I just blogged about how I started calcium. You know, prompted by my mom’s terrible hip fracture (okay, there is probably no good hip fracture, but hers was particularly nasty).
I will confess that I have never been on the vitamin band wagon. I managed to choke down prenatal vitamins for 22 weeks, but then when my pregnancy went to hell in a hand basket, I thought, “‘Ha, just as I expected.”
I’ve always felt the best source of vitamins, minerals and other goodies that keep our parts working are best derived from a balanced omnivorous diet, preferable low in fat. When the study came out recently that vitamin takers were more likely to die early, I felt vindicated in my belief that we are meant to slowly digest vitamins and other nutrients, not get them in a bolus (understand this approach doesn’t apply if you have a deficiency, but rather to the otherwise healthy, non-nutritionally deficient population).
But the hip fracture hip close to home. I reviewed the Institute of Medicine’s recommendation that a 45 year old woman should have 1,000 mg of calcium a day. I figured I was getting 400-500 a day from my diet, so added in a 600 mg daily supplement.
And then I did some additional reading today at lunch and, well, holy calcium controversy batman.
A recent article from the British Medical Journal re-analyzed the Women’s Health initiative (Bollan et al, BMJ 2011342:d2040) and calcium supplements with or without vitamin D actually increased the the risk of cardiovascular events (which are not good events, like parties, in case you are wondering). Especially heart attacks. The study estimates that treating 1000 people with calcium for 5 years will prevent 3 fractures and cause six heart attacks! Yikes.
So I read more. Calcium, it turns out is pretty good at slowing bone loss (Tang et al. Lancet 2007), but it only seems to be helpful in reducing fractures for people at greatest risk (elderly, low calcium intake, living in an institution etc). Although, to tell you the truth there was so much back in forth in the various studies between “calcium helps prevent fractures” and “calcium doesn’t reduce fracture risk” that I was getting vertigo.
It seem there are studies on both sides of the table. Calcium increasing heart attack risk and calcium not having a negative effect. Calcium helping bones and calcium not really reducing fractures. At times, I wonder if we torture the numbers enough if they will simply to confess to anything?
The few things my non-endocrinologist brain could glean from the 14 papers (yup, 14) that I read (honestly, I didn’t have the stomach or balance for more) were the following:
– the risk of heart attack for women was not increased with a dietary calcium intake below 800 mg a day
– cardiovascular “events” are predominantly seen in studies with calcium supplements of 1,000 mg a day or more
– if you have kidney disease (like I do), calcium is even more likely to be bad for your heart and blood vessels.
– an optimal vitamin D level (and God, that’s a controversy in itself) is needed
– calcium from food is good for bones
My plan for osteoporosis prevention: salmon and yogurt (and
Oh, and I will never, ever again write a post sourced alone from the Institute of Medicine.