You may look thin and be too fat

Research highlighting the danger of fat around vital organs could change the way we tackle obesity. Professor Jimmy Bell, a molecular imaging expert, and a team of researchers have recently discovered that, in fact, an outwardly trim person can carry a higher proportion of dangerous hidden fat than an overweight one, if that fat is around vital organs. The team has used a magnetic resonance imaging (MRI) scanner at Hammersmith Hospital in London to map the fat distribution of 600 volunteers. Their results suggest that up to four in 10 people could be “tofi” – thin outside, fat inside.

Previous research has shown someone with a lot of internal fat around the liver, gut, heart and pancreas, or streaked through under-used muscles, has a higher risk of heart disease, type 2 diabetes, hypertension and some cancers than someone with high levels of external fat. “Traditional ways of measuring body fat, such as BMI, give people the wrong idea about how much fat they have, as it says nothing about internal storage. People become obsessed by dieting, but doing this without exercise means they may be putting down fat in the wrong places. We want to get away from that and focus on maximising the health benefits of physical activity without dramatic lifestyle changes.”

Simon Relph, a marketing art director from Sydenham, London, and Neil Ferguson, 23, a marketing designer from Bexley Village, Kent, provide a good example of why our current methods of evaluating weight-related health risks are so flawed. Simon, 41, has a BMI of 27.7, but admits to not doing much exercise. His MRI scan shows he is carrying 15 litres of internal fat. His colleague Neil, 23, has a BMI of 28.1. Yet he plays football three to four times a week and goes to the gym regularly. He admits to “love handles” around his waist, but has only four litres of internal fat.

The researchers believe our current view of the relationship between diet, physical activity and health is far too simplistic. This is where the so-called intervention studies being carried out by Prof Bell’s team come in. Groups of individuals will be put through 16-week programmes of exercise of different intensities and frequencies. Their progress will be accurately measured with MRI scans, and compared with control groups. The ultimate objective is to be able to provide far more accurate advice on how someone should exercise, based on their gender, ethnicity and genetic make-up.

Take Your Vitamin

Even with the best dietary intentions, we often fall short of meeting all our nutritional needs. One answer is a daily multivitamin, which is safe, effective, and can go a long way toward correcting any nutritional deficiencies. Of course, the ideal way to get your nutrients is still from food. Food not only supplies vitamins and minerals, but also gives us fiber and a host of other healthy compounds, like phytochemicals and antioxidants, that interact with each other in ways that supplements can’t. The scientific community used to believe that a varied, healthful diet would provide all the vitamins and minerals we need. But recent surveys show that most American diets fall short of satisfying the minimum daily requirements for several vitamins and minerals. Researchers have concluded that a single daily multivitamin/mineral pill may be the answer for achieving optimum health and preventing chronic diseases.

Approximately 40% of Americans take supplements, according to the third U.S. National Health Examination Survey. And the most popular supplement is the multivitamin. One important point: a daily multivitamin supplements your diet; it’s not intended to correct a bad diet. The benefit of a daily multi is that it can make up for minor deficiencies in your diet that could eventually help lead to chronic disease. In fact, a study published in the August 2003 Journal of Nutrition found that men and women who took multivitamins significantly reduced their risk for a first heart attack. The body needs roughly 40 vitamins and minerals each day for good health, and it’s not always easy to get all of those from food. Taking a daily multivitamin certainly won’t hurt, even if your diet is already chock full of vitamins and minerals. ~ Kathleen Zelman, MPH, RD, LD

FDA Approves Non-Prescription Diet Pill

Washington Post: Dieters got a new tool Wednesday to help them take off the extra pounds _ the first government-approved nonprescription diet pill. The Food and Drug Administration said the fat-blocking weight-loss pill orlistat, which has been available by prescription, can be sold in a reduced-strength version over the counter. The drug is intended for people 18 and older to use along with a reduced-calorie, low-fat diet and exercise. “Using this drug alone is unlikely to be beneficial,” Ganley said at a telebriefing.

