Tuesday, June 25, 2013

More evidence of powerful breast cancer prevention

We have previously pointed to the strong evidence that use of selective estrogen receptor modulators (SERMs) substantially reduces risk of breast cancer. New updated data has been published in the British journal Lancet (May 25, 2013). The original data from all patients in a number of trials of these agents for prevention for breast cancer were combined using common analytic methods. The authors report that across 9 prevention trials and 83,339 women randomized to SERMS and followed for an average of 65 months, had a significant 36% reduction in invasive breast cancer. The reduction in risk is stronger for estrogen receptor positive breast cancer.

New insights in this report include the protection from taking SERMs persists for 5 or more years after stopping. Also risk of vertebral (spine) fractures was significantly reduced by 34%. This improves the benefit to risk trade-off that this and other drug based prevention strategies require.

The good news is that the adverse effects form taking SERMs are now well documented and low frequency.

From this analysis the authors draw on the extended follow-up and estimate that for every 42 women treated with a SERM for 5 years one case of breast cancer will be prevented within 10 years of beginning therapy.  This is similar to our early post in which we pointed to our paper from 2008 showing that for 5 years of use among women 65 to 69 one case of invasive breast cancer would be prevented for every 43 women treated, and for women 60 to 64 in the top 10% of breast cancer risk in the population, one case would be prevented for every 53 women given the chemoprevention drug.

We recently noted that use of SERMs is much lower than might be expected given the substantial reduction in breast cancer with use of these drugs. The FDA approved the use of Tamoxifen for primary prevention of breast cancer in both premenopausal and postmenopausal women at high risk. This approval was in 1998. In 2007, the FDA approved Raloxifene for primary prevention of breast cancer among postmenopausal women.

And for breast cancer prevention, see: Cancer News in Context: Breast cancer prevention

Monday, June 10, 2013

Why It's Important That Many of Us Underestimate Fast Food Calories

A study published last month in the British Medical Journal (BMJ) showing that people regularly underestimate the amount of calories contained in fast food meals garnered a good deal of media attention (paper) and remains a "most read" listing on the BMJ.com site.  With good reason.  While moves are being made to prominently list the calorie contents of foods in restaurants, and the obesity epidemic is showing few signs of abating, the researchers from Harvard Pilgrim Health Care in Boston found that a large proportion of people underestimated the number of calories in their meals by a very large amount -  500 calories or more.  What makes this so significant is that even small imbalances in the calories we bring in versus what we burn through daily activity can lead to weight gain over time.  Seeing reality-versus-perception numbers as large as 500 calories for a single meal can make health care professionals shudder.

Of course, underestimating the calorie content of a meal doesn't directly translate to weight gain.  Just because someone thought their meal was 500 calories, and it was actually 1,000, doesn't mean they'll eat any more or fewer calories over the course of the day than if they had better calorie estimation skills.  But it's certainly possible, especially if someone thought they were making a lower-calorie, healthy choice (and actually weren't).

And this relates to one of the most interesting findings in the study.  Of the five fast food chains included in the analysis, the one with the largest discrepancy between estimated and actual calorie content of meals was Subway (figure) - the restaurant that through its promotions and spokesman, Jared, is most often linked to healthy choices and weight loss.  This "health halo," as the authors describe it, can lead people  to think they're making healthy choices when in fact they may be eating many more calories than they think they are.

While there are a number of important healthy eating tips that can lower the risk of diseases like diabetes, cancer, heart disease, and stroke, one overarching tip is to keep calories in check.

Weight gain and obesity are major risk factors for all kinds of major diseases, so keeping calories in check, and therefore, weight in check should be a primary health goal for everyone.  And it doesn't matter where the food comes from, really - fast food restaurant, fancy restaurant, farmers' market, grocery store - a calorie is a calorie is a calorie, and it's important to not eat too many of them.