Wrist Photoplethysmography Predicts Dietary Information

This headline suggests a research finding where data collected from wrist-worn devices (photoplethysmography) can be used to infer information about a person's diet. The use of 'predicts' implies a predictive model is involved, likely using machine learning to analyze the PPG data and correlate it with dietary habits. The source, ArXiv, indicates this is likely a pre-print or research paper.