Picture this: deep in your gastrointestinal tract, there is a bustling metropolis of microscopic life. Bacteria, archaea, and fungi, all going about their business. We have known for a while that these tiny tenants help with digestion and support our immune system. They also make neurotransmitters, like serotonin. But scientists have discovered something truly mind-blowing - these microbes are miniature vitamin factories. If we nourish them, could they produce more vitamins and replace supplements?

Fish oil studies reveal a rift in the science around the pros and cons of omega-3 fatty acids, raising questions about how much a person should take—if any.

A recent study published in BMJ Medicine suggests that ingesting these oily little pills may contribute to atrial fibrillation and stroke.

However, an analysis of the collective research suggests that the seeming contradiction in the science is more likely reflecting the fact that people are different and what may harm some may help others.