Scientists may have discovered a way of identifying dieters who are prone to piling the pounds back on after weight loss. A study at Maastricht University’s Department of Human Biology found a link between a gene involved in regulating blood pressure and post-diet weight gain in women. Women who regained weight after slimming had a high change in the concentration of a particular protein in their blood during dieting, research showed. Researchers now hope to develop a test to indicate how prone people are to yo-yo dieting.
Edwin Mariman, professor of functional genetics at Maastricht, said: “It was a surprising discovery, because until now there has been no clear link between this protein and obesity. “We do not yet have an explanation for the results, but it does appear that it should be possible within a few years to use this finding to develop a test to show who is at high risk of putting weight back on after a diet.”
Hospitals already conduct tests for the protein, known as the angiotensin I converting enzyme (ACE). But the test is currently carried out to check its activity in regulating blood pressure, rather than its concentration. Up 80% of dieters suffer from the yo-yo effect, returning to their original weight within a year.
The study looked at around 100 women aged 20 to 45, half of whom had maintained their post-diet weight and half of whom had put weight back on. The findings of the research have been published by Dr Ping Wang, a scientist in Professor Mariman’s research group, in the online scientific journal PloS ONE.
A study led by Brian Moss of Wayne State University’s School of Social Work reveals that one third of infants in the U.S. are obese or at risk of obesity. In addition, of the 8,000 infants studied, those found to be obese at 9 months had a higher risk of being obese at 2 years. Other studies have revealed that Infant obesity increases the risk for later childhood obesity and could lead to other obesity-related health problems like heart disease, asthma, high blood pressure and cancer. According to the U.S. Centers for Disease Control and Prevention, childhood and infant obesity has more than tripled in the past 30 years.
Moss, in collaboration with William H. Yeaton from the Institute for Social Research at the University of Michigan in Ann Arbor, published their analysis, “Young Children’s Weight Trajectories and Associated Risk Factors: Results from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B),” in the January/February 2011 issue of the American Journal of Health Promotion. The ECLS-B draws from a representative sample of American children born in 2001 with diverse socioeconomic and racial/ethnic backgrounds. It is one of the first studies to monitor weight status changes of a nationally representative sample of very young children.
For their study, Moss and Yeaton used results from ECLS-B to follow the trajectory of the infants’ weight status at 9 months and 2 years, then performed statistical analyses to examine whether weight persistence, loss or gain was linked to demographic characteristics such as sex, race/ethnicity, geographic region or socioeconomic status. Children above the 95th percentile on standard growth charts were considered to have infant obesity, children in the 85th to 95th percentile were considered at risk for obesity.
Some of their results show that:
• 31.9 percent of 9-month-olds were at risk or obese;
• 34.3 percent of 2-year-olds were obese or at risk for obesity;
• 17 percent of the infants were obese at 9 months, rising to 20 percent at 2 years;
• 44 percent of the infants who were obese at 9 months remained obese at 2 years;
• Hispanic and low-income children were at greater risk for weight status gain;
• Females and Asian/Pacific Islanders were at lower risk for undesirable weight changes;
• 40 percent of 2-year-olds from the lowest income homes were at risk or obese compared to 27 percent of those from the highest income homes.
“This study shows that a significant proportion of very young children in the United States is at risk or is obese,” said Moss. The team notes a consistent pattern of obesity starting early in life. “As obesity becomes an increasing public health concern, these findings will help guide health practitioners by targeting high risk populations and foster culturally sensitive interventions aimed at prevention and treatment of obesity,” Moss said.
“We are not saying that overweight babies are doomed to be obese adults. However, we have found evidence that being overweight at 9 months puts you on track for being overweight or obese later in childhood.”
Researchers at King’s College London and the University of East Anglia have discovered that women who consume a diet high in allium vegetables, such as garlic, onions and leeks, have lower levels of hip osteoarthritis. The findings, published in the BMC Musculoskeletal Disorders journal, not only highlight the possible effects of diet in protecting against osteoarthritis, but also show the potential for using compounds found in garlic to develop treatments for the condition. A relationship between body weight and osteoarthritis was previously recognised, although it is not yet completely understood. This study is the first of its kind to delve deeper into the dietary patterns and influences that could impact on development and prevention of the condition.
Osteoarthritis is the most common form of arthritis in adults, affecting around 8 million people in the UK, and women are more likely to develop it than men. It causes pain and disability by affecting the hip, knees and spine in the middle-aged and elderly population. Currently there is no effective treatment other than pain relief and, ultimately, joint replacement.