While some dietary supplements make weight-loss claims, Ganley said this is the first nonprescription drug approved by the agency for that purpose. Ganley said in trials, for every five pounds people lost through diet and exercise, those using orlistat lost an additional two to three pounds. When taken with meals, orlistat blocks the absorption of about one-quarter of any fat consumed. That fat _ about 150 to 200 calories worth _ is passed out of the body in stools, which can be loose as a result. About half of patients in trials experienced gastrointestinal side effects.

Helicobacter pylori (H. pylori)

Helicobacter pylori is a bacterium that infects the mucus lining of the stomach and duodenum. During my undergraduate research, our sister lab was working to characterize the flagella of this little guy. We discussed H. Pylori in my Cell Bio course last week, and given its importance, I thought this was an imporant bacteria for all to know about.

Distilled from Wikipedia and Lecture Notes: Found in up to 50% of the world’s population, making it the most common infectious disease worldwide, a main cause of peptic ulcers and stomach cancer. H. pylori is an unusual bacteria — the only known bacteria that can cause cancer and one of the only bacteria that can survive in the acidic environment of the stomach. The corkscrew-shaped bacteria drills itself into the stomach lining and, while nourishing itself, reduces the stomach’s ability to produce acid. This often leads to pepticulcers, non-Hodgkins lymphoma of the stomach and gastricadenocarcinoma. Now usually can be eradicated with a combination of proton pump inhibitors and antibiotics.

In their original paper, Robin Warren and Barry Marshall (Australians who studied the bug) contended that most stomach ulcers and gastritis were caused by colonization with this bacterium, not by stress or spicy food as had been assumed before. The medical community was slow to recognize the role of this bacterium in stomach ulcers and gastritis, believing that no bacterium could survive for long in the acidic environment of the stomach. The community began to come around after further studies were done, including one in which Marshall drank a Petri dish of H. pylori, developed gastritis, and the bacteria were recovered from his stomach lining, thereby satisfying three out of the four Koch’s postulates.

Infection may be symptomatic or asymptomatic (without visible ill effects). It is estimated that up to 70% of infection is asymptomatic. The bacteria have been isolated from feces, saliva and dental plaque of infected patients, which suggests gastro-oral or fecal-oral as possible transmission routes. Infection rates vary from nation to nation – the West (Western Europe, North America, Australasia) having rates around 25% and much higher in the Third World. In the latter, it is common, probably due to poor sanitary conditions, to find infections in children. In the United States, infection is primarily in the older generations and the poorest. This is largely attributed to higher hygiene standards and widespread use of antibiotics. However, antibiotic resistance is appearing in H. pylori . It is widely believed that in the absence of treatment, H. pylori infection–once established in its gastric niche–persists for life.

Unhappy Meals

NY Times: Eat food. Not too much. Mostly plants.

That, more or less, is the short answer to the supposedly incredibly complicated and confusing question of what we humans should eat in order to be maximally healthy. I hate to give away the game right here at the beginning of a long essay, and I confess that I’m tempted to complicate matters in the interest of keeping things going for a few thousand more words. I’ll try to resist but will go ahead and add a couple more details to flesh out the advice. Like: A little meat won’t kill you, though it’s better approached as a side dish than as a main. And you’re much better off eating whole fresh foods than processed food products. That’s what I mean by the recommendation to eat “food.” Once, food was all you could eat, but today there are lots of other edible foodlike substances in the supermarket. These novel products of food science often come in packages festooned with health claims, which brings me to a related rule of thumb: if you’re concerned about your health, you should probably avoid food products that make health claims. Why? Because a health claim on a food product is a good indication that it’s not really food, and food is what you want to eat…

This is a pretty long essay (12 pages) but this is a subject we discuss quite a bit, so read on.

