Crocus Sativus Tepals Water Extract in Obesity and Prediabetes

The goal of this clinical trial is to determine the acute effects of ingestion of a cold aqueous extract of Crocus sativus tepals on postprandial glycemia and other indicators of metabolic health in patients with obesity and/or prediabetes. The main questions it aims to answer are: * Does the ingestion of Crocus sativus tepals cold aqueous extract prior to a meal improve the glycemic response to a standard meal? * How does the ingestion of Crocus sativus tepals aqueous extract prior to a meal impact insulin levels and other markers of metabolic health? * Does the ingestion of Crocus sativus tepals cold aqueous extract prior to a meal increase the resting energy expanditure? Researchers will compare Crocus sativus tepals cold aqueous extract to cold water. The participants will visit the Faculty twice - on one visit they will ingest Crocus sativus tepals cold aqueous extract and on the other cold water (in random order) 5 minutes prior to a standard meal of 100 g of white bread. On each visit, anthropometric measurements will be performed upon arrival. Blood samples will be collected 3 times, preceeded by resting metabolic rate and blood pressure measurements: at baseline in fasted conditions, and 60 minutes and 120 minutes after consuming the bread. There will be an at least 7 days wash-out period between the two visits.