ScienceInsights

How often you should do a nasal rinse depends on why you're using one. Here's what's safe for colds, allergies, post-surgery, and kids.

Learn how cold sores change in appearance from the first tingle to healing, and how to tell them apart from pimples or other lip issues.

Learn how to find your calorie target for weight loss, why food quality matters, and how to adjust your intake as your body changes over time.

Learn how the refractory period, sperm count, hormones, and overall health are affected by ejaculation frequency, and what's actually considered normal.

Grief after losing a spouse has no set timeline. Learn what the research says about waves of grief, the first year, and when to seek support.

From pelvic floor exercises to delay sprays, here's what actually works for lasting longer in bed — and what the research says about each option.

Most 5 year olds need 10–13 hours of sleep. Here's how to help them get it, handle disruptions, and build a routine that actually sticks.

Early cavities can sometimes be reversed through remineralization, but timing matters. Here's what actually works at home and when you need a dentist.

Weight loss timelines vary more than most guides admit. Here's what the science says about realistic rates, plateaus, and when you'll notice changes.

Stomach growling is your gut's cleaning cycle at work, not just a hunger signal. Here's what's actually happening and when to pay attention.