The Science behind Collaborative Tagging Sites like del.icio.us

A team of physicists from the University of Rome “La Sapienza” sought to determine the underlying statistical properties of this new information paradigm by studying the behaviors of tags—single words used to describe the content of a linked article or photo—on the social bookmarking/collaborative tagging sites del.icio.us and Connotea. “The idea was to try and see if we could apply complex systems science methods to modeling a system which is an IT system, but exposing, in a very explicit and complex way, the social component—the activity of people,” first author Ciro Cattuto says. “In this system, the linguistic element—the word, the symbol—is a dynamical entity and plays the role of a particle in statistical mechanics.” After studying the manner in which certain tags were associated with a pair of selected ones, the researchers determined that user behavior in collaborative tagging schemes followed a power law in which certain words were highly associated with the chosen tags. Their model exemplifies two primary aspects of user behavior: preferential attachment and aging of resources.

Preferential attachment can also be described as a copying attitude. Cattuto, who performed the research with Vittorio Loreto and Luciano Pietronero, offers the example of linking to a photo or article about New York City. The person posting the link can tag the item in several ways, a few of which are “nyc,” “newyork_city,” or newyork. The choices of previous del.icio.us users, however, are likely to influence the next group of users. “There is pressure, in essence,” Cattuto explains, “because if you use tags that are already widespread within the system, people are able to find your entries—so, using popular tags makes your content findable and makes you more visible.”

The aging of resources effect follows a previous finding by complex network researcher Albert-László Barabási of the University of Notre Dame, which found that information stays fresh on the Web for only about 36 to 48 hours. Similarly, the researchers found that users on collaborative tagging sites would likely prefer recently added tags to older ones.

Barabási, whose work focuses more on the entire World Wide Web, applauds the Italian researchers for being the first to address the new phenomenon of collaborative tagging and attempting to demystify its behavior. “They are taking a new technology, which kind of enhances the usage of the Web and the underlying network structure—and they use quantitative methods to understand its properties,” he says. “This paper probably will not tell you what’s going to be the coolest term, but it will tell you what the fundamental structures within the system.”

When It’s O.K. to Run Hurt

 

NY Times – It sounds almost like heresy. The usual advice in treating injuries is to rest until the pain goes away. But Dr. Weinstein and a number of leading sports medicine specialists say that is outdated and counterproductive. In fact, Dr. Weinstein says, when active people consult him, he usually tells them to keep exercising. The idea, these orthopedists and exercise specialists say, is to use common sense. If you’ve got tendinitis or sprained a muscle or tendon by doing too much, don’t go right back to exercising at the same level. The specific advice can differ from specialist to specialist. Some say most people can continue with the sport they love although they may need to cut back a bit, running shorter distances or going more slowly. Others say to cross-train at least some of the time and others say the safest thing to do is to cross-train all the time until the pain is gone.

“We want to keep you moving,” said Dr. William Roberts, a sports medicine specialist at the University of Minnesota and a past president of the American College of Sports Medicine. “Injured tissue heals better if it’s under some sort of stress.” Small repeated stretching of tendons that are already inflamed leads to the production of molecules that heal inflammation. That suggests moderate exercise can actually speed healing. He and others acknowledge that the advice to keep moving may come as a surprise and that some doctors feel uncomfortable giving it, worried that their patients will do too much, make things worse and then blame their doctor. “The easy way out is to say, ‘Don’t exercise,’ ” said Dr. Richard Steadman, an orthopedic surgeon in Vail, CO. That advice, he added, “is safe and you probably will have healing over time.” But, he said, “if the injury is not severe, resting it will probably prolong recovery.”

Dr. Weinstein’s advice for injured patients is among the boldest — he said it’s based on his basic research and his own experience with sports injuries, like knee pain and tendinitis of the Achilles and hamstring. Before exercise, he said, take one anti-inflammatory pill, like an aspirin. Ice the area for 20 minutes. Then start your usual exercise, the one that resulted in your injury, possibly reducing the intensity or time you would have spent. When you finish, ice the injured area again. The anti-inflammatory pill should forestall new inflammation from the exercise that is about to occur. The icing is to constrict blood vessels before and after exercise, thereby preventing some of the inflammatory white blood cells from reaching the injured tissue.

