December 17th, 2012 by admin in Quackery Exposed
2 Comments »
Miracles are pretty rare events. Except on television’s “Dr. Oz Show,” where they appear with astonishing frequency. Oz of course doesn’t claim to raise the dead or part the Red Sea, but he does raise people’s hopes of parting with their flab. And he’s certainly not shy about flinging the word “miracle” about. But it seems miracles fade as quickly as they appear. Raspberry ketones, acai berries and African mango, once hyped as amazing “fat busters,” have already given way to newer wonders.
Granted, Dr. Oz, or more likely his producers, do not pull miracles out of an empty hat. They generally manage to toss in a smattering of stunted facts that they then nurture into some pretty tall tales. Like the ones about chlorogenic acid or Garcinia cambogia causing effortless weight loss. The former piqued the public’s interest when the great Oz introduced green coffee bean extract as the next diet sensation. Actually “chlorogenic acid” is not a single compound, but rather a family of closely related compounds found in green plants, which perhaps surprisingly, contain no chlorine atoms. The name derives from the Greek “chloro” for pale green and “genic” means “give rise to.” (The element chlorine is a pale green gas, hence its name.)
An “unprecedented” breakthrough, Dr, Oz curiously announced, apparently having forgotten all about his previous weight-control miracles. This time the “staggering” results originate from a study of green coffee bean extract by Dr. Joe Vinson, a respected chemist at the University of Scranton who has a long-standing interest in antioxidants, such as chlorogenic acid. Aware of the fact that chlorogenic acid had been shown to influence glucose and fat metabolism in mice, Vinson speculated that it might have some effect on humans as well. Since chlorogenic acid content is reduced by roasting, a green bean extracts was chosen for the study.
In cooperation with colleagues in India who had access to volunteers, Dr. Vinson designed a trial whereby overweight subjects were given, in random order, for periods of six weeks each, either a daily dose of 1,050 mg of green coffee bean extract, a lower dosage of 700 mg, or a placebo. Between each six-week phase there was a two-week “washout” period during which the participants took no supplements. There was no dietary intervention; the average daily calorie intake was about 2,400. Participants burned roughly 400 calories a day with exercise. On average there was a loss of about a third of a kilogram per week. Interesting, but hardly “staggering.” And there are caveats galore.
The study involved only eight men and eight women, which amounts to a statistically weak sample. Diet was self-reported, a notoriously unreliable method. The subjects were not really blinded since the high dose regimen involved three pills, the lower dose only two. A perusal of the results also shows some curious features. For example, in the group that took placebo for the first six weeks, there was an 8 kilogram weight loss during the placebo and washout phase, but almost no further loss during the high dose and low dose phases. By the time, though, that critics reacted to Oz’s glowing account, overweight people were already panting their way to the health food store to pick up some green coffee bean extract that might or might not contain the amount of chlorogenic acid declared on the label. As for Dr. Oz, he had already moved on to his next “revolutionary” product, Garcinia cambogia, unabashedly describing it as the “Holy Grail” of weight loss.
We were actually treated to the Grail in action. Sort of. Dr. Oz, with guest Dr. Julie Chen, performed a demonstration using a plastic contraption with a balloon inside that was supposed to represent the liver. A white liquid, supposedly a sugar solution, was poured in, causing the balloon, representing a fat cell, to swell. Then a valve was closed, and as more liquid was introduced, it went into a different chamber, marked “energy.” The message was that the valve represents Garcinia extract, which prevents the buildup of fat in fat cells. While playing with balloons and a plastic liver may make for entertaining television, it makes for pretty skimpy science.
Contrary to Dr. Oz’s introduction that “you are hearing it here first,” there is nothing new about Garcinia. There’s no breakthrough, no fresh research, no “revolutionary” discovery. In the weight control field, Garcinia cambogia is old hat. Extracts of the rind of this small pumpkin-shaped Asian fruit have long been used in “natural weight loss supplements” Why? Because in theory, they could have an effect.
The rind of the fruit, sometimes called a tamarind, is rich in hydroxycitric acid (HCA), a substance with biological activity that can be related to weight loss. Laboratory experiments indicate that HCA can interfere with an enzyme that plays a role in converting excess sugar into fat, as well as with enzymes that break down complex carbohydrates to simple sugars that are readily absorbed. Furthermore, there are suggestions that Garcinia extract stimulates serotonin release which can lead to appetite suppression.
