News Headlines: Obesity and Weight Loss
Late-Night Snacking May Affect Sleep Quality
Study Shows How to Lose Weight Without Losing Bone
Study Finds Connection Between Obesity and Depression
Overweight Men at Risk for Hip and Knee OA
Obesity Linked to Increased Risk for Dementia
Obesity Raises Risk of Surgical Complications
Dementia Risk in Old Age Linked to Belly Size in Midlife
Counseling Beats Web-based Support for Dieters
Anxiety and Depression Linked to Smoking and Obesity
Obesity Impedes Recovery from Total Knee Replacement
Artificial Sweeteners Linked to Weight Gain
Obesity Is Bad for Bone Health, New Study Finds
Tweaking ‘Skinny Gene’ May Make You Thinner and Healthier
Weight-Loss Surgery Reduces Risk of Death
Late-Night Snacking May Affect Sleep Quality
New research shows that eating too much or too close to bedtime may do more than lead to weight gain – it may also disrupt your sleep.
The study, out of Federal University of Sao Paulo, in
According to the results, positive and statistically significant correlations were found between total calorie intake and late-night snacking and awakenings during sleep.
While previous studies have shown that the distribution of food intake is capable of modifying hormonal and metabolic patterns during sleep, studies of the influence of food intake distribution on sleep patterns are scarce. This study, which analyzed the influence of energy intake on the sleep patterns in healthy subjects, concluded that total energy intake and late-night snack energy intake may increase sleep fragmentation in healthy subjects, and that sleep restriction in turn may affect nutritional and metabolic balance. However, further studies are needed to better understand the association.
The study was presented at the the 22nd Annual Meeting of the Associated Professional Sleep Societies (APSS). 6/12/08
Study Shows How to Lose Weight Without Losing Bone
A higher-protein diet that emphasizes lean meats and low-fat dairy foods as sources of protein and calcium can mean weight loss without bone loss, a new study shows.
Scientists at the University of Illinois (U of I) and Pennsylvania State University recruited and randomized 130 middle-aged, overweight people to follow either a higher-protein weight-loss diet or a conventional higher-carbohydrate weight-loss diet for four months followed by eight months of weight maintenance.
Bone mineral content and density were measured with DXA scans of the whole body, lumbar spine, and hip at the beginning of the study, at four months, at eight months, and at the end of the 12-month period.
"In the higher-protein group, bone density remained fairly stable, but bone health declined over time in the group that followed the conventional higher-carbohydrate diet,” says Matthew Thorpe, a medical scholars student at U of I and primary author of the study.
"Essentially we substituted lean meats and low-fat milk, cheese, yogurt, etc., for some of the high-carbohydrate foods in the food-pyramid diet,” says Ellen Evans, a member of the U of I Division of Nutritional Sciences. “Participants also ate five servings of vegetables and two to three servings of fruit each day."
The finding, published in this month's Journal of Nutrition, is important because treating obesity – while important for minimizing the risk of many health problems – often increases the risk for osteoporosis. “Many people lose bone mass when they lose weight," says Evans. 6/9/08
Study Finds Connection Between Obesity and Depression
If arthritis is making you feel down, be careful not to use food to boost your mood. A new study shows that people who are depressed are likely to become obese and that, conversely, people who are obese are likely to become depressed.
To understand the potential links between obesity and depression, researchers led by Sarah M. Markowitz, of
People who are obese may be more likely to become depressed because they perceive themselves as in poor health and are dissatisfied with their appearance. This occurrence was particularly prevalent among women and those of high socio-economic status, the study found.
People who are depressed may be more likely to become obese because of physiological changes in their hormone and immune systems that occur in depression. Also, they have more difficulty taking good care of themselves because of symptoms and consequences of depression, such as difficulty adhering to fitness regiments, overeating, and having negative thoughts.
Treatments such as exercise and stress reduction can help to manage both obesity and depression at the same time, say the authors. Potentially, dieting, which can worsen mood, and antidepressants, which can cause weight gain, should be minimized.
"The treatment of depression and obesity should be integrated," the authors conclude. "This way, healthcare providers are working together to treat both conditions, rather than each in isolation."
The review was published in Clinical Psychology: Science and Practice.
Eating Frequency Not Key to Weight Loss
While people trying to lose weight are often advised to eat several small meals a day or three small meals plus snacks, a new Australian study suggests that’s not always the best strategy. What and how much you eat matters more than when and how often, it found.
The study – which involved 179 obese men and women who were all on a reduced-calorie diet, but with different eating patterns – found no difference in weight, waist measurement, body fatness or blood sugar levels between people who ate three meals a day, and those who ate three meals and three snacks while trying to lose weight.