Frontline: The Other Drug War

Frontline PBS: Through interviews with consumers, legislators, scientists, top industry leaders and analysts, “The Other Drug War” explores the tension between the high cost of scientific innovation and society’s need to keep drugs and health care affordable.

A wonderful site with a great deal of information. Addresses issues such as: Will controlling the prices of prescription drugs hinder innovation? What would happen if the U.S. instituted price controls on prescription drugs? Pros and Cons of drug advertising and marketing.

The Key to Heart Health from Wine

Scientific American: Wine’s beneficial effects on heart health depend more on the traditional vintner’s art than the wonder molecule resveratrol. Resveratrol, a molecule found in the skin of red grapes, among other places, has been found to have a host of health effects, most recently prolonging the life spans of obese mice. But the natural wonder drug does not play a role in the beneficial effects of wine drinking, according to research published in the November 28 issue of Nature. “There are some fascinating effects of resveratrol in animal systems,” notes plant biochemist Alan Crozier of the University of Glasgow. “To get similar doses into humans through red wine, you would have to consume more than 1,000 liters of red wine a day.” Because drinking that much wine is beyond even the hardiest oenophile–yes, even those in France–Crozier and his colleague Roger Corder of Queen Mary’s School of Medicine and Dentistry in London set out to identify exactly the compounds in red wine that promote heart health. Using the endothelial cells that line human artery walls, the researchers tested which compounds in wine had the greatest effect. The tests showed that flavonoids called oligomeric procyanidins–essentially condensed tannins, the compounds that impart bitterness to young reds–suppressed production of the peptide responsible for hardening arteries.

Using French census data, the two researchers then compared regions that had unusually long-lived men with the wine produced in those areas. The Nuoro province of Sardinia and the Gers region of southwestern France both support relatively more men who survive past 75 years of age. Not coincidentally, these regions also produce local wines that are as much as four times richer in procyanidins than other wines. Traditional wine-making techniques proved key: by allowing the grapes to linger on the vine for as long as possible and then leaving them to ferment for as long as four weeks (compared with the more typical one-week period of major wineries, which keeps the level of harsh tannins low), vintners in these regions produce prodigious amounts of procyanidin. Also crucial are the type of grape involved (Tannat in Gers, a small, seedy fruit rarely grown outside the southwest of France) and the elevation at which it is grown (ultraviolet helps catalyze the production of procyanidins in the high-elevation vineyards of Sardinia). Of course, understanding exactly how procyanidins work in the human body remains to be investigated, and the researchers plan to dose people with the compound in a future clinical trial. In the meantime, a few glasses of wine–particularly a full-bodied one–remain a recipe for a stronger heart.

Cancer Prevention Diet…I’m Skeptical

The Boston Globe: It is time to reconsider the whole idea that the public ought to change its diet to help prevent cancer. The cancer prevention diet was launched on inadequate scientific evidence almost 25 years ago. Now five different randomized clinical trials have evaluated the preventive power of various recommended foods or ingredients, and not a single one has found a measurable effect. Rare is the adult who has not head the message from the National Cancer Institute that to lower the risk of cancer, people ought to eat five servings a day of foods with high fiber, low fat and containing fruit or vegetables. This dietary advice was publicized extensively with millions of dollars from the fruit and produce industry, which was hoping to increase market share for its products.

The larger lesson, however, is that the diet and cancer story proves how easy it is for health authorities to give dietary advice and the eagerness with which the public embraces it despite the shaky scientific foundations of the whole enterprise. Of all the key aspects of health, diet may be the most difficult to study. We eat different foods at every meal, and diet varies greatly day by day. Most of the food we eat is either excreted or heavily processed in the human chemical factory and reduced to basic compounds such as sugars, trigylcerides and lipids. To make matters more difficult, the exact same food item can have quite different effects when consumed as a liquid, a solid or mixed with other foods. With some ingredients such as sodium and calcium, the body tightly regulates concentrations within narrow limits using powerful biological mechanisms to dispose immediately of any surplus. Only dire shortages or gross excesses overwhelm this system–and these can be life threatening but are quite rare.