Laboratory results that point toward possible weight loss don’t mean much until they are confirmed by proper human trials. And there have been some. Fifteen years ago a randomized trial involving 135 subjects who took either a placebo or a Garcinia extract equivalent to 1500 mg of HCA a day for three months, showed no difference in weight loss between the groups. A more recent trial involving 86 overweight people taking either two grams of extract or placebo for ten weeks echoed those results. In-between these two major studies there were several others, some of which did show a weight loss of about one kilogram over a couple of months, but these either had few subjects or lacked a control group. Basically, it is clear that if there is any weight loss attributed to Garcinia cambogia, it is virtually insignificant. But there may be something else attributed to the supplement, namely kidney problems. Although incidence is rare, even one is an excess when the chance of a benefit is so small. So Garcinia cambogia, like green coffee bean extract, can hardly be called a miracle. But it seems Dr. Oz puts his facts on a diet when it comes to fattening up his television ratings.
joe.schwarcz@mcgill.ca
Joe Schwarcz is director of McGill University’s Office for Science & Society (mcgill.ca/oss). He hosts The Dr. Joe Show on CJAD Radio 800 AM every Sunday from 3 to 4 p.m.
September 7th, 2012 by Dr. Val Jones in Health Tips, Opinion
No Comments »
I recently found my way to an interesting NPR podcast via a link from Dr. Ranit Mishori (@ranitmd) on Twitter. The host of the show interviewed a physician (Dr. Mishori), an obesity researcher (Sara Bleich), and a family nurse practitioner (Eileen O’Grady) about how healthcare providers are trying (or not trying) to help patients manage their weight. Several patients and practitioners called in to participate.
First of all, I found it intriguing that research has shown that the BMI of the treating physician has a significant impact on whether he or she is willing to counsel a patient about weight loss. Normal weight physicians (those with a BMI under 25) were more likely to bring up the subject (and follow through with weight loss and exercise planning with their patients) than were physicians who were overweight or obese. Sara Bleich believes that this is because overweight and obese physicians either don’t recognize the problem in others who have similar body types, or that their personal shame about their weight makes them feel that they don’t have the right to give advice since they don’t practice what they preach. While 60% of Americans are either overweight or obese, 50% of physicians are also in those categories.
Although it’s not entirely surprising that overweight/obese physicians feel as they do, it made me wonder what other personal conditions could be influencing evidence-based patient care. Is a physician with high blood pressure less apt to encourage salt restriction or medication adherence? What about depression, smoking cessation, or erectile dysfunction? Are there certain personal diseases or conditions that impair proper care and treatment in others?
Several callers recounted negative experiences with physicians where they were “read the Riot Act” about their weight. One overweight woman said she handled this by simply avoiding going to the doctor at all, and another obese man said his doctor made him cry. However, the man went on to lose 175 pounds through diet and exercise modifications and said that the “tough love” was just what he needed to galvanize him into action.
Dr. Mishori felt that the “Riot Act” approach was rarely helpful and usually alienated patients. She advocated a more nuanced and sensitive approach that takes into account a patient’s social and financial situation. She explained that there’s no use advocating personal training sessions to a person on food stamps. Physicians need to be more sensitive to patients’ living conditions and physical abilities.
In the end, I felt that nurse practitioner Eileen O’Grady contributed some helpful observations – she argued that the rate-limiting factor in reversing obesity is not information, but motivation. Most patients know what they “should do” but just don’t have the motivation to start, and keep at it till they achieve a healthy weight. Ms. O’Grady devoted her practice to weight loss coaching by phone, and she believes that telephones have one big advantage over in-person visits: patients are more likely to be honest when there is no direct eye contact with their provider. Her secret to success, beyond a non-judgmental therapeutic environment, is setting small, attainable goals. She says that if she doesn’t believe the patient has at least a 70% chance of success, they should not set that particular goal.
Starting goals may be as simple as “finding a workout outfit that fits.” As the patient grows in confidence with their successes, larger, broader goals may be set. Weight loss coaching and intensive group therapy may be the most motivating strategy that we have to help Americans shed unwanted pounds. Apparently, the USPS Task Force agrees, as they recommend “intensive, multicomponent behavioral interventions” for those who screen positive for obesity in their doctors’ offices.
I think it’s unfortunate that most doctors feel that they “simply don’t have time to counsel patients about obesity.” Diet and exercise are the two most powerful medical tools we have to combat many chronic diseases. What else is so important that it’s taking away our time focusing on the “elephant in the room?” Pills are not the way forward in obesity treatment – and we should have the courage to admit it and do better with confronting this problem head-on in our offices, and also in our own lives.
July 26th, 2012 by Dr. Val Jones in Health Tips, Opinion, True Stories
6 Comments »
I was taken aback by a recent conversation I had with a gym owner. She is interested in encouraging middle-aged women to come to the gym for beginner-level fitness classes and was planning a strategy meeting for her staff and key clients. I asked if I could join and she said that I was expressly un-invited. Slightly miffed I asked why that was so – after all, I’m a rehab physician who has devoted my career to getting people moving.
