Controversial headlines attract readers – which sells more advertising – but it’s wrong to lead with a headline that can cause readers to act against their own interests.  This is what Fox News, US News, and multiple other news sources did with identical headlines on February 13, 2013:  “Calcium Supplements may raise odds of heart death in women.”  Technically, the article (that is the same word for word on multiple websites) states that sometimes a calcium supplement could be harmful, but many women took the headline to mean they should stop taking all calcium supplements because they “… may raise odds of heart death in women.”    

The statement in the headline is true – in very specific circumstances that do not apply to most women – but the headline can also be read to suggest it’s risky to take any calcium supplement whatsoever. 

Yet another study of calcium intake

The press story refers to a Swedish study published February 12, 2013 in the online version of the British Medical Journal.  The abstract is available on line [click here].  The researchers reported cardiovascular mortality in women in relation to their calcium intake.  Calcium intake was estimated based on two surveys:  an initial survey taken between 1987 and 1990 when women were enrolled in the study, and a second survey in 1997. 

For their analysis, researchers classified women into four groups from low to high calcium intake: less than 600 mg per day, 600 to 999 mg per day, 1000 to 1399 per day, and 1400 or more mg per day. 

To put the article in perspective, it is important to know that the Institute of Medicine in the United States recommends 1000 to 1200 mg per day.  And, the same Swedish researchers previously reported that between 750 and 1025 mg calcium per day is enough to prevent osteoporotic fractures, i.e. broken bones because of weak bones [click here].

Very low and very high amounts of calcium are associated with higher mortality.

When they looked at death in relation to calcium intake, women in the very low group (less than 600 mg per day) and in the very high group (1400 or more mg per day) had an increased chance of dying from heart disease.

In contrast, there was no significant difference between the two middle groups, the women who had 600 to 999 mg per day and those who had 1000 to 1399 mg per day.  In fact, there was a consistent hint that the 1000 to 1399 did slightly better overall, but this did not reach statistical significance.

The effect of calcium supplements specifically

These results were the same whether a woman got her calcium through food in her usual diet (typically with a lot of dairy products) or used a calcium supplement or both.

They also looked at women who took calcium tablets (which are usually 500 mg per tablet in Sweden).  Women in the 1000 to 1399 group still had slightly lower risk of death even if part of their calcium was from a calcium supplement or calcium included in a multivitamin. 

Who increased their risk with calcium supplements?

Women who took over 1400 mg of calcium per day and had part of that calcium in the form of a calcium pill, had an increased risk of dying of heart disease. 

Who takes over 1400 mg calcium of calcium per day anyway?

The guidelines for dietary calcium are 1000 to 1200 mg per day.  However, some physicians and some nutritionists recommend much higher intake.  There is no data to support benefit from a higher daily intake of calcium, and as just reported, high amounts of daily calcium intake may be risky.

Confirmation from the AARP

In a quirk of timing, a separate study of 169,170 AARP women members published February 4, 2013 found no relation of total calcium to mortality [click here].  They also looked specifically at calcium supplements separate from total calcium, and, although it was not statistically significant, observed a slight trend toward higher heart death with more than 1000 mg of calcium supplement per day.  [The same study followed 219,059 men and found that over 1000 mg of calcium supplement per day was significantly associated with increased heart attack death, especially in men who smoked tobacco.]

Should I take a calcium supplement?

The key to whether you need a calcium supplement is how much calcium you already get through your usual diet.

As discussed extensively in a previous Perspective on Women’s Health [click here], your personal decision should be based on how much you use dairy products, broccoli and kale, or canned sardines on a regular basis.  (And believe it or not, according to the USDA, General Mills Total Raisin Bran Flakes have a lot of calcium).  You can estimate your daily calcium using the US Department of Agriculture website [click here]. 

If you eat sufficient dairy products daily – which means at least two servings of milk, cheese, yogurt, cottage cheese, or ice cream, etc. each day as part of your regular diet – you may not need a calcium supplement.  If you get less than two servings of dairy per day, it’s difficult to get enough calcium consistently, and your total intake may be less than 600 mg per day. According to this article, such low calcium intake would increase your risk of cardiovascular death, and you would benefit from a calcium supplement.

What should have been the headline?

An accurate headline for Fox News, US News, and the others would have been, “Super high dose calcium supplements appear harmful: usual recommendations for calcium intake are confirmed.”

It would not have drawn as much attention, but it also would not have been misleading.


We have recently published further studies of the effects of BPA, including the observation that curcumin, the active ingredient in the spice turmeric, can reduce the effects of BPA (bisphenol-A). Both the abstract [click here] and the full article [click here] are on line and can be downloaded free. 

