What ah ma got right about your child's eyes
Grandmothers get blamed a lot in my clinic. Several of the things ah ma has been saying for forty years turn out to be right, and one of the wrong ones is worth correcting properly.
- Go and play outside is the best-supported piece of folk advice about children's eyes, with two school trials behind it.
- Sharing towels and pillows really does pass on the sticky and gritty kinds of conjunctivitis. The allergic kind is not contagious at all.
- Reading in dim light does not damage eyes. Good light still helps, because it makes reading more comfortable and delays tiring.
- Carrots are half right. Vitamin A is needed for vision, but extra will not sharpen sight beyond normal or keep a child out of glasses.
- The one belief worth correcting is that a child will grow out of a turning or drifting eye. A real squint does not settle on its own.
Somewhere between the clinic door and the chair, a grandmother usually gets blamed. She feeds him too many sweets, she lets him watch the tablet, she says he will grow out of it. I hear the apology before I hear the symptom.
So let me put a word in for ah ma. Several of the things she has been saying for forty years turn out to be right, and right for reasons nobody in her generation was ever given. A few of them are wrong. One of the wrong ones does real damage, and it is worth knowing which, so that the family argument can move on to something more interesting.
Which of the old sayings should I actually listen to?
Three of them. Send the child outside. Do not share towels or pillows when someone has sore eyes. And read in decent light, not because dim light damages anything but because good light is more comfortable. Those three hold up.
The rest of this article takes them one at a time, then deals fairly with the ones that do not hold up, including the single most expensive sentence in Malaysian paediatric eye care. None of it is a reason to correct your mother in law at dinner. It is a reason to know which advice to follow when the two of you disagree.
Is there really anything in "go and play outside"?
Yes, and it is the best-supported piece of folk advice on the list. Two school trials added outdoor time to the school day and both found less short-sightedness afterwards. This is the one where ah ma is not merely tolerable but ahead of the evidence.
In Guangzhou, six primary schools added one extra forty-minute outdoor class each day for grade one children and encouraged families to keep it up after school, while six schools carried on as normal. Just over nineteen hundred children, three years. Short-sightedness developed in about 30 per cent of the outdoor group and about 40 per cent of the others, a gap of nine percentage points. In Taiwan, sixteen schools encouraged children to be outdoors up to eleven hours a week; those children shifted less towards short-sightedness and their eyes grew less than the children in the schools that carried on as usual.
Two honest limits. Both trials worked with children just starting school, and what they tested was whether short-sightedness started, which is a different question from whether outdoor time helps a child who is already short-sighted. And nobody has established the exact dose. The outdoor time question, sized properly sets out what the numbers do and do not support, so I will not re-argue it here. What ah ma got right is the direction. Outdoors is better than indoors for young eyes, and that is not folklore any more.
Can she really catch sore eyes from sharing a towel?
Yes, depending on which kind of sore eye it is. Conjunctivitis that produces sticky pus is contagious, and red gritty eyes usually are too. The allergic kind, red and watery from dust or pollen, is not contagious at all and never was.
So the household rules ah ma imposes when one child wakes up gummed shut are the correct rules. Wash hands often with warm soapy water. Wash pillowcases and face cloths in hot water and detergent. Do not share towels and pillows. That is close to word for word what the health advice says, and it is the whole of the containment strategy in an ordinary house.
She is also right about the cold flannel. Holding a cool cloth over closed eyes for a few minutes settles them, and it is the first thing I suggest too. Where I would part company with the old approach is anything else applied to the eye, which I come back to at the end. If you are trying to work out which kind of red eye you are dealing with, pink eye in children sorts the sticky from the watery from the itchy.
Will reading in dim light ruin his eyes?
No. Reading in dim light does not harm the eyes, and neither does close detail work. Eyes are not worn out by being used, which is the assumption sitting underneath most of this particular worry.
But do not dismiss her too fast, because the practical half of the advice is sound. Good light makes reading easier and delays tiring, so a child reading in a gloomy corner will get uncomfortable sooner and give up sooner. Turn the lamp on for comfort and concentration. Just do not tell him his eyes will be spoiled, because that is the part that is not true, and children remember the threat long after they forget the reason.
