番茄社区

A flagon of ale may indeed be a good source of dietary silicon, a recent study showed, but experts say any attempt to link beer drinking to bone health is not based on scientific data.

The study of 100 commercial beers in the February issue of the Journal of the Science of Food and Agriculture, by Charles Bamforth, PhD, DSc, and Troy Casey, of the University of California Davis, examined the silicon content that results from different ingredients and brewing processes.

Although a press release issued with the study prominently mentioned the link between silicon and bone health, the study itself did not look at bone mineral density or analyze any patient data at all, according to several researchers contacted by 番茄社区 and ABC News.

The authors wrote that they explored the silicon content in beer because the popular beverage has been identified as one of the richest potential sources of dietary silicon in the Western diet. The average intake is 20 to 50 mg/day.

The beers sampled contained an average of 29.4 mg/L of silicon, with a range of 6.4 to 56.4 mg/L. Beers made from a barley-based grist (as opposed to wheat-based beers ) and brews containing more hops had the highest silicon levels.

The beer type with the overall highest silicon level was India Pale Ale, with an average of 41.2 mg/L. Other ales came in second with 32.8 mg/L.

Nonalcoholic beers, light lagers, and wheat beers had the least silicon.

In the end, the authors concluded that "beer is a substantial source of silicon in the diet" and that "beers containing high levels of malted barley and hops are richest in silicon," but they did not attempt to establish a link between beer drinking and bone health.

Experts contacted for comment on the study also cautioned the public against establishing any such connection.

"To conclude any bone health benefits from this study would require a great leap," Tim Byers, MD, MPH, deputy director of the University of Colorado Cancer Center in Aurora, wrote in an e-mail.

Other researchers noted that previous studies have shown an association between alcohol consumption and an increased risk of fracture.

That's probably because of a greater chance of falling after drinking, according to Walter Willett, MD, DrPH, of the Harvard School of Public Health.

In fact, Stephen Richardson, MD, an endocrinologist at NYU Langone Medical Center, noted that "alcohol consumption is a risk factor for osteoporosis."

Still, there is some evidence supporting a positive link between overall dietary silicon and bone health.

A 2004 cross-sectional study in the Journal of Bone and Mineral Research that used data from the Framingham Offspring cohort found a significant association between greater dietary silicon intake, including that from beer, and higher bone mineral density in the hip in men and premenopausal women.

The researchers concluded: "These findings suggest that higher dietary silicon intake in men and younger women may have salutary effects on skeletal health, especially cortical bone health, that has not been previously recognized."

Another study by the same group published last year in the American Journal of Clinical Nutrition found that moderate consumption of alcohol, including beer, wine, and liquor, was associated with higher bone mineral density in men and postmenopausal women.

However, it also showed that men who drank too much liquor were more likely to have lower spine and hip bone mineral density.

The relationship between beer and bone mineral density appeared to be mediated by silicon, the researchers concluded.

Bottom line: considering the increased fracture risk and the various other problems associated with drinking too much alcohol, experts agree that guzzling beer is not strategy for improving bone health.

"In the absence of bone density values or preferably fracture incidence, it would be premature to tout beer as a preventative or treatment," Richardson said.

David Katz, MD, MPH, of the Yale School of Public Health, agreed.

"This is NOT a reason to drink beer," he said in an e-mail. "This is simply a bit of good news for those who do drink beer already -- yours truly among them!"

This article was developed in collaboration with ABC News.

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