Dr.  Keith Roach

Dear Doctor. Roach: Please explain the difference between probiotics and prebiotics? I know they are both helpful for the digestive system, but I’m not sure why.


Dear AB: Prebiotics are indigestible food ingredients, such as fiber, that promote the growth of beneficial microorganisms in the intestines. Probiotics are the healthy organisms themselves, like Lactobacillus and others. Suggested benefits include treating and preventing allergic diseases, treating various bowel diseases such as inflammatory bowel disease and infectious diarrhea, and relieving symptoms of depression. However, the purported benefits of prebiotics and probiotics have not been proven to the point of consensus among experts.

Our understanding of the intestinal microflora is still in its infancy. While I believe that people with certain medical conditions have potential benefits, it is still not clear what conditions they should be used for and what specific products to use. More importantly, many people use both prebiotics and probiotics in the absence of illness or symptoms. I do not recommend this as there is no convincing evidence that they are effective at preventing disease.

A healthy diet includes foods that contain prebiotics and, in the case of yogurt and other foods with active healthy bacteria, may also contain probiotics.

Dear Doctor. Roach: I am a 75 year old man in good health. I have osteoporosis of the spine and three broken vertebrae. I have back pain every now and then, but I feel lucky that I can run and move as much as I can. Sport is part of everyday life in my life. A year ago I couldn’t walk at all because my pain didn’t stop.

I have studied all types of osteoporosis treatments. There are quite a few, but no cure for the problem. The side effects of the treatment force large numbers of people to stop taking it. Nobody will recommend any particular treatment to me. I’m taking the recommended dose of vitamin D and calcium supplements, but I’m reluctant to start chemical treatment. Am i stupid to wait

– GW

Dear GW: If you have a history of three fractures, it is not advisable to refuse therapy beyond vitamin D and calcium. The next fracture could be worse than the three you had before. Vertebral fractures are usually painful and can compress the nerves on the body, with complications such as worse pain, weakness, and numbness. Worse still, a hip fracture is a devastating injury that usually requires major surgery and is always associated with significant risks.

I don’t have enough information about you to recommend any particular therapy. I will say that men with osteoporosis should always have testosterone levels under control, as low testosterone levels are often associated with osteoporosis and testosterone treatment increases bone density (although it has not been proven to reduce the risk of fractures). Most men with osteoporosis are treated with antiresorptive therapy such as alendronate or risendronate.

You are right that many people stop treatment. In randomized studies, about 30% of patients stop treatment, although this number was roughly the same for those assigned to placebo. Most people can tolerate the side effects well with the help of a provider who has experience in the management of this condition.

Especially for someone like you with a history of multiple fractures, the benefits of treatment far outweigh the potential harm.

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