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Published on Leave a comment on Overweight and Obesity Is Associated With Reduced Blood Flow In the Brain

There is another great reason to try to lose weight if you are overweight or obese - being overweight or obese lowers blood flow to the brain in older adults. Yikes! However, one bit of good news from a study of 495 adults (average age 69) was that increased physical activity (brisk walks count!) can reduce or eliminate this association.

This could help explain why obesity increases the risk for a number of conditions as a person gets older, such as heart disease, dementia, and Alzheimer's disease.

The study was part of the Irish Longitudinal Study on Ageing. The average BMI (body mass index) was 28, which is considered overweight. One finding was that each 1 cm increase in waist circumference was associated with the same reduction of brain (cerebral) blood flow as 1 year of advancing age. (Yes, brain volume and blood flow typically diminish with age in older adults. So you want to prevent it as much as possible.)

The study found that higher levels of physical activity can reduce or remove this association of overweight & obesity and reduced brain blood flow. So if it's not possible to lose weight - then get really physically active!

How much exercise is beneficial? The researchers recommend at least 1.5 to 2 hours per day of "being active", that is, doing activities that require "moderate" effort - this means breathing somewhat harder than normal (e.g. brisk walking, cycling at a regular pace, carrying light loads). Equally beneficial is to get some "vigorous activity" which results in breathing much higher than normal (e.g., digging, aerobics, fast cycling, carrying heavy loads). But any and all movement is good!

Medical Xpress: Researchers find obesity linked to reduced blood flow to the brain

A new study from scientists at The Irish Longitudinal Study on Aging (TILDA) at Trinity College Dublin reveals important findings, indicating that being overweight or obese significantly reduces blood flow in the brain. The study also shows that increased physical activity can positively modify, or even negate, this reduction in brain blood flow. ...continue reading "Overweight and Obesity Is Associated With Reduced Blood Flow In the Brain"

Published on Leave a comment on Being Overweight Is Higher Risk For Severe Coronavirus Infections

Two big risk factors are emerging over who will develop severe COVID-19 infections that lead to hospitalizations and needing intensive care. A number of studies throughout the world are reporting that the main risk factor in persons under 60 years is being significantly overweight, especially obesity, and the other risk factor is being over 65 years of age.

What is significantly overweight? A body mass index (BMI) of 30 or more is considered obese - probably 40 pounds or more overweight. For example, a 5 ft 5 inch person weighing 181 pounds or more, or a 5 ft 10 inch person 210 pounds or more. [see BMI chart]

Two studies of New York City hospital patients had similar findings. Doctors at NYU Langone Health (Lighter et al) found that overweight patients who were under age 60 were twice as likely to be hospitalized as their thinner peers, while those who were obese were three times as likely to need intensive care, the study found. And this is in patients who didn't have any other diseases or conditions - they were healthy, but overweight. The medical thinking is that this may because obesity is a state of chronic inflammation.

The scary part is that the US has a very high obesity rate - with the NYU researcher Jennifer Lighter pointing out that nearly 40% of adults in the US are obese with a body mass index (BMI) of 30 or more!

A French study found that a key finding was that those with a BMI of greater than 35 had more than sevenfold increased risk of requiring mechanical ventilation (compared to those with a BMI of less than 25). Studies are also finding that disease severity increased with increasing BMI.

Interestingly, obesity wasn't a predictor of severe disease leading to hospital admission or the ICU (intensive care unit) in those over the age of 60 years. But in those younger than 60 years, it was.

Excerpts from Medscape: Obesity Link to Severe COVID-19, Especially in the Under 60s

It is becoming increasingly clear that obesity is one of the biggest risk factors for severe COVID-19 disease, particularly among younger patients.  ...continue reading "Being Overweight Is Higher Risk For Severe Coronavirus Infections"

Published on Leave a comment on Obesity Associated With Poorer Sperm Quality

Another problem for overweight or obese men: an increased risk of poor sperm quality. Researchers in India found that compared to normal weight men, obesity was associated with lower sperm count, lower volume of semen, lower sperm concentration, poor sperm motility (the movement of sperm), as well as sperm defects. There is some evidence (from other studies and the researchers own work) that there is improvement in sperm quality with weight loss.

