Archive for January, 2014

Politicians Beware of Dietary Supplement Businessmen

January 23rd, 2014

Source: Politico.com

Virginia Governor Robert F. McDonnell and his wife for accepting gifts from a dietary supplement businessman. McDonnell had state health officials meet with Star Scientific Inc. representatives who wanted its supplement, Anatabloc, included in the basic health plan for state employees. The Governor and his wife openly endorsed Anatabloc.

Jonnie R. Williams, head of Star Scientific Inc., gave over $100,000 in corporate jet travel to the governor and personal gifts to the McDonnell’s over $145,000. Williams had run afoul of the Securities and Exchange Commission, which forced him to pay back nearly $300,000 for using research with false claims to promote a medical business. Star Scientific has three shareholder lawsuits against it alleging the company made false or misleading statements to boost Anatabloc.

Like all other dietary supplements, approval by the Food and Drug Administration before sale is not required. The company claims that Anatabloc helps “reduce inflammation and support a health metabolism.” However, as reported by the Richmond (VA) Times Dispatch, the company has put out at least 15 press releases on scientific studies it commissioned implying Anatabloc might mitigate the underlying causes of Alzheimer’s disease, multiple sclerosis, thyroiditis and traumatic brain injuries. It’s advertising also promotes Anatabloc for joint pain and inflammation, even though the active ingredient has only been tested in pre-clinical, animal studies. In December 2013, the FDA informed Star Scientific that it was improperly selling Anatabloc and the company needed FDA approval to sell it as a drug.

Somewhat ironically (or not) Governor McDonnell received a combined M.A./J.D. degree from Christian Broadcasting Network University (now called Regent University). Christian Broadcasting Network University was founded by Pat Robertson, conservative religious broadcaster and one time Presidential candidate. Robertson sold another dietary supplement, described as an “age defying shake” and was accused of using his tax-deductible contributions to the school  to promote a commercial product.  In one of his promotions, Robertson, then 76 years old, claimed that he could leg-press 1,000 pounds, more than the world record.

McDonnell should have seen in coming. In 2002, Tony Blair was Prime Minister of the United Kingdom. His wife, Cherie Blair, became involved with another dietary supplement businessman, Peter Foster. Foster was an Australian who had been convicted and jailed on three continents for offences involving weight loss products and property transactions. Foster became a financial advisor to Blair and assisted her with the purchase of two apartments. Cherie Blair denied the involvement but evidence came out to the contrary.

As long as the dietary supplement industry can operate without showing scientific basis for its products, it will remain an easy arena for scam artists who can pocket millions, often from weight loss products. The FDA and Federal Trade Commission can do a lot more enforcement of current laws but eventually Congress will have to bring the dietary supplement industry under tougher supervision.

 

Where is Your New Year’s Resolution? Or, Where did I put my Adaptive Thermogenesis?

January 17th, 2014

It’s mid-January: do you know where your New Year resolution went? You know the one about losing weight.

So maybe you are losing the weight you put on over the holidays? Maybe you are underway with a good weight loss program? Maybe you have already given up? No matter what your status, there is something you should know:

The human body is programmed to defend its weight and, when it senses weight loss, it starts cutting down its energy expenditure…big time!

Let’s talk about energy expenditure or “EE”. About 65-70% of calories burned each day are used to keep the routine body functions going, e.g. pumping blood, working the lungs, kidneys and liver. About 10% are used up in thermogenesis or the digestion of food. The rest, about 20%, is spent by the muscles in physical activity.

As far back as 1987, researchers compared the daily resting metabolic rate (RMR) of obese women who had lost weight and were no longer obese with women who were  never obese. The researchers found that the post-obese women had metabolic rates approximately 15% lower than the never-obese group and they ate less.

So, metabolism in persons who have lost weight and those who are lean may not be the same.

