Jaundice, minus the panic

Medically-informed · Sources: MedlinePlus · Updated June 2026 · 3 min read

What you're seeing

A yellow tint to the skin and eyes shows up in most newborns — it's usually the single most googled thing in week two. The cause is bilirubin, a normal byproduct of replacing the extra red blood cells babies are born with. A brand-new liver simply needs a few days to catch up with the workload.

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The typical arc

Physiological jaundice commonly appears on day 2–3, peaks around days 3–5, and fades by the end of week two. It typically starts at the face and moves down the body as levels rise — which is exactly why the follow-the-yellow check matters more than the shade itself.

Is this normal for your baby?

FirstWeeks answers with your baby’s age and today’s log in mind — with pediatric sources attached.

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Feeding is the treatment

Bilirubin leaves the body through stool, which means the everyday fix is unglamorous: frequent feeds. Every feed is literally flushing the yellow out. If your baby is feeding 8–12 times a day and producing wet and dirty diapers on schedule, the system is working.

When it's a same-day call

Call your pediatrician today if the yellow spreads below the knees, deepens after day five, or comes with a sleepy baby who's hard to wake or feeding poorly. Yellow visible in the first 24 hours of life is always checked immediately. None of these calls are overreacting — bilirubin is measured with a quick painless test, and treatment (light therapy) is routine and effective.

What not to do

Sunlight through a window is not a treatment plan — it's unreliable and risks overheating. Sugar water isn't either. Feed, count diapers, watch the spread, and let the pediatrician own the numbers.

The honest summary

Jaundice is the most common newborn condition there is, and the overwhelming majority of cases resolve with nothing but time and milk. Your job isn't to fix it — it's to feed and to notice. Both are things you're already doing.