The researchers pointed out that other studies have shown that "paternal obesity at conception had deleterious effects on embryo health, implantation, pregnancy, and live birth rates." And that poor sperm quality is a cause of infertility. So.... what do the researchers recommend? Weight loss and exercise, and perhaps bariatric surgery, for obese men having fertility problems due to poor sperm quality. From Medical Xpress: 

As men's weight rises, sperm health may fall

A widening waistline may make for shrinking numbers of sperm, new research suggests. Indian scientists studied more than 1,200 men and found that too much extra weight was linked to a lower volume of semen, a lower sperm count and lower sperm concentration. In addition, sperm motility (the ability to move quickly through the female reproductive tract) was poor. The sperm had other defects as well, the researchers added. Poor sperm quality can lower fertility and the chances of conception.

"It's known that obese women take longer to conceive," said lead researcher Dr. Gottumukkala Achyuta Rama Raju, from the Center for Assisted Reproduction at the Krishna IVF Clinic, in Visakhapatnam. "This study proves that obese men are also a cause for delay in conception," he added.

But in continuing research, the study team is looking to see if losing weight will improve the quality of sperm. Although that study is still in progress, early signs look good that sperm quality improves as men lose weight, Rama Raju said. Recent reports have found that extreme weight loss after bariatric surgery reversed some of the sperm decline, he said.

For the study, Rama Raju and his colleagues used computer-aided sperm analysis to assess the sperm of 1,285 men. Obese men, they found, had fewer sperm, a lower concentration of sperm and inability of the sperm to move at a normal speed, compared with the sperm of men of normal weight. Moreover, the sperm of obese men had more defects than other sperm. These defects included defects in the head of the sperm, such as thin heads and pear-shaped heads.  [Original study.]

 Human sperm. Credit: Wikipedia

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Yup, according to a new mega-study, being overweight or obese is linked to higher risk of dying prematurely than being normal weight.  And the more you weigh, the greater the risk. This mega-study that looked at data from many studies and countries, also found that being underweight is linked to a higher risk of premature death. What's the best weight to be? A BMI of 22.5-<25 kg/m2 is considered a healthy weight range, and had the lowest mortality risk in the study. Being overweight was linked to higher rates of death from "all causes", and also from 4 major causes: coronary heart disease, stroke, respiratory disease, and cancer.

However, note that while other studies also agree that being underweight or obese increases the rate of dying prematurely, there is still some debate over whether being just overweight with BMI 25–<30 kg/m2 , really has a higher risk of dying prematurely. This was pointed out in the accompanying editorial in the journal Lancet (but not mentioned below). From Science Daily:

As overweight and obesity increase, so does risk of dying prematurely: Major study

Being overweight or obese is associated with a higher risk of dying prematurely than being normal weight -- and the risk increases with additional pounds, according to a large international collaborative study led by researchers at the Harvard T.H. Chan School of Public Health and the University of Cambridge, UK. The findings contradict recent reports that suggest a survival advantage to being overweight -- the so-called "obesity paradox."

The deleterious effects of excess body weight on chronic disease have been well documented. Recent studies suggesting otherwise have resulted in confusion among the public about what is a healthy weight. According to the authors of the new study, those prior studies had serious methodological limitations. One common problem is called reverse causation, in which a low body weight is the result of underlying or preclinical illness rather than the cause. Another problem is confounding by smoking because smokers tend to weigh less than nonsmokers but have much higher mortality rates.....Hu stressed that doctors should continue to counsel patients regarding the deleterious effects of excess body weight, which include a higher risk of diabetes, cardiovascular disease, and cancer.

For the new study, consortium researchers looked at data from more than 10.6 million participants from 239 large studies, conducted between 1970 and 2015, in 32 countries. A combined 1.6 million deaths were recorded across these studies, in which participants were followed for an average of 14 years. For the primary analyses, to address potential biases caused by smoking and preexisting diseases, the researchers excluded participants who were current or former smokers, those who had chronic diseases at the beginning of the study, and any who died in the first five years of follow-up, so that the group they analyzed included 4 million adults. They looked at participants' body mass index (BMI) -- an indicator of body fat calculated by dividing a person's weight in kilograms by their height in meters squared (kg/m2).

The results showed that participants with BMI of 22.5-<25 kg/m2 (considered a healthy weight range) had the lowest mortality risk during the time they were followed. The risk of mortality increased significantly throughout the overweight range: a BMI of 25-<27.5 kg/m2 was associated with a 7% higher risk of mortality; a BMI of 27.5-<30 kg/m2 was associated with a 20% higher risk; a BMI of 30.0-<35.0 kg/m2 was associated with a 45% higher risk; a BMI of 35.0-<40.0 kg/m2 was associated with a 94% higher risk; and a BMI of 40.0-<60.0 kg/m2 was associated with a nearly three-fold risk. Every 5 units higher BMI above 25 kg/m2 was associated with about 31% higher risk of premature death. Participants who were underweight also had a higher mortality risk.