The study, funded by Arthritis Research UK, the Wellcome Trust and Dunhill Medical Trust, looked at over 1,000 healthy female twins, many of whom had no symptoms of arthritis. The team carried out a detailed assessment of the diet patterns of the twins and analysed these alongside x-ray images, which captured the extent of early osteoarthritis in the participants’ hips, knees and spine. They found that in those who consumed a healthy diet with a high intake of fruit and vegetables, particularly alliums such as garlic, there was less evidence of early osteoarthritis in the hip joint.
To investigate the potential protective effect of alliums further, researchers studied the compounds found in garlic. They found that that a compound called diallyl disulphide limits the amount of cartilage-damaging enzymes when introduced to a human cartilage cell-line in the laboratory. Dr Frances Williams, lead author from the Department of Twin Research at King’s College London, says: “While we don’t yet know if eating garlic will lead to high levels of this component in the joint, these findings may point the way towards future treatments and prevention of hip osteoarthritis. “It has been known for a long time that there is a link between body weight and osteoarthritis. Many researchers have tried to find dietary components influencing the condition, but this is the first large scale study of diet in twins. If our results are confirmed by follow-up studies, this will point the way towards dietary intervention or targeted drug therapy for people with osteoarthritis.”
Professor Ian Clark of the University of East Anglia said: “Osteoarthritis is a major health issue and this exciting study shows the potential for diet to influence the course of the disease. With further work to confirm and extend these early findings, this may open up the possibility of using diet or dietary supplements in the future treatment osteoarthritis.”
People who weigh more have lower circulating levels of Vitamin D according to recent research conducted at the Rikshospitalet-Radiumhospitalet Medical Center in Oslo, Norway and published in the Journal of Nutrition. Lead researcher, Zoya Lagunova, MD and her colleagues measured the serum levels of Vitamin D and 1,25(OH)2D in 1,779 patients at a Medical and Metabolic Lifestyle Management Clinic in Oslo, Norway. The associations among 1,25(OH)(2)D, serum 25-hydroxyvitamin D [25(OH)D], and body composition were analyzed. Lagunova noted that generally people with higher BMI had lower levels of Vitamin D. Age, season, and gender were also found to influence serum 1,25(OH)(2)D.
Vitamin D is not a true vitamin, but rather a vitamin-steroid thought to play a key role in the prevention of cancer, cardiovascular disease, diabetes, multiple sclerosis and other diseases. It is likely not coincidental that obesity is also a risk factor for many of these diseases. Vitamin D is vital to the regulation of calcium. Studies have shown that calcium deficiency increases the production of synthase, an enzyme that converts calories into fat. It has been shown that calcium deficiency can increase synthase production by up to 500 percent. Vitamin D has also been shown to play a role in the regulation of blood sugar levels; proper blood sugar regulation is vital to the maintenance of a healthy weight. Vitamin D is produced from sunlight and converted into various metabolites. It is stored in fat tissue. According to Lagunova, obese people may take in as much Vitamin D as other people; however, because it is stored in fat it may be less available. This may result in lower circulating levels of Vitamin D.
A previous study conducted by Shalamar Sibley, MD, MPH, an assistant professor of medicine at the University of Minnesota, showed that subjects who have higher levels of Vitamin D at the start of a weight loss diet lose more weight than those with lower levels. The study measured Vitamin D levels of 38 overweight men and women both before and after following an 11-week calorie-restricted diet. Vitamin D levels at the start of diet was an accurate predictor of weight loss…those with higher levels of Vitamin D lost more weight. It was found that for every nanogram increase in Vitamin D precursor, there was an 1/2 pound increase in weight loss.
Seventy-five percent or more of Americans, teenage and older, are Vitamin D deficient according to a recent study published in the Archives of Internal Medicine. According to the Gallup-Healthways Well-Being Index, 26.5% of American are obese. More research needs to be conducted into the exact role Vitamin D plays in obesity and weight loss and the possibility of increased Vitamin D consumption (through the form of supplementation and/or increased sun exposure) being a key factor to achieving a healthy weight.
About a third of some of the most common forms of cancer could be prevented through healthy diet, physical fitness, and limiting alcohol intake, the American Institute for Cancer Research and the World Cancer Research Fund say in a new report. About 7.6 million people die from cancer every year worldwide, and 12.7 million new cases are diagnosed. According to the Union for International Cancer Control, a third of cancer cases could be cured through early diagnosis and treatment and 30% to 40% could be prevented. About 340,000 cases of cancer could be prevented annually in the U.S. if more people started eating a varied and healthy diet, started a regimen of physical activity, limited alcohol intake, and maintained a healthy weight, the new report says.
