Chronic pain can rob you of sleep — and poor sleep can make pain feel even worse. Researchers say a familiar bedtime supplement may have an unexpected advantage: It appears to target both sides of that vicious cycle.

Pancreatic ductal adenocarcinoma is on the fast track to becoming the second-leading cause of cancer-related deaths. Why? A common denominator in two common conditions turns cells cancerous, but there’s a way to throw a kink into the equation…

Think summer sunshine is enough to rebuild your vitamin D stores? New research suggests that for many people the “sunshine vitamin” may stay low all year long. And that could matter more with every passing birthday.

Most people expect pain after surgery. But one common vitamin deficiency could make that pain worse — leaving patients in need of more opioid medication to get through recovery. That’s not surprising once you know this vitamin’s pain-relieving links…

After years of mixed findings, a new meta-analysis may explain why vitamin D helps depression symptoms in some studies but not others: Like with medicine, dosage matters…

Chemotherapy is a standard tool used against breast cancer, but researchers are always looking for ways to help it work better. A small clinical trial points to an inexpensive vitamin that may help more women see a more “complete” response…