This article underscores the connection between BPA and increased cell growth that we suspected from our first studies over five years ago and suggests that curcumin, or a similar drug, may be useful to reverse the effects of BPA.

Looking at cells before they are cancerous.

There is a lot of research looking at how BPA affects cancer cells, but that doesn’t help us understand the origins of cancer because the cells are already cancer.  To study the origins of cancer you have to start with benign cells.

In our research, we start with cells that are not cancerous and look at what BPA does to these cells.  We have identified two ways that BPA changes non-cancerous cells and makes them behave like cancer cells.

BPA stimulates cell growth.

Non-cancerous breast cells usually grow slowly.   Estrogens stimulate these cells to grow faster, and this is part of the way that estrogens and the synthetic estrogen, DES, contribute to breast cancer.

BPA stimulates growth of non-cancerous breast cells just like estrogens. 

The worry is that, once stimulated by BPA, some cells will continue to grow on their own.

Encountering our worst fear.

In this paper we report the event that we all fear:  some non-cancerous cells continued to grow unusually well even after the BPA was gone.  This is the kind of uncontrolled cell growth that could lead to cancer.

Fortunately, this was a rare event, but remember that not everyone exposed to any cancer-causing agent gets cancer.   For example, radiation exposure is a risk factor for many cancers, but only a small fraction of the people who are exposed to radiation go on to get cancer.  In fact, it would be suspicious if all of our cells continued to grow after BPA was removed.   However, that it happened even one time reinforces the parallel to other dangerous exposures. 

BPA helps cells stay alive.

When the body is functioning normally, damaged cells go away by a process called apoptisis (ay-pah-TOE-sis) or programmed cell death.  Although it is called “cell death” apoptosis is really a special way that damaged or unnecessary cells break up and go away.  All cells are capable of this.  It is a little like a scuttle on a ship.

Apoptosis is important because it is the way that cells damaged by radiation, chemotherapy, or hormone therapy go away.  If apoptosis does not work, cells can continue to grow abnormally and not die.  This happens in cancer, and in fact, evasion of apoptosis is a prerequisite for a cell to become malignant. 

BPA causes cells to evade apoptosis

When we exposed cells to tamoxifen, they should have undergone apoptosis, but they did not.  This means that BPA gives cells the ability to grow when they should be stopped by anti-cancer or cancer preventing drugs.   This brings these non-cancerous cells potentially closer to being malignant, especially if the effects persist after the BPA is gone, as we found for growth of some cells. 

The Curcumin Connection

Curcumin is the chemical in the spice, turmeric, that makes curry yellow.  It is a traditional remedy in many cultures, and it has thousands of years of use to suggest that it is safe.

For the last 20 years, researchers have wondered if curcumin might have direct anti-cancer effects.   Relevant to our research, these researchers found that curcumin directly affects the same genes that are controlled by mTOR, but it has the opposite effects from BPA.  Curcumin makes cells less likely to grow and more likely to undergo apoptosis. 

This research suggested that, even if BPA activated mTOR, curcumin might reverse the effects because it directly blocks the same genes that mTOR activates – in essence, it looked like curcumin might “do an end run” and reverse the effects of BPA.

We found just that.  Curcumin reversed the effects of BPA that made cells grow abnormally and survive if they were damaged.  Most important, the cells that kept growing after the BPA was removed, were also stopped by curcumin.

There are two important conclusions from this study. 

Convince the skeptics.

Scientists influence official beliefs about environmental chemicals.  However, scientists tend to be skeptical.  They want to know, “How does BPA work?”   We can now answer their question.  We can show that BPA modifies activity of known genes, and then we add that a known blocker of those genes, i.e. curcumin, reverses the effects of BPA.  This is the kind of add-then-subtract double proof that scientists demand.  

The situation is not hopeless.

It may not be possible to eat enough curry to reverse the effects of BPA, but it is important to know that the effects are not irreversible.  [Supplements of curcumin are on the market, but there is no data yet on how much curcumin you would need to take to protect yourself from BPA.]

Demonstrating reversal of the effects of BPA provides a tangible goal as we try to prevent breast cancer and other effects of endocrine disruption in humans.   We need to know it is possible to help.

Should we eat more curry?

Yes, eat more curry if you like it.  Know that it might help, but we don’t know yet how much it might take to be beneficial.  Researchers are working on that.

A complete pathway.

This study completes a picture of how abnormal activation of a series of genes in a whole pathway can cause cells to grow abnormally.  For more discussion of cell pathways, see Perspectives on Womens’ Health from August 21, 2012.  [click here]

For those who want to read more, the effects of BPA on major genes include:

Increased PI3K, AKT, mTOR, and cyclins and decreased PTEN and p53.