Looking at specific causes of death, the study found that, for each 5-unit increase in BMI above 25 kg/m2, the corresponding increases in risk were 49% for cardiovascular mortality, 38% for respiratory disease mortality, and 19% for cancer mortality. Researchers also found that the hazards of excess body weight were greater in younger than in older people and in men than in women.

Published on Leave a comment on Regular Physical Activity Is A Magic Bullet In Preventing Health Problems

A recent editorial in the journal Cardiology calls exercise the "magic bullet" in preventing all sorts of diseases, including cardiovascular disease and diabetes.

From Science Daily: Regular physical activity is 'magic bullet' for pandemics of obesity, cardiovascular disease

In an editorial published in the current issue of Cardiology, professors from the Charles E. Schmidt College of Medicine at Florida Atlantic University have evaluated the totality of evidence and conclude that regular physical activity bears the closest resemblance to a "magic bullet" to combat the worldwide epidemic of obesity and cardiovascular disease.

The statistics on regular physical activity in the United States are bleak; only about 20 percent of Americans (23 percent of men and 18 percent of women) engage in recommended levels of regular physical activity and about 64 percent never do any physical activity. In Europe, the statistics are not much better with only 33 percent who engage in physical activity with some regularity, while 42 percent never do any physical activity.

The authors also point out that physical activity confers important beneficial effects beyond body weight and include blood pressure, cholesterol, triglyceride, diabetes, heart attacks, strokes, colon cancer and possibly even breast and prostate cancers as well as arthritis, mood, energy, sleep and sex life.

Starting in their 30s, Americans and many Europeans tend to gain between 1 and 3 pounds of body weight per year, and by 55, many are between 30 and 50 pounds overweight....The authors note that brisk walking for only 20 minutes a day burns about 700 calories a week, results in a 30 to 40 percent reduced risk of coronary heart disease, and can be performed even by the elderly. They stress that regular physical activity also should include resistance exercise such as lifting weights, which can even be safely performed in the elderly and in patients with heart failure.

Published on Leave a comment on High Obesity Rates in US and Globally

Obesity rates in the US are high! Obesity rates in the US were 35% among men and 40.4% in women in 2013-2014, and extreme obesity (class 3) rates were 5.5% for men and 9.9% for women. Obesity is defined as a body mass index (BMI) 30 or greater (≥30), and extreme obesity or class 3 obesity is a body mass index of 40 or greater (BMI ≥40).

A second study analyzed data from 186 countries and found that global obesity numbers have shot up from 105 million people in 1975 to 641 million in 2014. The senior author Dr. Majid Ezzati of the study said: "Over the past 40 years, we have changed from a world in which underweight prevalence was more than double that of obesity, to one in which more people are obese than underweight."

From Science Daily: Prevalence of obesity in U.S. increases among women, but not men

The prevalence of obesity in 2013- 2014 was 35 percent among men and 40 percent among women, and between 2005 and 2014, there was an increase in prevalence among women, but not men, according to a study appearing in the June 7 issue of JAMA. Between 1980 and 2000, the prevalence of obesity increased significantly among adult men and women in the United States...The analysis included data from 2,638 adult men (average age, 47 years) and 2,817 women (average age, 48 years) from the most recent 2 years (2013-2014) of NHANES and data from 21,013 participants in previous NHANES surveys from 2005 through 2012.

For the years 2013-2014, the overall age-adjusted prevalence of obesity (body mass index [BMI] 30 or greater) was 38 percent; among men, it was 35 percent; and among women, it was 40 percent. The corresponding prevalence of class 3 (BMI 40 or greater) obesity overall was 7.7 percent; among men, it was 5.5 percent; and among women, it was 9.9 percent. 

The authors write that although there has been considerable speculation about the causes of the increases in obesity prevalence, data are lacking to show the causes of these trends, and there are few data to indicate reasons that these trends might accelerate, stop, or slow. "Other studies are needed to determine the reasons for these trends." 