“Physical activity is recommended for people of all ages as a means to reduce risks for certain types of cancers and other non-communicable diseases,” says Tim Armstrong, MD, of the World Health Organization, says in a news release. “In order to improve their health and prevent several diseases, adults should do at least 150 minutes moderate physical activity throughout the week. This can be achieved by simply walking 30 minutes five times per week or by cycling to work daily.”
To reduce cancer risk, people also should quit smoking, avoid excessive sun exposure, and protect themselves against cancer-causing infections.
Tim Byers, MD, MPH, of the Colorado School of Public Health, says scientists urge Americans “to make the simple lifestyle changes of eating healthy food, getting regular physical activity, and maintaining a healthy weight to reduce cancer risk.” The World Cancer Declaration outlines 11 targets it says could be achieved by 2020 to fight cancer. These goals include: significant drops in global tobacco use, obesity, and alcohol intake; universal vaccination programs for hepatitis B and human papilloma virus (HPV); universal availability of effective pain medication; and efforts to dispel misconceptions about cancer. The health organizations say in a detailed report that the most common cancers in the U.S. and Britain are of the breast, colon/rectum, lung, and prostate.
The American Institute for Cancer Research recommends the following cancer-prevention steps.
- Limit consumption of calorie-dense foods, particularly processed foods high in added sugar, low in fiber, or high in fat.
- Avoid sugary drinks.
- Eat more of a variety of vegetables, fruits, whole grains, and beans.
- Limit consumption of red meats such as beef, pork, and lamb, and avoid processed meats.
- Limit consumption of salty foods and foods processed with sodium.
- Dietary supplements for lowering cancer risk are not recommended.
- Be as lean as possible without becoming underweight.
- Be physically active for 30 minutes or more every day.
New findings from the Monell Center reveal that weight gain of formula-fed infants is influenced by the type of formula the infant is consuming. The findings have implications related to the infant’s risk for the development of obesity, diabetes and other diseases later in life. “Events early in life have long-term consequences on health and one of the most significant influences is early growth rate,” said study lead author Julie Mennella, Ph.D., a developmental psychobiologist at Monell. “We already know that formula-fed babies gain more weight than breast-fed babies. But we didn’t know whether this was true for all types of formula.”
While most infant formulas are cow’s milk-based, other choices include soy-based and protein hydrolysate-based formulas. Protein hydrolysate formulas contain pre-digested proteins and typically are fed to infants who cannot tolerate the intact proteins in other formulas. In adults, pre-digested proteins are believed to act in the intestine to initiate the end of a meal, thus leading to smaller meals and intake of fewer calories. Based on this, the authors hypothesized that infants who were feeding protein hydrolysate formulas would eat less and have an altered growth pattern relative to infants feeding cow’s milk-based formula.
In the study, published online in the journal Pediatrics, infants whose parents had already decided to bottle-feed were randomly assigned at two weeks of age to feed either a cow’s milk-based formula (35 infants) or a protein hydrolysate formula (24 infants) for seven months. Both formulas contained the same amount of calories, but the hydrolysate formula had more protein, including greater amounts of small peptides and free amino acids. Infants were weighed once each month in the laboratory, where they also were videotaped consuming a meal of the assigned formula. The meal continued until the infant signaled that s/he was full.
Over the seven months of the study, the protein hydrolysate infants gained weight at a slower rate than infants fed cow milk formula. Linear growth, or length, did not differ between the two groups, demonstrating that the differences in growth were specifically attributable to weight. “All formulas are not alike,” said Mennella. “These two formulas have the same amount of calories, but differ considerably in terms of how they influence infant growth.”
When the data were compared to national norms for breast-fed infants, the rate of weight gain of protein hydrolysate infants was comparable to the breast milk standards; in contrast, infants fed cow’s milk formula gained weight at a greater rate than the same breast milk standards. Analysis of the laboratory meal revealed the infants fed the protein hydrolysate formula consumed less formula during the meal. “One of the reasons the protein hydrolysate infants had similar growth patterns to breast-fed infants, who are the gold standard, is that they consumed less formula during a feed as compared to infants fed cow’s milk formula” said Mennella. “The next question to ask is: Why do infants on cow’s milk formula overfeed?”
