Although COVID-19 often attacks the lungs, it is increasingly associated with a range of problems including blood clots, neurological disorders, and kidney and heart damage. Researchers say new-onset diabetes may soon be added to those complications — both Type 1, in which people cannot make the insulin needed to regulate their blood sugar, and Type 2, in which they make too little insulin or become resistant to their insulin, causing their blood sugar levels to rise. But scientists do not know whether COVID-19 might hasten already developing problems or actually cause them — or both.