ALEX COHEN, host:
This is DAY TO DAY from NPR News. I'm Alex Cohen.
MADELEINE BRAND, host:
And I'm Madeleine Brand.
I'm looking at the ingredient list on a box of Cheerios and the vitamins and minerals in here just go on forever. There's vitamin A, vitamin C, calcium, iron, vitamin D, etc., etc.
Americans have been fortifying their food since 1924. That's when iodine was added to salt to prevent goiters, a thyroid condition. And now, well, there's vitamin D in milk, folic acid in flour, fluoride in our water. Is all this fortification necessary and is it good for us?
Dr. Sydney Spiesel is our resident medical expert. He's here to talk about some new research on the topic. And welcome to the program.
Dr. SYDNEY SPIESEL (Yale Medical School): Thank you. Always nice to be back.
BRAND: Syd, there's a new study on folic acid and I know that pregnant women and women who want to get pregnant are advised to take folic acid to prevent birth defects. What does this new study say?
Dr. SPIESEL: Well, folic acid is particularly important and is routinely part of fortification of flour now because it turns out that folic acid helps prevent spina bifida. People had a suspicion that folic acid might be helpful in terms of cardiovascular disease. And so there are couple of studies that were done in which people looked at that very question. And interestingly enough, wrong. You know, it turned out it really was not helpful except in one little side benefit, which it turned out that folic acid - it's now been shown a couple of times over - as a supplement to food in some studies seems to decrease the risk of stroke.
BRAND: Oh, so hardly minor. That's a...
Dr. SPIESEL: Oh yeah. No, no. I think it's significant and important.
BRAND: So are they recommending that adults take folic acid supplements or drink a lot of orange juice?
Dr. SPIESEL: Within reason. I mean, I think that the notion for a while is that people ought to have an adequate amount of folic acid in their diet; although probably it's not necessary to have huge amounts.
BRAND: And you also reviewed another study on fortified food.
Dr. SPIESEL: Yeah. That was an interesting one. You know, one of the ways that we've been fortifying foods for years has been to add iron. We put iron in infant formulas, we put iron in baby cereal and iron is often added in small amounts to flour, in much the same way that vitamins are added to flour as a way of preventing anemia or decreasing the risk of anemia.
It clearly has been pretty effective WHEN IT'S added to white flour, but it turned out that there's an ingredient in corn flour - and cornmeal flour is, you know, is an important staple in much of the world - which decreases the absorption of the traditional method of fortifying cornmeal flour.
BRAND: This sounds like it would be very beneficial in the developing world, where people eat a lot of maize and a lot of corn flour. But here in this country, people do eat a lot of meat - it has iron in it. And as you say, flour is fortified. Is it necessary?
Dr. SPIESEL: It's hard to know. Probably the levels of fortification that we're using now, it will mostly just serve to prevent anemia. And I think it's still a good idea. There are a lot of people who really - who are not getting adequate amounts of iron.
BRAND: I started this off reading this incredibly long list of vitamins and minerals in a box of Cheerios. Is it - you know, and then one reason, obviously, why people buy it, they think they're getting all this good stuff. Is it possible to get too much of this stuff?
Dr. SPIESEL: Well, it's certainly possible to get too much of vitamins. And there are many, many cases known of people who have been essentially poisoned, especially when they're taking vitamins which are the oil-soluble vitamins like vitamin A and vitamin D.
The levels of vitamins which are currently recommended are - they are really set at pretty safe levels. I think people really don't need to worry about that. But I do worry sometimes about people who are little gung-ho and start thinking that if a little bit of vitamin is good, a lot must be really terrific, which is not true at all.
BRAND: What about taking a daily multivitamin?
Dr. SPIESEL: I think a single daily multivitamin is very reasonable. Do I think it's useful? Well, that's another story. My own belief is that in general if you're eating what seems to me to be a well-balanced diet, some fruits and vegetables, probably some meats, except for people who are vegetarians, in which case you have to fiddle around a little bit, you probably don't need any additional vitamins beyond that.
BRAND: That's opinion from Dr. Sydney Spiesel of the Yale Medical School. You can read his medical examiner column at slate.com.
Thanks for joining us again, Syd.
Dr. SPIESEL: Thank you.
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