The FDA recently approved the first weight-loss drug, Belviq (lorcaserin hydrochloride), in 13 years.  Arena Pharmaceuticals of San Diego developed the pill to help people lose 3-4% of their body weight when coupled with exercise and a healthy diet.  The FDA approved the pill for obese people (BMI over 30) and some overweight people (BMI over 27) who suffer from high blood pressure, high cholesterol, and type 2 diabetes.

Potential weight-loss drugs face increased scrutiny tod
ay by the FDA for efficacy and safety as many recent ones (fenfluramine, for example) have been recalled due to heart-valve complications.  In March, the FDA’s advisory committee introduced mandatory tests for cardiovascular risks for all obesity drugs, which makes the current clinical trials even longer.

In 2010, Arena applied for approval of the drug. The FDA denied approval because it was deemed responsible for causing tumors in rats and because it could not definitively rule out an increase in heart-valve defects.  The pharmaceutical company conducted echocardiograms for 8,000 patients to determine heart-valve function.  This trial could not verify an increase in heart-valve defects in the users of the drug, convincing the FDA to approve it.  The company committed to perform six post-marketing studies with a long-term cardiovascular trial that will search for heart attack and stroke risks.

The drug works to suppress food cravings by mimicking the effects of serotonin in the brain.  Along with many other vital functions, the neurotransmitter serotonin plays a role in controlling appetite.  Within the brain, neurons pass messages back and forth using chemical messengers (neurotransmitters).  The messages may involve information concerning emotions, body temperature, behavior and appetite.  The specific kind of information delivered varies with which neurons become activated and where the brain becomes stimulated.  The neurotransmitter leaves the neuron and enters the synapse (the space between the two “communicating” neurons).  The neurotransmitter links with the receptor on the other neuron, which sends the message.  This can then be repeated through a process called reuptake.  Serotonin qualifies as a neurotransmitter.  The drug Belviq mimics serotonin by activating the 2C receptor, which increases the amount of serotonin to carry messages and increases the probability that the message is received.  Thus, the drug causes people to eat less and feel full.

Non-diabetic patients reported headache, dizziness, fatigue, nausea, dry mouth and constipation as side effects.  Other side effects include serotonin syndrome especially in combination with depression or headache medication that increase serotonin levels or that activate serotonin receptors.  The drug may also affect attention or memory.  In diabetics, side effects include low blood sugar, pain, cough and fatigue.

On average, a 198-pound patient taking Belviq will lose six to seven pounds in a year.  20% of patients lose at least 10% of their body weight.  Comparatively, 47% of patients without type 2 diabetes taking the drug and 23% of those taking a placebo each lost at least 5% of their total body weight.  38% of patients with type 2 diabetes taking the drug and 16% of those taking a placebo each lost at least 5% of their total body weight.  Type 2 diabetics who toke Belviq proved to be twice as likely to regulate their blood sugars compared to those who toke the placebo.

While it may help those suffering from diabetes, it may cause heart complications.  The company advises patients with congestive heart failure or pregnant patients to not take the drug.  CNN’s Dr. Melina Jampolis, a physician nutrition specialist and diet and fitness expert, calls the results modest and says, “But most experts agree that even a 5% weight loss has significant implications in terms of reducing the risk of obesity associated diseases including heart disease and diabetes.”

The drug may be risky, but risks also come with the rising obesity rate such as diabetes and heart disease.  With more than 1/3 of the adult population being obese, the drug may prove worthwhile.

