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Skirt size increase linked to breast cancer risk, study finds 
  
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 Women who go up a skirt size every decade between their 20s and their 60s may be at increased risk of postmenopausal breast cancer, a new study suggests. 
  
 Researchers found that an increase of one size every 10 years led to a 33 percent rise in the risk of postmenopausal breast cancer, while an increase of two sizes per decade let to a 77 percent rise in risk, according to the study in the journal BMJ Open. 
  
 Although other studies have looked at the impact of weight on breast cancer risk this is the first study to look at weight gain — and with a measure that is easily assessed by women and their doctors. 
  
  
  
 “We were pleased to find an association between skirt size change, which is easy to recall, and breast cancer risk in postmenopausal women,” said study coauthor Dr. Usha Menon, head of the Gynaecological Cancer Research Center at University College London. 
  
  
  
 The advantage of scrutinizing skirt size is that it gives a window on the issue of abdominal fat, said Dr. Kandace McGuire, an expert unaffiliated with the new study, and an assistant professor of surgery at the University of Pittsburgh and director of the premenopausal breast cancer program at the University of Pittsburgh Medical Center. 
  
 Menon and her colleagues followed 92,834 postmenopausal women for more than three years. At the study’s outset, the women were asked for their heights and weights as well as lifestyle and reproductive histories. To get a better sense of the change in the women’s weight with time, the researchers asked what skirt size each currently wore and what they wore when they were in their 20s. 
  
 PHILIPPE HUGUEN / AFP/Getty Images An increase of one size every 10 years led to a 33 percent rise in the risk of postmenopausal breast cancer, researchers found. 
  
 In their final tally of the impact of increasing waist size, the researchers accounted for such factors as a family history of breast and ovarian cancer, pregnancies, smoking and drinking habits, and use of hormone replacement therapy. 
  
 During the course of the study 1,090 women, or 1.2 percent, developed breast cancer. 
  
 “A nice aspect of this study is that it looked at skirt size, which hasn’t been looked at before,” said Dr. Kala Visvanathan, an associate professor of cancer epidemiology and medical oncology at the Johns Hopkins Bloomberg School of Public Health and director of the cancer genetics and prevention service at Hopkins’ Sidney Kimmel Comprehensive Cancer Center. “It’s a nice measure for women, something they can easily relate to.” 
  
 Further, the study puts an emphasis on weight change, Visvanathan said. “Women sometimes think they are overweight and there’s no point in trying to lose at this point,” she added. “But this may mean that a decrease in weight could be protective.” 
  
 Although a correlation has been made between weight gain and increased cancer risk, no one knows exactly how fat might be contributing. 
  
 “The mechanism between increased abdominal fat and increased breast cancer risk needs to be better understood,” Menon said. “Mechanisms put forward include sex steroid hormones, insulin resistance and chronic inflammation. Previous studies suggest that body fat around the waist is metabolically more active than fat tissue elsewhere in the body.” 
  
 Experts said that older women may not need to get all the way back to the weight they were in their 20s. 
  
 “I think it’s almost too much to ask women in their 60s to be the same weight they were in their 20s,” McGuire said. “We’ve gotten to the point where we just ask them to try to maintain the weight they were at at menopause. 
  
 “But for younger women, they need to look at trying to maintain the same weight fairly steadily throughout their lives. And if they are heavy now, they should try to lose the weight before menopause, when it is so much more difficult to lose weight.” 
  
 Linda Carroll is a regular contributor to NBCNews.com and TODAY.com. She is co-author of "The Concussion Crisis: Anatomy of a Silent Epidemic” and the recently released “Duel for the Crown: Affirmed, Alydar, and Racing’s Greatest Rivalry” ||||| Image copyright SPL 
  
 Going up several skirt sizes in midlife could be a warning sign of increased cancer risk, research suggests. 
  
 Women who went up a skirt size every decade after their mid-20s had a 33% greater risk of breast cancer after the menopause, say researchers at University College London. 
  
 Watching your skirt size from your mid-20s onwards could be a simple way to track weight gain, they told BMJ Open. 
  
 Obesity is a known risk factor for cancer, particularly midriff fat. 
  
 Women are more likely to remember their skirt size when they were younger than their BMI Simon Vincent, Breakthrough Breast Cancer 
  
 Prof Usha Menon of the Department of Women's Cancer, who led the study, told BBC News: "If skirt size could be confirmed by others as a good predictor of breast cancer risk in older women, this would be a very simple and easy way to monitor weight gain." 
  
 Lifestyle factors 
  
 The study tracked more than 90,000 women in their 50s and 60s living in England. 
  
 During the three-year follow-up period, 1,090 women developed breast cancer. 
  
 The researchers found that a unit increase in UK skirt size every 10 years (for example from 12 to 14) between 25 and post-menopausal age was linked to a 33% increased risk of breast cancer. 
  
 Going up two skirt sizes in the same period was associated with a 77% greater risk, they report. 
  
 Commenting on the research, Simon Vincent of Breakthrough Breast Cancer said: "We know that 40% of breast cancers could be prevented by changes to lifestyle such as being regularly active and maintaining a healthy weight. 
  
 "This study highlights an easy way to monitor your weight gain over time. Women are more likely to remember their skirt size when they were younger than their BMI." 
  
 Limitations 
  
 The researchers said the study had some limitations - it relied on women being able to accurately recall their skirt size in their 20s. 
  
 But if the findings are confirmed, it could give women a simple and easy-to-understand message about the risks of obesity. 
  
 Tom Stansfeld of Cancer Research UK said the study could be unreliable as dress sizes had changed over the years and it relied on a woman being able to remember her skirt size several decades earlier. 
  
 "Evidence tells us the most important things you can do to reduce breast cancer risk, especially after the menopause, is to keep a healthy weight, be physically active as often as you can, and cut down on alcohol," he said. 
  
 "Keeping a healthy weight is important to help reduce breast cancer risk after the menopause, and looking at skirt sizes to help women understand this is interesting, but knowing if you're overweight is more important." |||||

Obesity, especially when fat is concentrated in one's middle, is a known risk factor for cancer. But gaining weight throughout one's life has just been found to be another—at least when it comes to women and postmenopausal breast cancer. Researchers found that going up a size every decade from one's 20s to 60s increases the risk of postmenopausal breast cancer by 33%, while going up two sizes a decade increases that risk by 77%, reports Today. The vast study published this week in the journal BMJ Open followed 90,000 women in their 50s and 60s in England, though it comes with a few shortcomings, such as women possibly not being able to accurately recall their skirt size from several decades ago, not to mention those sizes themselves changing over time. But researchers say that tracking sizes could help, and it's a good reminder that a healthy lifestyle—including a nutritious diet, regular exercise, and moderate drinking—can have a protective effect against cancer, reports the BBC. (Even exposure to artificial light at night may play a role in cancer.)