranging from yellow to brown, is also common. If you ignore this condition, the toenails