From Medscape: Obesity Now More Common Than Underweight Worldwide

Global obesity numbers have shot up from 105 million people in 1975 to 641 million in 2014, according to the most comprehensive body mass index (BMI) trend analysis to date. Researchers estimate that the age-corrected proportion of men who were obese climbed from 3.2% to 10.8% in that time and the rate among women more than doubled, going from 6.4% to 14.9%. During the same 40-year period, the proportion of men who were underweight globally fell from 13.8% to 8.8% and among women it declined from 14.6% to 9.7%.

Underweight numbers were highest in South Asia in 2014 at 23.4% (95% CI, 17.8%–29.2%) in men and 24% (95% CI, 18.9%–29.3%) in women. Underweight prevalence also stood at more than 12% in women and more than 15% in men in Central and East Africa in 2014, despite some reductions over the 4 decades....Almost half of the world's underweight men (46.2%) and women (41.6%) live in India, the study found.

Polynesia and Micronesia had the highest average BMI in the world. More than 38% of men and over half of women are obese there. The study finds that almost 20% of the world's obese adults (118 million) live in six high-income countries—Australia, Canada, Ireland, New Zealand, the United Kingdom, and the United States. More than a quarter (27.1% or 50 million) of the world's severely obese people also live in these countries. More than one in four severely obese men (27.8%) and 18.3% of severely obese women in the world live in the United States.

Published on Leave a comment on New Report About Harms of Endocrine Disruptors

A report released this week by the Endocrine Society states that the list of health problems that scientists can confidently link to exposure to hormone-disrupting chemicals has grown to include: diabetes, cardiovascular disease, obesity, reproductive and developmental problems, thyroid impairment, certain reproductive cancers, and neurodevelopmental problems such as decreased IQ. This statement (report) is based on the summaries of 1300 studies on endocrine disrupting chemicals (EDCs), and it also adds support to the idea that even minute doses of these chemicals can interfere with the activity of natural hormones, which play a major role in regulating physiology and behavior. The statement also stated that most industrial chemicals released into the environment—numbering in the tens of thousands—have never been tested for endocrine-disrupting potential. EDCs include such common chemicals as bisphenol A (BPA), phthalates, parabens, some pesticides (e.g., atrazine), flame retardants, some persistent organic pollutants, and dioxins.

Where are endocrine disruptors found? People are exposed to chemicals with estrogenic effects in their everyday life, because endocrine disrupting chemicals are found in low doses in thousands of products. Many plastic products, including those advertised as "BPA free", have been found to leach endocrine-disrupting chemicals (the substitute chemicals are no better than BPA, and may be worse). Examples: plastic food containers which then leach into foods, linings of metal beverage, formula, and food cans, soft plastic toys, dental sealants, consumer goods, receipts, personal care products that contain parabens or phthalates (e.g., found in lotions,sunscreens, fragrances), household products (such as cleaning products, vinyl shower curtains) , cars (that new car smell in car interiors), etc. Americans love plastics, but there is a serious human health cost.

NOTE: To minimize EDC exposure - try to avoid plastic food and beverage containers. Instead try to use glass, stainless steel, or ceramics. Eat as many unprocessed and fresh foods as possible. Use cloth shower curtains. Read labels and avoid BPA, phthalates, parabens. Avoid fragrances. Don't use or buy non-stick pans, stain and water-resistant coatings on clothing, furniture and carpets. When buying new furniture, check that it doesn't have added fire retardants.

Of course any public discussion of the harms from endocrine disrupting chemicals, as well as the newly released Endocrine Society report, is drawing sharp criticisms from the chemical industry (especially the American Chemistry Council, the largest trade group for the chemicals industry). Of course. We all know that the lobbying efforts by the chemical industry to suppress and deny the evidence of harm to humans from EDCs has been and will continue to be massive. Sadly, but at this point EDCs are found in almost everyone on earth. More about the report, from Science Daily:

Chemical exposure linked to rising diabetes, obesity risk

Emerging evidence ties endocrine-disrupting chemical (EDC) exposure to two of the biggest public health threats facing society -- diabetes and obesity. EDCs contribute to health problems by mimicking, blocking or otherwise interfering with the body's natural hormones. By hijacking the body's chemical messengers, EDCs can alter the way cells develop and grow. Known EDCs include bisphenol A (BPA) found in food can linings and cash register receipts, phthalates found in plastics and cosmetics, flame retardants and pesticides. The chemicals are so common that nearly every person on Earth has been exposed to one or more.  ...continue reading "New Report About Harms of Endocrine Disruptors"

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Some recent studies looked at aspirin use and cancer and found that consistent use for a number of years (5 to 10 years) lowers the rate of a number of cancers, including colon cancer. However, the longer one takes daily aspirin - then harms start adding up, with a major one being gastrointestinal bleeding. NSAIDs (non-steroidal anti-inflammatory drugs) are also linked to lower rates of various cancers, but harms with long-term use are cardiovascular risks (stroke and heart attack). The first article discusses that many doctors think this lower cancer rate occurs because aspirin and NSAIDs lower inflammation, and as we know, inflammation is linked to cancer.

