Type 2 Diabetes and Blood Brain Barrier Improvement

This study is investigating whether a vitamin called thiamine (vitamin B1) can help improve the blood-brain barrier in people with type 2 diabetes. A leaky blood-brain barrier may contribute to brain complications in people with diabetes. Researchers will use imaging to see if thiamine supplementation makes a difference. **You may be eligible if:** - You have been diagnosed with type 2 diabetes - You are treated as an outpatient (not hospitalized) - You are able to lie flat for imaging scans **You may NOT be eligible if:** - You have a history of stroke - You currently take thiamine supplements - You have a known allergy to thiamine - You have a seizure disorder, history of significant head trauma, or heart attack - You are currently pregnant - You have been diagnosed with depression, schizophrenia, or bipolar disorder - You have dementia or sleep-disordered breathing - You have chronic lung diseases such as COPD or cystic fibrosis - You have a brain tumor - You have a history of drug abuse - You have kidney failure requiring dialysis - You have metallic or electronic implants incompatible with imaging Talk to your doctor to see if this trial is right for you.