Most of the posts on this page will relate to things you can do or things you should know to improve your health. This post is an exception. It’s about what you can do to help other people’s health. It’s a reminder to give blood.

I’ll be donating this Sunday at a blood drive for the Red Cross.

You may not know that every unit donated is separated into three products – red blood cells, platelets, and plasma. Each is given to a patient who needs that specific product so each donation has the potential of saving three lives. So please go to the American Red Cross blood donation website and find a convenient place and time to donate. Three strangers will be glad you did.

Thank you.

Last week’s New England Journal of Medicine article publishing the results of a large National Institutes of Health (NIH) study on the effects of calcium and vitamin D supplements on risk of bone fracture and the risk of colon cancer has generated much media attention. The results were disappointing to some, but I believe that they help make our expectations of calcium and vitamin D more realistic.

You can review the results of the study in this NIH news release.

The result on colon cancer prevention is quite clear: calcium and vitamin D has no effect on the incidence of colon cancer.

The result on fracture prevention is more complex. (The details are in the review linked above.) Overall, there was no statistically significant difference between fracture rates in women taking calcium and vitamin D and women taking placebo. The problem is that many of the women had stopped taking the supplements by the end of the study. Women who were still taking the supplements, as well as women over 60, did have fewer fractures than women taking placebo. There was also a small but significant increase in the incidence of kidney stones in the women taking the supplements. Joan McGowan, PhD, who was a coauthor of the paper, summarizes the results well.

“If we look at all the findings together,” said McGowan, “for every 10,000 women treated for one year, two hip fractures would be prevented and five cases of kidney stones would be caused. The number of hip fractures prevented would climb to four for compliant patients and six for women over 60. Since hip fractures are considered to be more serious than kidney stones, on balance, the public health benefit of the supplements outweighs the risks.”

So I’m still recommending calcium and vitamin D supplements for my post-menopausal patients. My patients and I just have to understand that the benefit we’re expecting is smaller than we thought.

This article published yesterday in the Los Angeles Times features a great summary of the current scientific evidence about preventive care. (Registration is required by the Times to read the article, but is free.) Some of what is known may surprise you. The annual physical examination – for example listening to the heart and the lungs, feeling the belly – likely has no benefit to a healthy patient who is feeling well. Only a small number of preventive tests have been proven to help save lives and detect important diseases early. This includes screening for high blood pressure, high cholesterol, diabetes, and colon cancer.

I recommend you read the whole article with special attention to the bulleted list at the end. This list very well summarizes all of the preventive tests that have proven value. Other tests done on healthy people with the intention of catching diseases early, such as annual stress tests or chest X rays or CT scans, simply don’t work.

The most authoritative and unbiased recommendations on the value of various preventative healthcare tests are made by the U.S. Preventive Services Task Force. They are cited extensively in the Times article.

Finally, I’m delighted that the article stresses the value of physician counseling in the annual exam. The advice to quit smoking, to diet, to exercise, to strike a better balance between work and leisure, or to wear seatbelts can be much more valuable than any test, and as I’ve seen many times in my own practice, can dramatically redirect a patient’s life in a healthier direction.

This very large study of the effects of diet on the incidence of breast cancer was just published today in The Journal of the American Medical Association and has received much media attention, including this article in the Los Angeles Times. The study is important because of its size (over 48,000 women were studied) and because it was one of the few studies of the effects of dietary change that actually involved randomizing women into the low fat or the standard diet group. This randomization makes the results much more reliable than studies in which the subjects decide themselves what to eat.

The results showed the same incidence of breast cancer in both groups of women. Approximately one in every 230 women in each group developed breast cancer.

Some are interpreting the study with caution, warning that the women in the low-fat diet group may have still had too much fat in their diets to decrease their risks, but if that’s the case, it’s probably not realistic to expect women to lower their dietary fat much further. The other possible interpretation is the obvious one: that there is no link between dietary fat and breast cancer.

Links between diet and cancer incidence have always been speculative, and in other diseases like heart disease and obesity dietary fat is being found to be less important than total calories consumed and exercise. Unfortunately, breast cancer prevention remains elusive, and the best we can do at this point is early detection.

In his State of the Union Address this week, the President specifically praised electronic medical records.

We will make wider use of electronic records and other health information technology, to help control costs and reduce dangerous medical errors.

Our office has had electronic medical records from the day we opened, three years ago. I believe that electronic records make possible improvements in patient care that are impossible with paper charts. Automatic checking for drug interactions and secure access from remote locations are just two examples. Our office has been such enthusiastic proponents of electronic records that the company that makes our medical records software, A4 Health Systems, published a case study of our practice.