From Science News: Aspirin reverses obesity cancer risk

Research has shown that a regular dose of aspirin reduces the long-term risk of cancer in those who are overweight in an international study of people with a family history of the disease....They found that being overweight more than doubles the risk of bowel cancer in people with Lynch Syndrome, an inherited genetic disorder which affects genes responsible for detecting and repairing damage in the DNA. Around half of these people develop cancer, mainly in the bowel and womb. However, over the course of a ten year study they found this risk could be counteracted by taking a regular dose of aspirin.

Lots of people struggle with their weight and this suggests the extra cancer risk can be cancelled by taking an aspirin.This research adds to the growing body of evidence which links an increased inflammatory process to an increased risk of cancer. Obesity increases the inflammatory response. One explanation for our findings is that the aspirin may be suppressing that inflammation which opens up new avenues of research into the cause of cancer."

When they were followed up ten years later, 55 had developed bowel cancers and those who were obese were more than twice as likely to develop this cancer -- in fact 2.75 times as likely. Following up on patients who were taking two aspirins a day revealed that their risk was the same whether they were obese or not....What is surprising is that even in people with a genetic predisposition for cancer, obesity is also a driver of the disease. 

The researchers believe the study shows that aspirin is affecting an underlying mechanism which pre-disposes someone to cancer and further study is needed in this area. Since the benefits are occurring before the very early stages of developing a tumour -- known as the adenoma carcinoma sequence -- the effect must be changing the cells which are predisposed to become cancerous in later years.

...continue reading "Aspirin and Cancer"

Published on

One study points out the difficulty of weight loss in overweight adults, because so few actually are able to get down to a normal weight or even lose a mere 5% of body weight (for example. 10 pounds for a 200 pound person or 15 pounds for a 300 pound person). The annual chance of an obese person attaining normal body weight is only 1 in 210 for men and 1 in 124 for women,and the annual chance of obese patients achieving five per cent weight loss was 1 in 12 for men and 1 in 10 for women.  The second study highlights how well weight loss treats "fatty liver" (which is a problem in middle-aged overweight people). Fatty liver or nonalcoholic steatohepatitis (NASH), which affects 2 to 5 percent of Americans, can be severe and can lead to cirrhosis, in which the liver is permanently damaged and scarred and no longer able to work properly.

After reading scientific studies nonstop for the last few years, it seems that the best, easiest way to lose weight is to have lifestyle changes rather than focusing just on a "weight-loss diet": increase activity levels (yes, walking counts) and switch to a more plant based diet or Mediterranean diet (lots of fruits, vegetables, whole grains, legumes, seeds, nuts, olive oil, some fish each week) and decrease the amount of typical Western style diet (highly processed foods. lots of meat and coldcuts, lots of fat, fast foods, soda). Try to only eat within 12 hours each day (for example, 8am to 8pm) and don't eat the other 12 hours. And of course eat fewer calories (it should be easier  to do if you substitute fruits and vegetables for high calorie processed foods such as ice cream, french fries, and sweets). And yes, of course it's really hard to lose weight, but the health benefits of weight loss are enormous. From Medical Xpress:

Low chance of recovering normal body weight highlights need for obesity prevention

The chance of an obese person attaining normal body weight is 1 in 210 for men and 1 in 124 for women, increasing to 1 in 1,290 for men and 1 in 677 for women with severe obesity, according to a study of UK health records led by King's College London. The findings, published in the American Journal of Public Health, suggest that current weight management programmes focused on dieting and exercise are not effective in tackling obesity at population level.The research, funded by the National Institute for Health Research (NIHR), tracked the weight of 278,982 participants (129,194 men and 149,788) women using electronic health records from 2004 to 2014.

The annual chance of obese patients achieving five per cent weight loss was 1 in 12 for men and 1 in 10 for women. For those people who achieved five per cent weight loss, 53 per cent regained this weight within two years and 78 percent had regained the weight within five years.