Exercise and the heat value of food are skewed against those with obesity. In one experiment, 10 lean women and 10 women with moderate obesity were measured during periods of eating and exercise. Eating before exercise increased the exercise metabolic rate in lean women by 11% but only by 4% in women with obesity. The thermic effect of food was 2.54 times greater during exercise than at rest for the lean group, but only 1.01 greater for the women with obesity.

In a now classic 1995 paper by Jules Hirsch, Rudy Leibel and Michael Rosenbaum at Columbia University found that when a body loses weight, it adjusts by reducing its energy expenditure. This effect is so strong that an obese person who went from 250 lbs to 200 lbs would have to consume about 30% less than a 200 lbs person who had not lost weight just to maintain the same weight. This extra-reduction in food intake would have to continue indefinitely if the person were to maintain their weight loss.

This process, called by researchers “Adaptive Thermogenesis” can persist after active dieting for up to a year in one study.  In an experiment involving subjects with severe obesity who were on a program of diet restriction and vigorous physical activity, researchers saw dramatic weight loss (over 30%) but a slowing of the resting metabolic rate (RMR) “out of proportion to the decrease in body mass, demonstrating a substantial metabolic adaption.”

Some researchers considered adaptive thermogenesis a major factor in the plateauing one sees in dieters, the increase in hunger and the eventual regain of lost weight. In one study of short-term severe diet and exercise subjects, the ‘metabolic compensation’ was seen as a major contributor to the less-than-expected weight loss. Individuals will have different adaptions to weight loss. In some cases, the effect can be significant. Tremblay et al state, “Indeed, as it is difficult to prescribe food intake that imposes an energy deficit exceeding 700-800 kcal per day to obese individuals, the decrease in energy expenditure in response to weight loss can entirely compensate for this prescribed deficit.”

Others are less sure. They seem to accept adaptive thermogenesis but see measurement problems and questions as to its utility in weight management.

The point is that our bodies contain a defensive mechanism against the disease of obesity. Until we realize that our strategies for prevention and treatment are like a novice chess player going up against a Grand Master. The point is: obesity is a lot tougher than our simplistic policy prescriptions assume.

The quandary of obesity has been expressed by Tremblay Chaput and Doucet in their article “Obesity: a disease or a biological adaption? An Update,“ Additionally, substantial body fat loss can complicate appetite control, decrease energy expenditure to a greater extent than predicted, increase the proneness to hypoglycaemia (low blood sugar) and its related risk towards depressive symptoms, increase the plasma and tissue levels of persistent organic pollutants that promote hormone disruption and metabolic complications, all of which are adaptations that can increase the risk of weight regain. In contrast, body fat gain generally provides the opposite adaptations, emphasizing that obesity may realistically be perceived as an a priori biological adaptation for most individuals. Accordingly, prevention and treatment strategies for obesity should ideally target the main drivers or root causes of body fat gain in order to be able to improve the health of the population.”

 

Is Fast Food the Villain?

January 16th, 2014

So, the food police often point to fast food consumption as the main contributor to obesity, especially childhood obesity. So Barry Popkin and colleagues decided to look at the relative contribution of fast food compared to the rest of the diet. They looked at 4, 446 children, aged 2-18, from NHANES 2007-2010 and identified two dietary patterns: Western and Prudent. They found that half of US children consumed fast foods. 30% had most of their energy intake from fast food; 10.5% consumed more than 30% from fast food. Consuming a “Western diet” was more likely among fast-food low consumers. The remainder of the diet was independently associated with obesity, whereas fast food consumption was not.

More evidence on obesity and mortality. Where did the obesity paradox go?

January 15th, 2014

The January 16, 2013 issue of the New England Journal of Medicine contains an article by Frank Hu and colleagues looking at mortality among adults with incident type 2 diabetes by Body Mass Index (BMI). Using two large databases, they found a J-shaped association between BMI and mortality among those who had ever smoked and a direct, linear relationship among those who had never smoked. They found no evidence of an “obesity paradox,” the supposed protective effective of overweight. They concluded, “…given the relationship of overweight and obesity to other critical public health end points (e.g. cardiovascular disease and cancer), the maintenance of a healthy body weight should remain the cornerstone of diabetes management, irrespective of smoking cessation.” The article is a contribution to the understanding of obesity’s relationship with premature mortality but will surely not be the last word on this topic.