The same distinction rescues her other favourite, sitting too close to the television. That does not damage eyes either. It can, though, be a sign that the far end of the room is blurry, which makes it worth an eye test rather than a scolding.
Ah ma keeps feeding him carrots. Does it work?
Partly, and less than she hopes. Vitamin A genuinely is needed for healthy vision, which is why the belief exists. But the body needs only a relatively small amount of it, and eating extra vitamin A rich foods will not sharpen a child's sight beyond normal or keep him out of glasses.
Carrots are not the only source either. Dark leafy greens, brightly coloured vegetables, dairy and fish all supply it, so a child who refuses carrots is not being deprived of anything. Nobody eats their way to better than normal vision, in the same way that nobody eats their way to being taller than they were going to be.
My honest position is that this myth is harmless and I let it run. A grandmother who has persuaded a four-year-old to eat vegetables has achieved something I certainly could not, and the reasoning being slightly off does not spoil the result.
Which one should I gently let go of?
"Never mind, he will grow out of it," said about an eye that turns or an eye that drifts. That is the one that costs children sight, and it is the only belief on this list I will argue about.
A squint is unlikely to get better on its own, and vision problems may be permanent if they are not treated while a child is young. The confusion is understandable, because there is a lookalike that genuinely does settle: a baby with a wide nasal bridge can look cross-eyed while the eyes are perfectly straight, and that appearance does resolve. A real squint does not. Only an examination tells you which one is in front of you, which is exactly the argument of crossed eyes in newborns, and how to spot a lazy eye early covers the drift that hides behind the same sentence.
Two smaller ones can go at the same time. Glasses do not weaken a child's eyes or make them dependent, and skipping prescribed glasses is what actually harms developing vision. And a child who crosses his eyes to make you laugh will not get stuck that way. The full myth list, sorted takes the rest of them.
What about the remedies she wants to put in his eye?
Those are where I stop nodding. Breast milk, herbal water, warmed oil, a rinse of something home-brewed: an eye is not a wound on the skin, and anything unsterile going onto an already irritated surface can turn a nuisance into an infection.
Breast milk in a sticky eye is the one I am asked about most in Malaysia, and it deserves a straight answer rather than an eye roll, so what the evidence actually says about it has its own piece. The short version is that the confidence around this remedy is much larger than the evidence for it.
Here is how I would leave the whole conversation. Ah ma got the outdoors right, the towels right, and the reading lamp right for the wrong reason. She got the carrots half right and it does no harm. The only thing worth correcting is "he will grow out of it", and the correction is not an argument, it is an appointment. Bring her along to it if you like. In my experience she asks better questions than anyone.
- One eye turns in or out constantly at any age, or comes and goes past three to four months.
- Your child sits very close to the screen, holds books close, or squints at the far side of the room.
- Anyone suggests waiting because a turning eye will be outgrown.
- A sticky or gritty red eye is not settling after a few days of ordinary hygiene at home.
- Anything other than a clean cool cloth or prescribed drops is being put in your child's eye.
Common questions
My mother says reading in the dark will ruin his eyes. Is that true?
Is there anything to the old advice about playing outside?
Can my child catch sore eyes from sharing a towel?
Ah ma keeps feeding him carrots for his eyesight. Does it work?
Will my child grow out of a turning eye?
Do glasses make a child's eyes weaker?
Is it safe to put breast milk or a herbal rinse in a sticky eye?
- American Academy of Ophthalmology · Common eye myths and facts · www.aao.org
- Effect of time spent outdoors at school on the development of myopia among children in China, a randomised clinical trial, JAMA 2015 · pubmed.ncbi.nlm.nih.gov
- Myopia prevention and outdoor light intensity in a school-based cluster randomised trial, Ophthalmology 2018 · pubmed.ncbi.nlm.nih.gov
- NHS · Conjunctivitis · www.nhs.uk
- AAPOS · Glasses for children · aapos.org
- American Academy of Ophthalmology · Strabismus in children · www.aao.org
- NHS · Squint · www.nhs.uk
- American Academy of Ophthalmology · Can close TV viewing damage eyes? · www.aao.org