Category Archives: Cacao

Chocolate Bad for Bones


Chocolate consumption and bone density in older women.

Nutrition is important for the development and maintenance of bone structure and for the prevention of osteoporosis and fracture. The relation of chocolate intake with bone has yet to be investigated.
We investigated the relation of chocolate consumption with measurements of whole-body and regional bone density and strength.
Randomly selected women aged 70-85 y (n=1460) were recruited from the general population to a randomized controlled trial of calcium supplementation and fracture risk. We present here a cross-sectional analysis of 1001 of these women. Bone density and strength were measured with the use of dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and quantitative ultrasonography. Frequency of chocolate intake was assessed with the use of a questionnaire and condensed into 3 categories: or=1 time/d.
Higher frequency of chocolate consumption was linearly related to lower bone density and strength (P<0.05). Daily (>or=1 times/d) consumption of chocolate, in comparison to Older women who consume chocolate daily had lower bone density and strength. Additional cross-sectional and longitudinal studies are needed to confirm these observations. Confirmation of these findings could have important implications for prevention of osteoporotic fracture.

Hodgson JM, Devine A, Burke V, Dick IM…
Am. J. Clin. Nutr. Jan 2008
PMID: 18175753 | Free Full Text

This is disappointing. Cocoa is normally so healthy. My first thought was that they may be seeing the effects of sugar. Reading the full study, which is available for free using the link above, the authors made these comments:

Chocolate is usually also rich in sugar and contains the methylxanthines, theobromine and caffeine (27), and oxalate (11, 12)….

Oxalate is a potent inhibitor of calcium absorption (13). Furthermore, a single 100-g dose of dark chocolate was found to increase calcium excretion by 147% (14). The basis for this is not clear, but it is likely to include an effect of sugar to increase urinary calcium excretion (14, 15), dependent in part on an increase in plasma insulin that itself stimulates calciuria (29).

I wonder what would happen if you consumed a very dark chocolate (so very low in sugar) and supplemented calcium and vitamin D? The idea being that the very dark chocolate would avoid most of the sugar, and the calcium and vitamin D would hopefully overcome the reduced calcium absorption.