Overall, only 1,283 men and 2,245 women with a BMI of 30-35 reached their normal body weight, equivalent to an annual probability of 1 in 210 for men and 1 in 124 for women; for those with a BMI above 40, the odds increased to 1 in 1,290 for men and 1 in 677 for women with severe obesity. Weight cycling, with both increases and decreases in body weight, was also observed in more than a third of patients. The study concludes that current obesity treatments are failing to achieve sustained weight loss for the majority of obese patients.

Dr Alison Fildes, first author from the Division of Health and Social Care Research at King's College London (and now based at UCL), said: 'Losing 5 to 10 per cent of your body weight has been shown to have meaningful health benefits and is often recommended as a weight loss target..... More importantly, priority needs to be placed on preventing weight gain in the first place.'

From Medical Xpress:  Weight loss for a healthy liver

Weight loss through both lifestyle modification and bariatric surgery can significantly reduce features of nonalcoholic steatohepatitis (NASH), a disease characterized by fat in the liver, according to two new studies published in Gastroenterology..."we most commonly see this condition in patients who are middle-aged and overweight or obese," said Giulio Marchesini, MD, from University of Bologna, Italy, and lead author of an editorial summarizing these two studies. "These two large prospective cohort studies strengthen the evidence that, no matter how you lose weight, weight loss improves liver health. Both bariatric surgery for morbidly obese patients or lifestyle modifications are viable options."

Lifestyle modifications: Eduardo Vilar-Gomez and colleagues from Cuba report in Gastroenterology that a weight reduction of 10 percent or more, induced by a comprehensive lifestyle program, is necessary to bring about NASH resolution and reverse scarring of the liver in overweight and obese patients. To a lesser degree, modest weight loss (7 to 10 percent) reduced disease severity in certain subsets of patients, including male patients and those without diabetes. Conversely, 93 percent of the patients with little or no weight reduction (less than 5 percent) experienced worsening of liver scarring....While promising, less than 50 percent of patients achieved the necessary weight loss goal of 7 to 10 percent, providing a stark reminder of the sustainability of weight loss interventions.

Bariatric surgery: For appropriate morbidly obese patients with NASH who have previously failed to lose weight through lifestyle modifications, bariatric surgery may be considered. In the second Gastroenterology study, Guillaume Lassailly and colleagues from France report that, one year after bariatric surgery, NASH had disappeared from 85 percent of patients and reduced the pathologic features of the disease after 1 year of follow-up. NASH disappeared from a higher proportion of patients with mild NASH before surgery (94 percent) than severe NASH (70 percent). More studies are needed to determine the long-term effects of bariatric surgeryin morbidly or severely obese patients with NASH.

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Again, more research finding that being overweight or obese is associated with an increased risk of breast cancer - specifically higher risk of invasive breast cancer in postmenopausal women. They found that the heavier the woman, the higher the risk, but the risk did not vary with hormone therapy use or race and ethnicity. From Medical Xpress:

Obesity associated with increased breast cancer risk in postmenopausal women

An analysis of extended follow-up data from the Women's Health Initiative clinical trials suggests that postmenopausal women who were overweight and obese had an increased risk of invasive breast cancer compared to women of normal weight, according to an article published online by JAMA Oncology. Obesity is a major public health problem in the United States and obesity has been associated with breast cancer risk in observational studies, systematic reviews and meta-analyses.

The Women's Health Initiative (WHI) protocol measured height and weight, baseline and annual or biennial mammograms, and breast cancer in 67,142 postmenopausal women enrolled from 1993 to 1998 with a median of 13 years of follow-up. There were 3,388 invasive breast cancers. Analysis by the authors found:

  • Women who were overweight (body mass index [BMI] 25 to < 30); obese, grade 1 (BMI 30 to < 35); and obese, grade 2 plus 3 (BMI > 35) had an increased risk of invasive breast cancer compared to women of normal weight (BMI < 25)
  • The risk was greatest for women with a BMI greater than 35; those women had a 58 percent increased risk of invasive breast cancer compared with women of normal weight (BMI < 25)....
  • Obesity was associated with markers of poor prognosis; women with a BMI greater than 35 were more likely to have large tumors, evidence of lymph node involvement and poorly differentiated tumors
  • Women with a baseline BMI of less than 25 who gained more than 5 percent of body weight during the follow-up period had an increased risk of breast cancer....