“You’re too advanced.” She said. “Beginners wouldn’t relate to the way you work out, we’re really more focused on creating a less intimidating environment for women.”
“You mean, like the Planet Fitness ads? The ones where athletes are not welcome?” I asked, confusedly.
“I don’t like those ads but the idea is the same. Beginners feel deflated by working out with people who are in far better shape. They don’t even want their instructor to look too fit.”
“You’re kidding me. Women would actually prefer working out with a chubby trainer?”
“Yes. In fact, I’ve had some women come to the gym and actually request NOT to be paired up with some of our personal trainers specifically because they look too fit. They are afraid they will be asked to work too hard, beyond their comfort zone.”
“So why are they coming to the gym in the first place?” I asked. “What is motivating them if they don’t want to work out hard or change their bodies in the direction of athletic-looking trainers?”
“They’re just interested in staying the way they’ve always been. Maybe they’ve started putting on weight after they hit their 40’s and 50’s and just want to get back to where they were in their 30’s. They’re not interested in running marathons or lifting the heaviest weights in the gym. They don’t want to be pushed too hard, and they prefer trainers who look healthy but not extreme.”
Medically speaking, it doesn’t take extreme effort to be healthy. Many studies have shown that regular walking is adequate to stave off certain diseases, and weight loss success stories (chronicled at the National Weight Control Registry for example) usually result from adherence to a calorie-restricted diet and engagement in moderate exercise.
In a sense, these women who “don’t want to work that hard” are right – they don’t have to perform extreme feats to be healthy. However, I am still fascinated by the preference for “average looking” trainers and the apparent bias against athleticism. This must be a fairly common bias, though, because national gym chains (like Planet Fitness) have picked up on it and made it the cornerstone of their marketing strategy. “No judgments” – except if you’ve got buns of steel, I guess.
When I choose a trainer I am looking for someone who embodies the best of what exercise can offer. An athlete who has practiced their craft through years of sweat and effort… because that’s my North Star. Sure, I may never arrive at the North Star myself, but I like to reach. And that’s what motivates me.
But for others, having a professional athlete for a trainer may be a mindset misfit. If your aspiration is to be healthy but not athletic, then it makes sense to find inspiration in those who embody that attitude and lifestyle. The important thing is that we all meet the minimum exercise requirements for optimum health. According to the CDC, that means:
* 2 hours and 30 minutes (150 minutes) of moderate-intensity aerobic activity (i.e., brisk walking) every week
and
* muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms).
How you get there, and with whom you arrive, is up to you. Chubby or steely – when it comes to health and fitness the best mantra is, “whatever works!”
January 5th, 2012 by RyanDuBosar in Research
No Comments »
Consuming excess calories increases body fat, regardless of how many calories come from protein. High-protein diets do affect energy expenditure and storage of lean body mass, just not body fat storage.
To evaluate the effects of overconsumption of low-, normal-, and high-protein diets on weight gain, researchers conducted a single-blind, randomized controlled trial of 25 healthy, weight-stable adults in an inpatient metabolic unit in Baton Rouge, La. Patients were ages 18 to 35 with a body mass index between 19 and 30. The study was headed by George A. Bray, MD, MACP.
After consuming a weight-stabilizing diet for 13 to 25 days, participants were randomized to diets containing 5% of energy from protein (low protein), 15% (normal protein) or 25% (high protein). Only the kitchen staff who supervised participants while they were eating knew the assignments. There was no prescribed exercise, and alcohol and caffeine were restricted.
Patients were Read more »
*This blog post was originally published at ACP Internist*
December 28th, 2011 by HarvardHealth in Health Tips, Research
1 Comment »
When you sit quietly, your heart slips into the slower, steady pace known as your resting heart rate. A new study suggests that an increase in this rate over time may be a signal of heart trouble ahead.
Your heart rate changes from minute to minute. It depends on whether you are standing up or lying down, moving around or sitting still, stressed or relaxed. Your resting heart rate, though, tends to be stable from day to day. The usual range for resting heart rate is anywhere between 60 and 90 beats per minute. Above 90 is considered high.
Many factors influence resting heart rate. Genes play a role. Aging tends to speed it up. Regular exercise tends to slow it down. (In his prime, champion cyclist Lance Armstrong had a resting heart rate of just 32 beats per minute.) Stress, medications, and medical conditions also influence the heart rate.
In today’s Journal of the American Medical Association, researchers from Norway report Read more »
*This blog post was originally published at Harvard Health Blog*