The findings highlight the need to understand the long-term influences of infant formula composition on feeding behavior, growth, and metabolic health. Future studies will utilize measures of energy metabolism and expenditure to examine how the individual formulas influence growth, and how each differs from breastfeeding. Also contributing to the study, which was funded by the National Institute of Child Health and Human Development, were Monell scientists Gary Beauchamp and Alison Ventura.
With eating disorders on the rise among boys, minorities and younger children, doctors need to keep an eye out for unexpected cases, according to the author of a new report. The stereotype that eating disorders affect only affluent, white teenage girls no longer applies, said David S. Rosen, MD, MPH, who wrote a clinical report on the topic that was published in the December issue of Pediatrics. “It’s also happening to boys, young children, people of color and middle-aged women. It’s more of an equal opportunity disorder,” said Dr. Rosen, a professor of pediatrics, internal medicine and psychiatry at the University of Michigan.
Males, for example, now represent up to 10% of all cases of eating disorders. The number of children younger than 12 who are hospitalized for eating disorders increased 119% from 1999 to 2006, according to an analysis by the Agency for Healthcare Research and Quality cited in the report (www.ncbi.nlm.nih.gov/pubmed/21115584/). Young children who develop eating disorders are more susceptible to serious medical consequences such as stunted growth and organ damage, Dr. Rosen said.
Early intervention recommended
He urges physicians, nurses, parents, school social workers and others to intervene early. Health care professionals should take note when patients, particularly young ones, make derogatory comments about their appearance or talk about going on a diet. The report said screening questions about eating patterns and body image should be asked of all preteens and adolescents.
Fewer than 1% of adolescent girls in the U.S. have anorexia, and 1% to 2% percent have bulimia. Experts estimate that between 1% and 14% of Americans exhibit some physical and psychological symptoms of an eating disorder. Male and female athletes, including gymnasts, runners and wrestlers, and performers, such as dancers and models, may be more at risk.
The report said eating disorders may have more of a genetic link, similar to alcoholism and depression, than previously thought. The discovery that some children may be genetically predisposed to the condition may “help to take away some of the blame or stigma,” Dr. Rosen said. With more children obese, physicians should choose their words carefully when counseling a child about his or her weight, Dr. Rosen said. He sees young patients with eating disorders who claim their problems with food began when their doctor told them to lose weight.
Dr. Rosen recommends that physicians discuss healthy eating practices, not dieting, with patients and focus on a healthy lifestyle, not losing weight. “There’s a perception that, like alcoholism, [an eating disorder] never goes away and that the best you can do is keep it under control,” he said. But if caught early, “most children and teens can expect to recover completely.”
The link between obesity and cardiac disease is not merely anecdotal, there is proof for that. Now, there is further proof that even overweight causes a clustering of risk factors for cardio vascular abnormalities. A recent publication in Heart Asia, a British Medical Journal, has showed that there is not much difference between the cardio vascular risk factors in obese and overweight people. “The clutch of risk factors – glucose intolerance, hyper tension, high cholesterol – are all significantly higher among overweight and obese subjects than among normal subjects,” Vijay Viswanathan, MV Hospital for Diabetes and Prof. M.Viswanthan Diabetes Research Center said. He co-authored the article with Shabana Tharkar, also from the Indian hospital.
The study, conducted among two groups – 2021 subjects aged over 20 years, and 1289 subjects aged 8-19 years – indicated that even among overweight, 'non-obese' people, the presence of major cardiovascular risk factors was not significantly different. While the total diabetes prevalence among the obese population is 28.4 per cent, among the overweight population is 25 per cent. Again, with hypertension, the value for the obese group is 34.2 per cent, while for the overweight population it is 27.6 per cent. In contrast, the corresponding values are 16.2 per cent (diabetes) and 20.2 (hypertension).
Similarly, the study showed higher values for triglycerides and high HDL cholesterol for both these groups.
Overweight was defined as a Body Mass Index, equal to, or in excess of 25 kg/m2 and obesity, a BMI of 30 kg/m2 or above. Further worrisome is the increasing rate of overweight and obesity among both men and women from 1995 to 2008, across all age groups. Dr. Viswanathan added that this is the result of rapid urbanisation. “Obesity has already hit the Western world and it is time for Indians to wake up to the alarm bells,” according to the article. Results from previous studies show a lower risk of developing diabetes with just a five per cent initial reduction in weight, Dr. Viswanathan said.
