A 2015 study by the Federal University of Rio Grande do Sul, Porto Alegre and the Regional University of Northwestern Rio Grande do Sul State, Brazil concluded that, “Heat therapy is a promising and inexpensive tool for the treatment of obesity and diabetes. … We suggest that heat therapy (sauna: 80–1008C; hot tub: at 408C) for 15 min, three times a week, for 3 months, is a safe method to test its efficiency.”
Heat Shock Protein 70 (HSP70) appears to play a part in improving “…insulin signaling, body composition, endothelial dysfunction, and the low-grade inflammation found in people with diabetes.”