 

Hunger, Prader-Willi Sydrome and differences between the brains of persons at normal weight and with obesity

January 15th, 2014

A New York Times report today by Andrew Pollock details the efforts of researchers and drug companies to unravel the mysteries of Prader-Willi Syndrome. Prader-Willi Syndrome is marked by insatiable appetite and obesity. Patients often slow metabolisms, intellectual difficulties and autistic behavior. (For more information see the Prader-Willi Syndrome Association website.) The condition is known to be caused by missing segments on chromosome 15. While Prader-Willi is a genetic disease, it is not necessarily found in families. 70% of cases are due to a deletion in chromosome 15 from the father; deletion from the maternal side is responsible for about 20%.  This is known as genomic imprinting where the gene turns on or off depending on which parent contributes it.

Drug developers Ferring Pharmaceuticals, Rhythm, Arena Pharmaceuticals (which sells Belviq, an FDA approved drug for weight loss) and Zafgen are looking at drugs for the condition. Zafgen is releasing results of a small clinical trial today.

While Prader-Willi is a rare condition and is well-understood regarding its genetic cause, research on the syndrome is helping to open up research on the fundamental aspects of hunger.

One of the great gaps in public and policy-makers understanding of obesity is the role of hunger, driven by powerful networks within our bodies. Hunger is clearly one of the most powerful of human emotional states as it involves existential survival, much like the inability to breathe or drowning. In my experience, many persons with obesity report nearly constant states of hunger which our food-laden environment is almost universally able to slake. But reports from individuals are a poor substitute for research. Now, in the past decade, science has filled in the gaps.

After a meal, appetite is suppressed; after energy expenditure hunger is increased. Those sensations, satiety and hunger, are caused by changes in nutrients and hormones, including PYY, GLP-1, ghrelin, leptin and insulin circulating in the body. In normal physiology, the hypothalamus balances the food intake with the metabolic requirements. This system works, usually, with great precision. This appetite process is called homeostatic. Non-homeostatic food control is driven by sight, smell, taste, habits, emotional and economic influences. The brains areas involved in nonhomeostatic food control include the hippocampus, the amygdala, insula, striatum and orbitofrontal cortex. The two systems are not independent but highly integrated.

Recent research points to understanding that higher food intake in persons with obesity is due, probably in substantial part, to differences in how the brains of  persons with obesity respond to food cues compared to  persons at “normal” weights.

Researchers using techniques such as functional Magnetic Resonance Imaging (fMRI) are mapping the physiological networks of hunger and are understanding  why we get hungry and why maintaining weight loss is so hard. FMRI allows scientists to locate specific areas of the brain which show responses to specific stimuli. Thus they can compare obese and lean subjects in different conditions. (For an explanation of the use of fMRI studies in appetite regulation see this article from de Silva and colleagues and from which this illustration is taken.

Using fMRI, researchers at Emory University have identified areas in the brain identified with taste and the reward system that ‘light up’ when subjects just looked at pictures of appetizing food.  Meanwhile, other researchers, also using fMRI, found different reactions to pictures of high-calorie foods between men and women. When healthy subjects were given injections of ghrelin, fMRI scans showed increased brain activity in response to pictures of food and were correlated with self-reported hunger ratings. (Ghrelin is a peptide hormone that stimulates hunger and food consumption.) Just in October, a study was published showing that images of high fat foods produced stimulation of the brain’s reward network in Hispanic females.

It isn’t only pictures of food which tweak the brain. Subjects with obesity differed from lean subjects in which area of the brain responded to food aromas. The brain areas affected by food aromas are similar to those affected by addictive substances, like alcohol.

In short, individuals prone to weight gain and obesity have altered neuronal responses to food cues in brain regions known to be important in energy intake regulation and these differ from lean person’s responses.

