Jemur baby, the habit of laying a yellow newborn in the morning sun, is not a jaundice treatment. The Ministry of Health’s own hospital handbook, the Paediatric Protocols for Malaysian Hospitals (2025), says sunlight to reduce jaundice “should be avoided due to risk of dehydration and sunburn”, and the American Academy of Pediatrics says sunlight is not a safe way to treat it. If your baby looks yellow, the fix is a bilirubin test at the klinik or hospital, and phototherapy if the number calls for it.
For vitamin D, the sun isn’t the plan before 6 months either; international guidance uses drops, and your doctor decides whether your baby needs them. What daylight is good for is setting your baby’s body clock, and that works fine in the shade.
Why jemur baby is still so common in Malaysia
Almost everyone’s mother or mother-in-law has suggested it. In a study of 400 mothers at Hospital Tuanku Jaafar in Seremban (published 2011), 83.1% of the 154 mothers whose earlier babies had jaundice had sunned them. Of those, about half laid the baby naked near a window but out of direct sun, 36.7% put the baby naked directly under the sun, and 11.7% put a fully dressed baby in the sun. Only 27.1% of all the mothers knew that sunning a jaundiced baby can cause dehydration and make jaundice worse.
The instinct isn’t silly. Hospital phototherapy works with blue light, and sunlight contains blue light. But sunlight also brings heat and ultraviolet, the dose is impossible to control, and you can’t see whether it’s working. Worse, it feels like doing something, so the baby who needs a blood test gets another morning at the window instead.
Does sunlight actually lower bilirubin? What the evidence says
A 2021 Cochrane review pulled together three trials covering 1,103 babies from two countries. In the trials that compared sunlight with phototherapy, the sun came through light-filtering tents that blocked ultraviolet and infrared radiation. The findings:
- Filtered sunlight brought bilirubin down at a similar rate to phototherapy, assuming at least four hours of sun a day with machine phototherapy at night when needed. Certainty was low.
- Filtered sunlight raised the risk of overheating (above 37.5°C): roughly one extra baby in three got too hot. The authors say frequent temperature checks may be needed.
- One prevention trial, with two 30-60 minute sun sessions a day, suggested less jaundice, but the evidence was very low certainty and readmissions for jaundice didn’t differ.
- The authors concluded that sunlight may be a useful add-on to phototherapy in low- and middle-income countries short of machines, and that the studies “have not demonstrated that sunlight alone is effective”.
That is a long way from a baby in a nappy on a Klang Valley balcony at 11am, with no UV filter, no temperature checks and no bilirubin test.
Hospital phototherapy is tightly specified. The MOH protocols call for blue light at around 475 nm, a measured minimum intensity, the lamp no more than 30-50 cm from the baby, eyes covered, temperature and hydration checked, and breastfeeding continued. Once a baby is under phototherapy, the protocols say judging colour by eye is unreliable and blood levels must guide treatment.
How to check for jaundice at home
Yellow spreads from head to toe as bilirubin rises. The MOH protocols use this guide, called Kramer’s rule:
| Where the yellow has reached | Rough serum bilirubin (µmol/L) | What to do |
|---|---|---|
| Head and neck | 68-133 | Mention it at your next check; keep looking daily |
| Chest and upper tummy, above the belly button | 85-204 | Get a bilirubin check soon, especially in the first week |
| Below the belly button and thighs | 136-272 | Get a check the same day; MOH protocols list this as a reason for hospital referral |
| Arms and lower legs | 187-306 | Get a check the same day |
| Palms and soles | 306 and above | Go to hospital urgently; the protocols call this a sign of severe jaundice |
Any yellow in the first 24 hours means hospital, whatever the zone. The ranges overlap and are only a rough guide; a blood or skin-meter test gives the real number. Look in daylight by the window, not under yellow ceiling lights. Yellow is harder to see on darker skin, so the NHS suggests pressing gently on the tip of the nose or forehead and checking the whites of the eyes and under the tongue.
Danger signs: when jaundice can’t wait
Most newborn jaundice is harmless and gone within 7 to 10 days. A small number of babies get bilirubin high enough to damage the brain and hearing, and the earlier it’s caught, the easier it is to bring down.
G6PD deficiency: the Malaysian factor
Malaysia screens every newborn for G6PD deficiency, and the protocols say the result should be reviewed within 24 hours. Yet in the Seremban study fewer than 20% of mothers knew what G6PD deficiency was. Babies with it break down red blood cells more easily, which can push bilirubin up fast.
The protocols say G6PD-deficient babies should be kept in and watched for jaundice for the first five days. Term babies over 2.5 kg can go home on day four if their bilirubin is below a set level and follow-up is close. If you’re asked to stay, that’s why.
