What is the optimal vitamin D level for women?

Your blood test reads 32 ng/mL — technically "within range." But your energy is flat, your cycle is unpredictable, and your hair is shedding more than it used to. The standard lab range for vitamin D was built to detect deficiency, not to optimize how women actually feel. The 30–100 ng/mL window is a 70-point spread, and where you sit inside it tends to matter more than simply being "normal." Most women report functioning best somewhere between 40 and 60 ng/mL — backed by observational evidence, not just functional-medicine talking points.