Maybe - two 2010 trials (same authors) investigating marine collagen peptides on glucose metabolism in 200 Chinese adults (one study on patients with type 2 diabetes and taking diabetes medications and the other study on patients with type 2 diabetes and hypertension on medications) found that, 13 g of marine collagen peptides per day for three months reduced fasting blood glucose by 1.5 to 2.0 mmol/L and HgbA1C by 0.75%. Results may be limited by the small sample sizes, short study durations and the lack of generalizability beyond Chinese adults aged 60 to 70 years with type 2 diabetes and on medications.