There seems to be little benefit to changing how often or how regularly you eat if you're trying to lose weight, says dietitian and lead author Michelle Palmer. Many people find it hard enough to stick to a healthy eating plan to lose weight, let alone worrying about any suggested benefits of snacking or not snacking.
Palmer says if you choose to snack, it’s important to choose snacks wisely “Manufactured snack foods can be high in saturated fat, salt, sugar and [calories], but low in nutrients like vitamins and minerals, and fiber - which keeps us full,” she says.
Ms Palmer recommends planning snacks with small portions in mind. And she said time-pressed nibblers should consider nutritious, quick and filling snacks like raisin toast, a handful of unsalted nuts, crackers with low-fat cheese, a cup of yogurt or a piece of fruit, or a bowl of cereal with reduced-fat milk. 5/29/08
For good advice on losing weight, see Arthritis Today's Weight-Loss Guide.
Overweight Men at Risk for Hip and Knee OA
Men who are overweight or obese are much more likely need a hip replacement for osteoarthritis than men who are of normal weight, according to new research published online ahead of print in Annals of the Rheumatic Diseases.
Although overweight and obesity are known to be risk factors for knee OA, this is the first study to show that being overweight is a risk factor for hip OA in men but now women, say the study’s authors.
Researchers compared the body mass indexes of 1,473 Icelandic people who had undergone hip or knee replacement with those of 1,103 people who had not had joint replacement surgery. All were born between 1910 and 1939.
They found women who were overweight – having a body mass index (BMI) greater than 25 – were no more likely to have had a hip replacement than women of normal weight, but men were. Men who were obese – having a BMD greater than 30 – were 70 percent more likely to have had hip replacement surgery.
People of both sexes who were overweight were much more likely to have had knee replacement surgery and the more overweight they were the more likely it was. Men who were obese were five times more likely to have had a replacement knee and women four times more likely.
“The study supports a positive association between high BMI and total knee replacement in both sexes,” say the authors. “But for total hip replacement the association with BMI seems to be weaker, and possibly negligible for women.” 5/29/08
For good advices on losing weight, see Arthritis Today's Weight-Loss Guide
Learn about the different treatments for OA.
Obesity Linked to Increased Risk for Dementia
A new study offers yet another compelling reason to maintain a healthy weight: to maintain a healthy brain.
In an analysis of published obesity and dementia prospective follow-up studies over the past two decades, the researchers at Johns Hopkins Bloomberg School of Public Health found a consistent relationship between the two diseases.
“Our analysis of the data shows a clear association between obesity and an increased risk for dementia and several clinical subtypes of the disease,” said Youfa Wang, MD, PhD, senior author of the study and associate professor with the Bloomberg School s Center for Human Nutrition. “Subjects with a healthy body mass index (BMI) and waist circumference saw a decreased risk for dementia than their counterparts with an elevated BMI or waist circumference.”
Wang adds that preventing or treating obesity at a younger age could play a major role in reducing the number of dementia patients in this country by up to 20 percent.
Based on a pooled analysis of their findings from seven of the studies, baseline obesity compared to normal weight increased the risk of Alzheimer’s disease by 80 percent on average. The team further concluded that being underweight also increases the risk of dementia and its subtypes.
“Currently, Alzheimer’s disease is the eighth leading cause of death among the elderly population in the United States. While more studies are needed to determine optimal weight and biological mechanisms associated with obesity and dementia, these findings could potentially decrease the number of people diagnosed with dementia and lead to an overall better quality of life,” says lead researcher May A. Beydoun, a former postdoctoral research fellow at Johns Hopkins. 5/15/08
Obesity Raises Risk of Surgical Complications
Obesity not only increases your risk of osteoarthritis or even your chances of needing total hip replacement if you have OA. For people who have already had hip replacement, being obese can increase the risk of complications should they need to have the hip surgery revised, according to a new study published in Arthritis & Rheumatism.
The study focused on all patients who underwent a total hip replacement revision at Geneva University Hospitals between 1966 and 2006. Based on height and weight data obtained just before surgery, 25 percent of the patients were defined as obese with a body mass index of 30 or more.
At follow up, obese patients had four times the rate of complications – including infection and dislocation – compared to non-obese patients. Among the heaviest patients – those with a BMI of 35 or higher – the risk of complications was 10.9 times higher than for non-obese patients, after adjusting for age, sex, and preoperative health status.