What to avoid at home if your baby is G6PD deficient:
- Mothballs (kapur barus). Check the pack. The MOH protocols say naphthalene, one of the common moth repellent ingredients, can be absorbed through the skin or breathed in, and it causes haemolysis more readily in newborns and people with G6PD deficiency. Keep moth repellents out of the baby’s clothes, cupboard and room, and air out anything that has been stored with them.
- Henna, herbal remedies and fava beans. The AAP advises avoiding these for any newborn because in rare cases they can cause severe jaundice, and the MOH protocols say traditional and alternative medicines are not encouraged for jaundiced babies. That covers confinement herbal baths and pantang tonics: ask your doctor before using any on the baby, and check anything the mother takes if she’s breastfeeding.
- Some medicines. Tell every doctor and pharmacist that your child is G6PD deficient.
Feeding: the jaundice step you actually control
MOH protocols list lactation failure as a risk factor for significant jaundice and explain that poor breastfeeding slows the clearing of bilirubin. The AAP recommends breastfeeding at least 8 to 12 times a day in the first few days.
If latching hurts, your baby is sleepy at the breast, or nappies are drying up, ask for a lactation consultant or the klinik nurse now. Don’t wait for the yellow to fade. Breast milk jaundice, the gentle kind that can linger for weeks, isn’t a reason to stop breastfeeding; the protocols recommend continuing.
Jemur for vitamin D, or vitamin D drops?
The other reason grandparents give is “for the bones”. The body does make vitamin D from direct sun on skin outdoors. But babies under 6 months shouldn’t be in direct sun, and the window session doesn’t deliver much: window glass filters out UVB but lets UVA through. Your baby gets the heat and some UVA, and little of what you were hoping for.
The AAP, CDC and NHS all recommend a daily vitamin D supplement for breastfed and partly breastfed babies from the first days of life. Babies on enough formula don’t need one, because formula is already fortified.
The MOH hospital protocols spell out vitamin D drops only for premature babies. We couldn’t find a universal MOH instruction for healthy, full-term breastfed babies, so ask at the one-week or one-month check whether your baby should take vitamin D drops, which product and how much. Don’t double up on several multivitamin products without checking.
Morning light, the body clock and safe sun
Here’s the part of jemur worth keeping. Newborns don’t know day from night yet, and daylight helps teach them. The NHS suggests opening curtains and playing during the day, and keeping lights low at night. None of this needs sun on the skin:
- Do the morning feeds and play in your brightest room, next to the window but out of the patch of direct sun.
- Take a short walk before 9am under a covered walkway, trees or the stroller canopy.
- At night, keep it dark and boring. A cordless blackout blind also helps with daytime naps, and our baby sleep hub covers the rest of the night routine.
For sun safety under 6 months, the AAP says shade, cool covering clothes, and limited time outside between 10am and 4pm. Sunscreen is only for small areas such as the face when shade and clothing aren’t possible; pick zinc oxide or titanium dioxide. The WHO says to avoid being outside around midday when the UV index is 8 or above, which Malaysian middays regularly reach, cloud or not. Our sunlight hub covers light, UV and outdoor time as your baby grows.
From 6 months, add sunscreen (SPF 15-50, reapplied every 2 hours and after swimming), a hat with an all-round brim, and UPF clothing for anything longer than a quick walk. A suit like Decathlon’s Kloupi UV wetsuit covers arms, torso and legs, so less skin needs sunscreen. Our baby swimwear guide compares UPF suits for condo pools, and our post on when babies can start swimming lessons covers ages.
What this looks like in a Malaysian week
Say your baby is born on a Monday at a government hospital, G6PD normal, and you go home on Tuesday afternoon.
- Wednesday: The visiting nurse or klinik kesihatan sees your baby within 24 hours of discharge. The face is a little yellow; a skin-meter reading is below the treatment line, and you get a date to come back.
- Thursday and Friday: You feed 8 to 12 times a day, count wet and dirty nappies, and check colour by the window each morning. Your mother suggests jemur; you take a shaded stroll at 8am instead.
- Saturday: The yellow is below the belly button and your baby is sleepier at feeds. You don’t wait for Monday. At the hospital, a blood test shows a level that needs phototherapy, and breastfeeding continues under the lights.
- The following week: A follow-up check confirms bilirubin is falling. Mornings mean open curtains and shaded walks; nights mean a dark, cool room (our TOG chart for aircond rooms covers what to dress them in).
If your baby were G6PD deficient, you’d stay in for about five days while the team watched for jaundice.