BABY

Elisabeth Leiss McKellar doesn’t mince words: “I believe babies were intended to be breastfed, and if there was supposed to be more vitamin D in breastmilk, then it would be there.” She sees her one-year-old son, Joerg, as being low-risk for vitamin D deficiency. “He’s very fair-skinned, like me, and we are outside frequently,” she explains.

It’s hard to think of a vitamin as something controversial, but there are clearly two schools of thought about this one. McKellar has listened to the arguments on both sides and decided not to follow the current recommendation of the Canadian Paediatric Society that exclusively breastfed babies should be given a vitamin D supplement every day.

Both sides agree that vitamin D is important: When babies don’t have enough, they can develop rickets - a condition where the bones become soft and weak. And although it’s a vitamin, it’s not easily obtained from food. Our bodies manufacture vitamin D when sunlight shines on our skin. Mothers who get enough will pass on a supply to their babies during pregnancy. Rickets was first noted as a public health problem during the Industrial Revolution in Britain, when many people lived in cities where the skies were permanently darkened with smog. One solution was to add vitamin D to dairy products.

That remedy is still in effect: The milk you buy in the grocery store is fortified with vitamin D. However, some recent studies in the US and Canada found cases of rickets in breastfed babies, and this research led to the

CPS recommendation that all breastfed babies receive supplements until they are old enough to drink fortified cow’s milk. (Formula has vitamin D added.) This recommendation has been criticized by some breastfeeding advocates.

“In the cases where babies developed rickets, they had easily identifiable risk factors: dark skin and [mothers] wearing veils or other coverings so that there was no exposure to the sun,” argues Elisabeth Sterken, national director of INFACT Canada, a breastfeeding advocacy group. These babies are in a higher-risk group because dark skin hinders absorption of sunlight, and veils worn by their mothers during pregnancy would also lower the amount of vitamin D passed on to their infants. “I think this suggests vitamin D supplements could be used as an intervention when needed, not routinely,” says Sterken.

Toronto paediatrician and breastfeeding specialist Jack Newman suggests a case-by-case approach. “The highest risk situation would be a mother who is veiled, dark-skinned, doesn’t drink milk and doesn’t go outside,” he says. “If her baby doesn’t get exposure to sunlight either, then that baby should get vitamin D supplements.”

On the other hand, mothers like McKellar are at “virtually no risk,”

Newman says. “If the mother is light-skinned, spends a short time outside with some skin exposed [without sunscreen] - even if it’s just her face and hands - and consumes vitamin-D-fortified dairy products, she’ll have passed lots of vitamin D on to her baby during the pregnancy. If that baby also spends time outdoors, he’ll be fine.”

If a mother has not had enough sun exposure or vitamin D during her pregnancy, says Sterken, this should be addressed. “By simply treating all babies after birth, we ignore the issue of the mother’s nutritional status, and I think we should be paying attention to that as well.”

As a baby grows, his supply of vitamin D is gradually used up, but can be replenished when the sun shines on his skin. What about the concerns of exposing unprotected baby skin to the sun’s rays? “We’re not talking a long time in the sun,” explains Newman. Denis Leduc, chair of the community paediatric committee of the CPS, agrees that the amount of sunshine needed is small. “You need about six to ten percent of the skin exposed, for five to ten minutes, three or four days a week.” However, depending on your situation - your pigmentation and the strength of the sun where you live - Leduc says the amount of time needed can be up to 30 minutes a week.

Studies from the mid-1990s suggest a simple rule of thumb for sun exposure: About five minutes a day in just a diaper during the summer, or about 20 minutes a day during colder weather with your baby’s face exposed, is adequate.

Since vitamin D is stored in your baby’s liver, it isn’t necessary to get those 20 minutes every single day. In the summer, it’s safer to make your outdoor time before 10 a.m. or after 3 p.m. Sunscreen does block the rays that stimulate vitamin D production, so you might want to apply it to your older baby only after he’s had a few minutes to benefit from sun exposure. (Sunscreen should not be used at all on babies under six months.)

Given that information, Leduc says there is always room for common sense and being practical. “I’m comfortable with some degree of compromise in the summer, but then parents may forget to start adding vitamin D when winter comes,” he points out. “So I think the safest approach is to take it all the time.”

Newman argues that recommending vitamin D for every breastfed baby sends a message that breastfeeding is deficient. He also points out that many parents find the supplements expensive - a worthwhile expense in those situations where they are needed, but a waste of money if they are not. In addition, some babies don’t react well to the vitamin drops; one of McKellar’s friend’s daughters threw up every time she was given the supplement.

Where you live in Canada may also be a factor in making the decision.In southern Ontario, where McKellar lives, getting plenty of sunshine isn’t a big challenge. In much of northern Canada, it may be more difficult, especially over the winter months. Leduc adds that in northern Canada, the CPS recommends twice as much vitamin D supplement for infants.

It’s clear that the CPS and some breastfeeding advocates disagree on this issue. “I think you need to look at your individual situation and use common sense,” says McKellar. “Breastmilk isn’t defective; it’s the perfect food for infants. On the other hand, there may be some special situations where babies need supplementation. You can talk to your doctor and decide if you fit into those categories.”

December/January 2002