“Surgeons, patients, and referring physicians should be aware of an increased risk in this patient group,” says Anne Lübbeke, the study’s lead author. “Further studies are necessary to evaluate whether changes in medical preparation, surgical technique, and implant choice can help reduce the adverse event rate in obese patients undergoing revision [total hip replacement].”
Dementia Risk in Old Age Linked To Belly Size in Midlife
A study published in the current issue of the journal Neurology offers a new warning for middle-aged people who tend to accumulate fat around their mid-sections: Excessive belly fat now could increase your risk of dementia later. The study, led by Kaiser Permanente research scientist Rachel Whitmer, PhD, further showed that being overweight or obese and carrying excessive belly fat increased the risk higher – even doubling or tripling the risk.
While previous research has linked excessive abdominal fat in middle age to an increased risk of diabetes and heart disease, this new study – based on the records of 6,583 Kaiser Permanente health plan members who had their abdominal fat measured between 1964 and 1973 when they were 40 to 45 years old – is the first study to link abdominal fat in the middle-adult years to the development of dementia decades later.
The researchers don’t know why belly fat would increase dementia risk, but say it could be an indicator of long-term disruption of metabolism that affects brain function. Further research is needed to understand the connection and how to address the problem.
While we have little, if any control, over where our body carries excess fat, the study stresses the importance of achieving and maintaining a healthy weight to help reduce excessive belly fat and avoid upping the risk due to overweight or obesity. 3/28/08
Counseling Beats Web-based Support for Dieters
When it comes to losing weight and keeping it off, a new study shows that you’ll likely have better results working one-on-one with a counselor than going it alone or seeking support through a weight-loss Web site.
In the study, published March 12 in the Journal of the American Medical Association, researchers from Johns Hopkins and seven other institutions compared different interventions aimed at preventing weight regain among 1,032 volunteers who had recently lost, on average, about 19 pounds each.
The researchers tracked the volunteers, separated into three groups, over two and a half years. One group received regular, personal contact from trained weight-loss counselors. A second group was given access to a custom-built weight-loss Web site loaded with information and tools to track weight, record food diaries and monitor physical activity levels. A third group received some printed information with diet and lifestyle recommendations at the beginning of the study and met briefly with a counselor halfway through.
By the end of the study, most of the volunteers had gained some weight back; however, the least gain was seen in the personal-contact group, who gained an average of nine pounds, compared to the other groups’ 12-pound gain.
Although these differences were modest, the researchers note even small changes in weight can have big effects on health. They speculate that being personally accountable to a caring counselor could be an important motivator for people to maintain healthy eating habits.
Anxiety and Depression Linked to Smoking and Obesity
People who suffer from depression or anxiety are much more likely to be obese and to smoke — both major risk factors for chronic disease — according to a large nationwide study.
The study, in the March/April issue of the journal General Hospital Psychiatry, compiled data from more than 200,000 adults who participated in the Behavioral Risk Factor Surveillance System, a large telephone survey that monitors the prevalence of key health behaviors.
About 8.7 percent of the respondents had current depression, 15.7 percent had a previous depression diagnosis and 11.3 percent had had an anxiety diagnosis at some time.
People with current depression or a previous diagnosis of depression were 60 percent more likely to be obese and twice as likely to smoke as those who were not depressed, the research found. Those with an anxiety disorder were 30 percent more likely to be obese and twice as likely to smoke as those without anxiety were. The study also said that those with depression and anxiety were more likely to be physically inactive and to be binge or heavy drinkers.
Because chronic diseases are risk factors for depression, the study’s authors say the health care system must be attuned to recognizing and treating the depression that often coexists with chronic diseases. 3/10/08
Obesity Impedes Recovery from Total Knee Replacement
If you’re planning knee replacement, but could stand to lose a little – or maybe a lot of – weight, a new study offers added reason to lose those pounds. The study, presented at the 75th Annual Meeting of the
Comparing data from 309 patients (400 knee replacements) who underwent total knee
“For anyone considering knee replacement surgery, recovery time is always an important consideration,” Geoffrey Westrich, MD, lead author of the study and an associate professor of orthopaedic surgery at HSS. “Patients often ask me if their pain is going to be relieved and if they will have better range of motion. Our findings will help set more realistic expectations for heavy patients. They need to be counseled that their weight will likely impede their recovery.”
Artificial Sweeteners Linked to Weight Gain
New research shows that using artificially sweetened foods and drinks to control or lose weight may backfire, causing you to gain more than you would have consuming their sugar-sweetened, higher calorie counterparts.
In studies of laboratory rats, researchers at Perdue University’s Ingestive Behavior Research Center reported that those consuming saccharin-sweetened yogurt consumed more calories, gained more weight and put on more body fat than rats fed yogurt sweetened with glucose.
