We rarely think about sweat as anything more than a side effect of heat or exercise, but it may be more valuable than we realize. The drops our bodies naturally excrete contain a chemical fingerprint of what’s happening inside, including early warning signs of diseases such as diabetes, cancer, Parkinson’s, and Alzheimer’s that a doctor might not catch for years.
Sweat contains biomarkers, such as cortisol, hormone levels, electrolytes, glucose, and even medication levels that offer clues about everything from stress and metabolic health to how well a person is responding to treatment, according to a study published in the Journal of Pharmaceutical Analysis.
