PSA: please don't take medical articles in the mainstream/layman media seriously. Talk to a doctor.

(The article does make a point of qualifying the findings to people over 50, so perhaps things are completely different at that age, but the articale is missing important information (the role of vitamin K2, see below) and the headline doesn't make any mention of it and it sounds like some people are taking it too generally, so I will go ahead with my story (I am under 50).)

Due to my (admittedly, unbalanced) vegan diet I developed severely low bone density. This was confirmed by a DEXA scan (for bone density; https://en.wikipedia.org/wiki/Dual-energy_X-ray_absorptiometry). The reason I noticed a problem was that I compression-fractured my T7 vertebra snowboarding (just riding down a hill, basically, not from a fall).

My doctor put me on a combined calcium, vitamin D, and vitamin K2 supplement (Menacal 7). 18 months later the DEXA scan showed a marked improvement. And I have been snowboarding many times since, and I skateboard all the time, and I have taken heavy falls but have not fractured any bones. So I have medical and anectdotal proof that the supplements worked very well for me. I am still on them and I fully expect to have made even more progress next time I take a scan (maybe 10 months from now).

The Menacal people built the K2 into the supplement because it counteracts the "excess calcium in the arteries and kidneys" effect that the article talks about (https://en.wikipedia.org/wiki/Vitamin_K2#Heart_calcification). This solution to this problem has been known for a long time (paper in 2004; 10-year studies confirming it in 2008, 2009), yet the posted article doesn't even mention K2!

A second review, also led by Reid, found that people who ate the most calcium in their diets, mostly from dairy sources, tended to have slightly stronger bones as measured by bone mineral density, but this didn't translate into fewer broken bones.

Common sense dictates that bone density is a much more important metric than "likelihood to suffer broken bones". And in my case calcium supplements made a huge improvement in my bone density.

Also see another post of mine for more info: https://www.reddit.com/r/vegan/comments/3ins7y/sam_harris_prominent_atheistpublic_intellectual/cuicp14