The findings highlight the urgent need for framing direct and indirect strategies to control the rising levels of obesity in the population, in order to substantially reduce the country's non communicable diseases burden, he added. Regulating the diet, reducing intake of fast foods and high-calorie meals, and upping physical activity and exercise on a regular basis would go a long way in keeping weight under control, diabetologists advise.
Individuals who drink three glasses of milk a day decrease their risk of cardiovascular disease by 18 percent, according to new research published in the American Journal of Clinical Nutrition.Researchers at Wageningen University and Harvard University examined 17 studies from the United States, Europe and Japan and found no link between the consumption of regular or low fat dairy and any increased risk of heart disease, stroke or total mortality. “Milk and dairy are the most nutritious and healthy foods available and loaded with naturally occurring nutrients, such as calcium, potassium and protein, to name a few,” said Cindy Schweitzer, technical director of the Global Dairy Platform. “It's about going back to the basics; maintaining a healthy lifestyle doesn't have to be a scientific equation.”
Schweitzer said during the past three decades as research sought to understand influencers of cardiovascular disease, simplified dietary advice including consuming only low fat dairy products emerged. However, in 2010 alone, a significant amount of new research was published from all over the world, supporting the health benefits of dairy. From dispelling the myth that dairy causes heart disease, to revealing dairy's weight loss-benefits, the following is a roundup of select dairy research conducted in 2010:
- U.S. researchers examined 21 studies that included data from nearly 350,000 and concluded that dietary intakes of saturated fats are not associated with increases in the risk of either coronary heart disease or cardiovascular disease. The study was published in the American Journal of Clinical Nutrition.
- A study published in the American Journal of Epidemiology examined 23,366 Swedish men and revealed that intakes of calcium above the recommended daily levels may reduce the risk of mortality from heart disease and cancer by 25 percent.
- An Australian study published in the European Journal of Clinical Nutrition concluded that overall intake of dairy products was not associated with mortality. The 16-year prospective study of 1,529 Australian adults found that people who ate the most full-fat dairy had a 69-percent lower risk of cardiovascular death than those who ate the least.
- A Danish study published in Physiology & Behavior concluded that an inadequate calcium intake during an energy restricted weight-loss program may trigger hunger and impair compliance to the diet.
- An Israeli study published in the American Journal of Clinical Nutrition showed that a higher dairy calcium intake is related to greater diet-induced weight loss. The study sampled more than 300 overweight men and women during two years and found those with the highest dairy calcium intake lost 38-percent more weight than those with the lowest dairy calcium intake.
The amount of dairy recommended per day varies by country and is generally based on nutrition needs and food availability. “In the US and some European countries, three servings of dairy foods are recommended daily, said Dr. Schweitzer.”
The more obese a person is, the poorer his or her vitamin D status, a new study by a team of Norwegian researchers suggests. The study found an inverse relationship between excess pounds and an insufficient amount of vitamin D, which is critical to cell health, calcium absorption and proper immune function. Vitamin D deficiency can raise the risk for bone deterioration and certain types of cancer. The researchers also suggest that overweight and obese people may have problems processing the vitamin properly.
The team noted that after the so-called “sunshine vitamin” is initially absorbed (through either sun exposure or the consumption of such foods as oily fish and fortified milk), the body must then convert it into a usable form, called 1,25-dihydroxyvitamin D. This conversion process, however, seems to be short-circuited among obese people, complicating efforts to gauge their true vitamin D health.
The findings are published in the January issue of the Journal of Nutrition.
To investigate the impact of obesity on vitamin D absorption, the team spent six years tracking 1,464 women and 315 men, with an average age of 49. Based on the participants' body mass index (BMI), an indicator of body fatness calculated from a persons weight and height, the average participant was deemed to be obese. About 11 percent were categorized as “morbidly obese.”
From the outset, overall vitamin D levels were found to be below the healthy range, the authors noted. By the end of the study, overall levels of vitamin D were found to have dropped off “significantly” while BMI readings rose by 5 percent. The research team concluded that having a higher-than-normal weight, body fat and BMI was linked to a poorer vitamin D profile. For example, people with the lowest BMI readings had 14 percent higher vitamin D levels than those with the highest BMI readings. Because vitamin D levels did not correlate properly with 1,25-dihydroxyvitamin D levels (and in fact appeared to have an abnormal inverse relationship), the authors suggested that future efforts to explore vitamin D status among obese people should test for both measures of vitamin D health.
They also suggested that people who are overweight and obese might benefit from vitamin D supplementation and more exposure to sunlight.
SOURCE: Journal of Nutrition, news release, Dec. 14, 2010