When did the Nazi human experiments start?

Nazi human experiments began shortly after Adolf Hitler came to power in 1933, but they escalated significantly during World War II, particularly from 1939 to 1945. These experiments were conducted in concentration camps, with notorious examples including those at Auschwitz, Dachau, and Buchenwald. The studies often involved inhumane treatments, including medical experiments on prisoners, aimed at advancing military and racial ideology. Such atrocities were officially sanctioned by the Nazi regime and continued until the end of the war in 1945.