The researchers surmised that by breaking the connection between a sweet sensation and high-calorie food, the use of saccharin changes the body’s ability to regulate intake. That change depends on experience. Problems with self-regulation might explain in part why obesity has risen in parallel with the use of artificial sweeteners. It also might explain why scientific consensus on human use of artificial sweeteners is inconclusive, with various studies finding evidence of weight loss, weight gain or little effect. Because people may have different experiences with artificial and natural sweeteners, human studies that don’t take into account prior consumption may produce a variety of outcomes.
Why would a sugar substitute backfire? Because sweet foods provide a “salient orosensory stimulus” that strongly predicts someone is about to take in a lot of calories, according to the authors. Ingestive and digestive reflexes gear up for that intake but when false sweetness isn’t followed by lots of calories, the system gets confused. Thus, people may eat more or expend less energy than they otherwise would.
The findings appear in the February issue of Behavioral Neuroscience. 2/13/08
Obesity Is Bad for Bone Health, New Stidy Finds
A new study by researchers at the
Researchers conducted advanced three-dimensional bone scans on 115 women ages 18 and 19 with normal (less than 32 percent) and high (greater than 32 percent) body fat. After adjusting for differences in muscle mass surrounding the bone, the researchers found that the bones of participants with high body fat were 8 to 9 percent weaker than those of participants with normal body fat.
The new findings contradict conventional thinking that body fat is protective of bones. Previous studies on bone health and obesity used a two-dimensional bone densitometer that is commonly used in osteoporosis screenings, says study co-author Richard D. Lewis. He explains that a notable shortcoming of the bone densitometer is that it does not take into account bone shape and geometry, which have a substantial influence on bone strength.
Lewis says the exact mechanisms by which excess fat hinders bone strength are unclear, but studies of obese rats show that they produce more fat cells in the bone marrow and fewer bone cells. The new study was published in the November issue of the American Journal of Clinical Nutrition.
Excess Body Fat Causes Cancer
You know that excess weight places stress on arthritic joints and can even increase your risk of some forms of arthritis. Now a landmark report shows that excess body fat may be one of the greatest risk factor for many forms of cancer.
The World Cancer Research Fund (WCRF) report, based on the findings of 7,000 individual studies, is the most comprehensive ever published on the link between cancer and diet, physical activity and weight.
The study’s key finding is that maintaining a healthy weight (a BMI of 20-25) is one of the most important things you can do to prevent cancer. The number of types of cancer where there is "convincing" evidence that body fat is a cause has risen from one to six, including colorectal cancer and post-menopausal breast cancer, since the last WCRF report was published in 1997.
Other key findings:
- Convincing evidence that processed meats, including ham and bacon, increase the risk of colorectal cancer.
- Convincing evidence that breastfeeding protects mothers against breast cancer; probable evidence that is also protects the child against obesity later in life.
- Strong evidence that alcohol is a cause of cancer.
Tweaking 'Skinny Gene' May Make You Thinner and Healthier
New research suggests that by turning on a skinny gene in your body your doctor may one day be able help you fit into those skinny jeans in your closet – while reducing the stress of excess weight on arthritis joints and preventing obesity-related health problems.
For more than half a century, scientists have been aware of the existence of the adipose gene, which influences whether the body accumulates or burns fat. However, they have known little about the gene works. Now, a study published in the journal Cell Metabolism offers clues. In the five year-study of worms, fruit flies and mice, scientists found that the more the adipose gene was stimulated, the thinner the subjects became. When they turned the gene down, the subjects got fatter. The mice also developed type 2 diabetes.
While the research so far has been limited to animals, the scientists believe their findings should extend to humans.
Weight-Loss Surgery Reduces Risk of Death
Two studies published in the August 23 issue of the New England Journal of Medicine confirm that weight-loss surgery does far more than reduce weight. It also reduces the risk of death. In the larger of the two, a 14-year study of 15,850 obese people – half of whom had gastric bypass surgery to reduce weight – researchers in Utah found that deaths due to coronary heart disease were 56 percent lower in the surgery group and that deaths due to cancer and diabetes were 60 and 92 percent lower, respectively, compared to the group that did not have surgery.
In the second study, Swedish researchers who followed 4,000 severely obese people -- half of whom had a gastric bypass or banding procedure for weight loss -- found that those who had surgery were 29 percent less likely to die during follow up than those who had not had surgery.
Researchers believe the weight loss resulting from the surgeries – rather than any aspect of the surgery itself – were responsible for the decreased risk of death.
To learn more about weight loss surgery, read this Arthritis Today special report.
