497: Does calcium consumption make sense? Dr. Nina Radford from Cooper Clinic weighs in

Hi, this is Todd Whitthorn with another Healthy Living Podcast, joined today by Dr. Nina Radford,

the head of cardiology at the Cooper Clinic, and if you listen to our podcasts on a regular

basis, you know that Dr. Radford is a wealth of information, and primarily we like to talk

about things related to the heart.

So Dr. Radford, today let's talk about calcium and heart disease.

Again, the headlines constantly screaming about, is calcium good, is calcium bad, how

much should we be taking, do we take it in supplement form, do we get it in food, what

should we be thinking about calcium right now?

Todd, this is a great question.

I'm asked now regularly from a lot of my patients if they should continue to take calcium or

if they should throw their supplements away, and before I could feign ignorance because

I wasn't a bone doctor and I didn't have to worry about fractures, but now there's been

a lot in the news about a potential increased risk of having heart attacks in women who

take calcium supplements.

And I want to, if you'll indulge me, sort of take a walk down memory lane a little bit

because this has really been in the news probably about the last five years or so, and there

have been a couple of meta-analyses that were published.

These are analyses of multiple studies where they group together studies that maybe have

smaller populations into one giant population, and you can do a little bit more statistical

manipulation.

And come up with conclusions the bigger the population is.

And so there were some studies that were published five years ago that suggested there may be

an increased cardiovascular risk from taking calcium supplements in older, healthy older

women.

And these analyses were done in studies that were originally designed to look at the impact

of calcium on bone fracture.

And they would go back to the study and they would look at the impact of calcium on bone

fracture.

And they would go back to these studies and look at the incidence of heart attack, stroke,

and death in sort of second-look analyses.

And from a statistical standpoint, going back to a trial and looking at outcomes that weren't

specifically described when the study was designed is a little bit tricky.

And it's tricky because there may not have been components of the design that take that

into account to make sure that the study was designed to be a good study.

And so it's a little bit tricky when you go back to studies that weren't designed to look at heart

attacks as an outcome and then make conclusions about them.

And first and foremost, one of the biggest problems with some of these studies is that when

they're not designed to look at heart attacks as an outcome, they're not designed to look at heart

They talk about the outcome of heart attacks or strokes that these are self-reported and that

patients will report they've had a heart attack.

And patients may not always have had a heart attack.

They may have had some chest pain that ended up after a workup wasn't really heart disease.

They may have had dizziness or a woozy spell that wasn't really a stroke.

And that my experience in doing these kinds of scientific studies,

is that you really need to get the hospital records and you really need to get the test results

to confirm that, in fact, a stroke was a stroke and a heart attack was a heart attack.

And many of these studies don't do that.

The other thing about these studies is some of them, after the fact, will send out questionnaires

from patients who are enrolled in a trial and say, well, what happened to you from a heart

standpoint?

And not everybody sends back their questionnaire.

And so the questionnaires...

The quality of these data sometimes are not great.

So that, I think, is an important caveat.

And when you look at the meta-analyses that have come out over the last five years or so,

some will show a little bit of an increased risk.

Some will show, in fact, a little bit of a decreased risk.

That is, they appear to be cardioprotective.

And some show no effect at all.

And so, on balance, when I see this kind of outcome,

a little bit good, a little bit bad, no effect,

what that generally means is probably there's no effect overall.

And that it depends a little bit on how the study was done, what the population was like.

So, in general, I am not particularly concerned about the impact of calcium supplements on heart

disease.

And I'll say that, though, with a couple of caveats.

And that is, of the studies that have been out there,

that demonstrate...

even a small risk, it appears that it may be related to higher doses of calcium.

In one study, it was above 1,300 milligrams.

In another study, above 1,400 milligrams.

And in general, given that we suggest that a premenopausal woman get 1,000 milligrams

and a postmenopausal woman get 1,200 milligrams,

probably for people who are eating a regular diet, the need for supplementation above that point

is probably rare.

So, for most women, I don't think it's an issue.

The other thing I'll say about all of this calcium research that's very difficult,

and you and I have discussed this before, there's really no good measure of your calcium intake.

You know, we can measure your vitamin D level.

Is it high or low?

I can measure your cholesterol level after you've just had, you know, two weeks of eating fries and,

you know,

commercially baked goods.

I can see the impact on your cholesterol level.

The same is not true for calcium.

There's calcium-fortified foods.

There's differences in the absorption of calcium, depending on what calcium supplement that you're taking.

And so, this is not precise neurosurgery.

This is very broad strokes when you talk about calcium supplementation,

particularly because a lot of these studies will ask,

will ask,

in a survey from 1996,

do you take calcium?

And then ask 10 years later, what happened to these people?

Well, if you're like most people,

you may fall off the supplement wagon and then climb back on and then fall off and climb back on.

Your diet may change.

You may have a couple of good years where you are eating very well balanced,

and then maybe you get a new job.

A parent gets sick.

You're eating in the drive-thru lane.

So, with most people,

if you look at their life over 10 years,

there are peaks and valleys of good nutrition and bad nutrition,

and supplement use and no supplement use.

So, I will tell you that all of this literature is a little fuzzy.

You know, it's sort of like a Doris Day movie,

where you look at her and everything's sort of a glow and fuzzy,

so she doesn't look like she has very many wrinkles.

But I will tell you the calcium data is a lot like a Doris Day movie.

It is through a filter.

So,

that, in general,

I don't think the risk is high.

As always, if you can get your calcium through food,

that's great.

If you need to supplement a little bit to get to the recommended daily allowances,

it's fine.

I think that this, again, is much to do about nothing

in terms of, you know,

making women unnecessarily frightened

about a risk,

that I don't think is very great and may only be evident at very, very high doses.

Very good.

One more question about calcium.

Does calcium supplementation increase your risk of coronary calcification,

as measured by the MDCT tests that they do here at the Cooper Clinic?

That is a great question,

and there's been a recent study that suggests there's no relationship at all.

That the calcium that we have in our arteries is a process of healing,

healing from inflammation.

It's kind of a normal biologic process,

and it's not been shown to be impacted by the use of calcium supplementation.

Perfect.

Always great to go to the source,

and we appreciate it.

Dr. Nina Radford, head of cardiology at the Cooper Clinic.

If you'd like more information,

you can find it on the website at cooperorobics.com,

where we have more podcasts,

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So, we hope to keep you up to date on a regular basis.

We appreciate you listening.

Have a wonderful, healthy day.

See you soon.