Learn how the hormone insulin regulates your blood sugar, why blood sugar levels matter, and side effects to watch for if you take prescription insulin.

The practice, in which users inject the blood of already intoxicated individuals, has fueled one of the fastest-growing H.I.V. epidemics in the Pacific and grown widespread in South Africa.

While President Donald Trump is pushing to split the MMR vaccine into three shots, experts say there’s no scientific reason for it, and it could lead to lower vaccination rates.

If you’re a needlepointer, you know that little thread scraps, called “orts”, accumulate faster than you can stitch. Rather than letting them scatter across your workspace, creating a designated ort ...