Of great concern is when such differences occur? A study from the University of Kansas Medical Center used fMRI on children and adolescents, ages 10-16, half at a healthy weight and half with obesity. They found the obese group showed greater activation to food pictures both before and after a meal than the healthy weight group. Unlike the healthy weight group, the obese group’s response to food stimuli did not diminish significantly after eating. The authors concluded, “This study provides initial evidence that obesity, even among children, is associated with abnormalities in the neural networks involved in food motivation, and the origins of neural circuitry dysfunction associated with obesity may begin in early life.”

This understanding of obesity has great implications for the prevention and treatment of obesity and for the establishment of effective public policies.

Read this to understand where we are on obesity

January 15th, 2014

If you read nothing else about obesity this year, read this elegant summary of where we stand from John Cawley, Ph.D. of Cornell University.

 

Few Primary Care Physicians Treat Obesity

January 14th, 2014

Only a quarter of  U.S. primary care physicians surveyed are doing a thorough job of helping patients achieve and maintain a healthy weight, finds a study in the American Journal of Health Promotion.

“We found that most primary care practices have few resources for supporting efforts to assess and counsel patients about diet, exercise and weight control,” said lead author Carrie Klabunde, Ph.D., of the cancer control and population sciences division of the National Cancer Institute.

A random sample of 1,740 U.S. physicians participated in the study. Each participant completed two sequential questionnaires, one about their work with patients and one about their practice’s resources. 26 percent of the participating physicians reported closely following established guidelines for what the authors call “energy balance care.” Such guideline-based care would include regular assessment of BMI, counseling on nutrition, physical activity or weight control, and systematic tracking of patients’ progress with weight issues over time.

The survey group included office-based family physicians or general internists, obstetrician/gynecologists and pediatricians.  Striking specialty differences emerged, with comprehensive weight management services being most commonly offered by pediatricians (40.1 percent) and least often by obstetricians/gynecologist (8.4 percent).

Practices located in the Southeast and in smaller cities or rural areas were less likely to provide comprehensive services than ones in the Northeast or in larger cities.  Female physicians and non-white physicians more often provided comprehensive services than males and whites did.

Klabunde noted that the availability of nonphysician staff such as dieticians, nutritionists or health educators and the use of full electronic health records (EHRs) and reminders—which support comprehensive services—were especially rare. In addition, the study showed that practices that billed for energy balance services were more likely to provide such counseling and to routinely track patients’ progress, as compared to those that didn’t bill for the services.

When a primary care physician does seriously encourage patients to control their weight, Klabunde said, their support can “serve as an important prompt for overweight or inactive individuals to adopt better habits.”  (Source: Health Behavior News Service, Center for Advancing Health)

More than 80% of PCPs reported having information resources on diet, physical activity and weight control available but fewer billed for services, used reminder services or received incentive payments. PCPs using electronic medical records or those that billed provided weight management care more often and comprehensively. Pediatricians were more like and ob-gyns less likely that peers to provide treatment in the study.

 

Only 25% of US Youth Meet Physical Activity Targets

January 14th, 2014

The National Center on Health Statistics has issued a report on physical activity in US youth aged 12-15 in 2012. They found (based on self-reports) that one-quarter of US youth engage in moderate to vigorous physical activity every day (excluding gym classes). 7.6% engaged in no physical activity on any day of the week. Slightly more boys engaged in daily physical activity than girls. 18% of boys with obese engaged in daily physical activity compared to 29.5% of normal-weight and 29.5% of overweight boys. Among girls, there was a similar pattern although the differences were not significant.

The report notes that the relationship between obesity and physical activity is not clear cut. While it is widely assumed that low physical activity precedes obesity, there is evidence that it is high body weight which precedes low physical activity.

The results somewhat track a recent study of leisure-time physical activity in adults which found that only 25% engaged in leisure time physical activity, although the trend was showing a decline in no leisure time physical activity.