Another dietary supplement to avoid: calcium

Despite the claims on the package, these

pills don't give you strong bones.

Dietary supplements and vitamins are a multi-billion dollar business, driven by heavy advertising and constant promises that supplements will somehow make you healthier. For most people, vitamins and other dietary supplements are useless, and when taken in large quantities they can even be harmful. (See my article, "The Top Six Vitamins You Should Not Take" for specifics.)

Now we can add another supplement to the list of those that you shouldn't take: calcium. Calcium supplements are often sold on the promise that they strengthen your bones or prevent osteoporosis. Given that calcium is a major component of our bones, it seems sensible to assume that extra calcium might help strengthen them.

What seems sensible, though, doesn't always turn out to be true. A large new study published recently in the Journal of the American Heart Association shows that taking supplemental calcium leads to an increased risk of heart disease, by increasing the calcification of your arteries. That's a bad outcome.

The new study, led by John J.B. Anderson of UNC Chapel Hill and Erin Michos at Johns Hopkins University, looked at changes in coronary artery calcification over a 10-year period in 2,742 adults. Calcification of the arteries is strongly associated with heart attacks and other life-threatening events; basically, a calcified artery is a dangerously unhealthy artery.

The study found some surprising results that seem at first to be contradictory: people who simply consumed the most calcium through their diet had a slightly lower risk of calcification of the arteries - about 27% lower than the group with the lowest amount of dietary calcium. However, people who took calcium supplements had a 22% higher risk of calcification.

Why are calcium supplements harmful when dietary calcium seems healthful? The authors explained:

"Little of the additional calcium provided by calcium supplements, however, is incorporated in bone by adults."

In other words, if you just take a pill of concentrated calcium, your body can't handle it, and some of it seems to end up in the linings of your arteries, where it makes them rigid and contributes to cardiovascular disease. So rather than strengthening your bones, supplemental calcium might "strengthen" your arteries, but in a bad way. As the study explains:

"Rather than promoting bone health, excess calcium from the diet and supplements is postulated to accrue in vascular tissues." 

You don't want more calcium in your arteries. That's too bad for supplement makers, whose claims that calcium supplements "promote healthy bones" (as claimed, for example, by Nature's Way "bone formula" calcium pills) are just not supported by science. You can, though, get plenty of calcium by eating these calcium-rich foods:

1. Cheese
2. Yogurt
3. Milk
4. Sardines
5. Leafy greens such as spinach, kale, broccoli rabe, and bok choy

So if you're concerned about osteoporosis or just general bone health, skip the pills, save your money–and protect your heart–by eating a calcium-rich diet instead.

Stem cell therapy offers hope for “irreversible” heart damage

In December 2011, I reported on one of the first attempts to inject stem cells into damaged hearts. In that study, published in The Lancet, scientists grew stem cells from patients’ own hearts after the patients had suffered serious heart attacks. These were patients who had serious, irreversible heart damage. As the study leader, Dr. Roberto Bolli, said at the time, 

“Once you reach this stage of heart disease, you don’t get better. You can go down slowly, or go down quickly, but you’re going to go down.”

Amazingly, in that study, the patients got better. 14 of the 16 patients had improved heart function after 4 months, and the results were even better after one year. The stems cells grew into new, functioning heart cells.

That was just one study. Now there have been more, and the results continue to be very encouraging. Just last week, the Cochrane Collaboration published a review of 23 trials, all of them attempting stem cell therapy for heart disease. These trials looked at the use of bone marrow stem cells in patients whose hearts were failing. Unlike the 2011 study, which looked at heart attack patients, these studies looked at patients with advanced heart disease who had not suffered a heart attack. The results: overall, stem cell treatments reduced the risk of death and improved heart function, though the benefits were not as dramatic as in the patients with heart attacks. 

What is most exciting in the newest studies is the long-term reduction in the risk of death. Six of the studies reported long-term results (more than one year) on mortality. In these studies, 8 patients died out of 241 who received stem cell therapy (3.3%). In contrast, 30 patients died out of 162 (18.5%) who did not receive stem cells. The numbers are small, but this is a huge benefit: patients were about 5 times less likely to die. The Cochrane review concluded that

“The risk of mortality over long-term follow-up was significantly lower for those who received BMSC [bone marrow stem cell] therapy.”

An important caveat is that this is still “low quality” evidence, meaning that we need to see more data, on many more patients, before we can have confidence in the results. But it is still very encouraging, especially when no other treatment offers anything remotely this promising for advanced heart disease.

The evidence continues to build that stem cells can repair heart tissue damaged by heart attacks. Just a couple of months ago, Britain launched the largest study yet of stem cell treatments for heart attacks, involving 3,000 patients in Europe. This new review shows that they can help repair some of the damage from other types of heart disease as well.

Heart disease is the leading cause of death in the United States, and we should be pursuing every plausible treatment, though very few exist. Stem cells offer the hope that, for the first time ever, we might be able to reverse heart damage that was previously thought to be irreversible. Stem cell treatments are a true breakthrough, and rather than cutting medical research, as we have been doing for the past five years, we should be pouring resources into this remarkable new medical technology and the therapies that it makes possible.

Those fish oil supplements might cause cancer

Eating fish is good for you, especially fish that contain omega-3 fatty acids.  So I was surprised last week to read a new study in the Journal of the National Cancer Institute that found that omega-3 fatty acids increase the risk of prostate cancer.  The risk for both high-grade and low-grade cancer was increased with higher levels of omega-3 fatty acids.  This is a carefully done study, and the results should make anyone who is taking fish oil pills reconsider.

One reason this study caught many people off guard is that there has been much evidence showing that a diet rich in fish that contain omega-3 oils is good for you.  The Mayo Clinic says that  "eating fish helps your heart", especially fish like salmon that contain omega-3 fatty acids.  The American Heart Association (AHA) elaborates:

"Omega-3 fatty acids benefit the heart of healthy people, and those at high risk of — or who have — cardiovascular disease. Research has shown that omega-3 fatty acids decrease risk of arrhythmias (abnormal heartbeats), which can lead to sudden death. Omega-3 fatty acids also decrease triglyceride levels, slow growth rate of atherosclerotic plaque, and lower blood pressure (slightly)."

This all sounds great.  Because of the evidence about the benefits of fatty fish, supplement manufacturers have been marketing and selling fish oil pills for years, with great success.  As I described back in 2010, GlaxoSmithKline even created a high-dose omega-3 fatty acid pill called Lovaza that has FDA approval.

But the evidence for that you can get the same benefit from supplemental omega-3 fatty acids — taking a pill, that is — is much weaker.  In fact, a large review published last year in the Journal of the American Medical Association found no connection at all between supplemental omega-3 and a lower risk of heart attacks, strokes, or death in general.  Other studies have reported similarly negative results.  So it appears that fish oil pills may not have any heart benefits.

And now, with this new study, we learn that supplemental fish oil might increase the risk of prostate cancer.

The bottom line: the AHA recommendations about eating fish are probably still good ones.  The AHA website says:

"We recommend eating fish (particularly fatty fish) at least two times (two servings) a week. Each serving is 3.5 oz. cooked, or about ¾ cup of flaked fish.  Enjoy fish baked or grilled, not fried." 

But popping a fish oil pill is not going to cut it. As we've seen before, supplements often fail to show the benefits that a healthy diet offers.  So save your money and stop buying those fish oil pills — and fire up the grill and throw on a few salmon fillets for this weekend's barbecue.