Biology Insights

Rheumatoid arthritis has no single cause. Genetics, smoking, infections, and hormones can combine to trigger the immune system to attack your joints.

At two weeks post knee replacement, here's what's normal for pain, swelling, mobility, and your incision — and what warning signs to watch for.

Period clots are usually normal, but size and color can signal conditions like fibroids or endometriosis. Here's what to watch for.

Canker sores are small, pale ulcers with a red border. Learn what they look like, where they form, and how to tell them apart from cold sores.

Accidentally took two doses of Trulicity? Here's what side effects to expect, how long they last, and when to seek medical help.

Bumps on the back of your head are usually folliculitis or clogged pores. Learn what causes them and how to treat them at home or with a doctor.

Breastfed babies can go days without pooping and still be perfectly healthy. Here's what's normal at each age and when to check in with your doctor.

Cystic pimples need a different approach than regular acne. Here's what actually works, from home remedies to cortisone shots and prescriptions.

Most tongue bumps are harmless, but knowing the difference helps you decide when to treat at home and when to see a doctor.

Find out how much walking you need to lose weight, with calorie charts by body weight, step-to-mile conversions, and a simple weekly plan to follow.

Daily Liquid IV has real trade-offs. Here's what the ingredients mean for your health and when it actually makes sense to use it.

Learn how type 2 diabetes affects your body, what symptoms to watch for, who's at risk, and how it's managed day to day.

The original Moderna and Pfizer COVID vaccines lost authorization because updated formulas replaced them. Here's what changed and what's available now.

Dogs typically have discharge for 3–4 weeks after giving birth. Learn what normal looks like, how it changes over time, and when to call your vet.

Alcohol detox typically takes 3–7 days, but the timeline varies. Learn what to expect during withdrawal and why medical supervision matters.

At 2 months pregnant, a lot is happening inside and out. Here's what your embryo, ultrasound, and body actually look like at this stage.

Home remedies like Vicks VapoRub can clear toenail fungus, but only if you use them consistently and prevent reinfection. Here's what actually works.

At 5 weeks pregnant, symptoms like nausea, fatigue, and cramping are common — but feeling nothing is normal too.