Sources

Nature

CNN

Recently Miley Cyrus has been touting a gluten free diet as a way to lose weight.   Is this true or just another celebrity fad? Gluten is a protein present in foods including wheat, rye, oats, and barley  but may also be found in everyday products such as medicines, vitamins, and even lip balms.    There's absolutely nothing wrong with eating gluten unless you have celiac disease, or gluten sensitive enteropathy (GSE), an autoimmune disease that damages the small intestine and interferes with absorption of nutrients from food. If you are sensitive to gluten, the body produces an abnormal immune response to it, attacking the lining of small intestine where digestion takes place. This leads to the symptoms of celiac disease: • abdominal bloating and pain • chronic diarrhea • vomiting • constipation • pale, foul-smelling, or fatty stool • weight loss About 1% of the population has GSE. But there may be another 9% or so who have what is called gluten sensitivity or gluten intolerance. These people may have similar symptoms to those with GSE but do not show the same damage to the bowel as those with GSE. The only treatment for celiac disease is a lifelong, gluten-free diet.  But can it cause you to lose weight?  The answer is complicated.  Studies have shown that patients with GSE who were underweight gained  weight on a gluten-free diet. Those with GSE and obesity tended to lose weight after starting a gluten-free diet. What about people who don't have GSE? Celebrities have touted a gluten-free diet as a way to lose weight. Proponents hype it as a healthier way to eat. They claim it improves sleep, increases energy, and clears skin. Some go so far as to say it helps those with autism and rheumatoid arthritis. But Dee Sandquist, MS, RD, a spokeswoman for the Academy of Nutrition and Dietetics, who also happens to have celiac disease, says:   There is nothing magical about eliminating gluten that will improve your health or enhance weight loss unless you are intolerant to gluten.   The academy points out that "Research on individuals with celiac disease reports that long-term compliance with a gluten-free dietary pattern improves outcomes related to bone density, iron deficiency anemia, villous atrophy, gastrointestinal and neurological symptoms, pregnancy outcomes and quality of life." One problem is the fact that many people with GSE don't even know that they have the disease, and those with gluten intolerance are less likely to be diagnosed.  Researchers conclude that there is no scientific evidence supporting the alleged benefit that a gluten-free diet will promote weight loss and  that adherence to the gluten-free dietary pattern may actually result in a diet that is low in carbohydrates, fiber  and important vitamins. Many confuse a gluten-free diet with a low-carb diet (which can promote weight loss).     A gluten-free diet eliminates foods such as bread and pasta, it doesn't eliminate other high-carb foods such as rice, beans and corn.    The popularity of gluten-free diets has lead to an explosion of gluten-free food availability and a financially growing industry that  is expected to exceed $5 billion by 2015! This is great if you need to be on the diet. However, people need to be aware that these are not low-calorie foods! Some prepared foods have additional fat and sugar added and mixed into substitute flours such as white rice flour or potato starch to make them more palatable. A gluten-free diet is not a panacea for weight loss. It is, however, an important diet for those who suffer from GSE or intolerance.

The Old--remember these?

Remember those weight loss machines that consisted of a vibrating belt you put around your waist?   They were often part of a comedy routine on early TV.  Well,  they are back in the form of a whole body vibration machine.

With the new whole body vibration, you stand, sit or lie on a machine with a vibrating platform. As the machine vibrates, it transmits energy to your body, forcing your muscles to contract and relax dozens of times each second. (The old version only shook the belt)  You may feel as if you're exerting yourself when you do whole body vibration. You can find a whole body vibration machine at a local gym, or you can even buy one for home use.

The New --Whole Body Vibration Machine

Advocates say that as little as 15 minutes a day of whole body vibration three times a week can aid weight loss, burn fat, improve flexibility, enhance blood flow, build strength and decrease the stress hormone cortisol.   But comprehensive research about whole body vibration is lacking. It's not yet clear if whole body vibration provides the same range of health benefits as exercise you actively engage in, such as walking, biking or swimming. Some research does show that whole body vibration may help improve muscle strength and that it may help with weight loss when you also cut back on calories.

One of the selling points of this machine is the belief that it may increase bone mineral density and thus help prevent osteoporosis.  But a new study does not support this hypothesis.

A year of whole-body vibration (WBV) did not alter bone mineral density (BMD) or bone structure in postmenopausal women taking vitamin D and calcium supplements, Canadian researcher Angela Cheung, MD, and colleagues from the University Health Network in Toronto reported.

"Whole body vibration has been introduced in the past decade as a promising new anti-osteoporotic therapy, because significant improvements in bone formation, BMD, and cortical thickness were found in animal models," wrote the authors.   "Although commercially available WBV devices are marketed to and used by patients," they continued, "the beneficial effects of WBV on fracture risk and BMD have not been established, and recent randomized, controlled trials in postmenopausal women have shown conflicting results."

To clarify the issue, the researchers studied healthy postmenopausal women with BMD T-scores between -1.0 and -2.5 who were not prescribed bone medications. (A T-score between +1 and −1 is considered normal or healthy. A T-score between −1 and −2.5 indicates that you have low bone mass, although not low enough to be diagnosed with osteoporosis. A T-score of −2.5 or lower indicates that you have osteoporosis. The greater the negative number, the more severe the osteoporosis). Patients were randomly assigned to three groups: two groups were asked to stand on a low-magnitude WBV platform for 20 minutes daily, and the third group served as the control group.

The groups did not differ in the number of clinical fractures during the period.  None of these fractures that did occur were  related to frailty because they were caused by car, household, or sporting accidents or involved only the small bones of the foot.

"[Twelve] months of low-magnitude WBV at either 90- or 30-Hz had no effect on BMD or bone structure in healthy, community-dwelling, postmenopausal women who received calcium and vitamin D supplementation, and thus is not recommended for preventing age-related bone loss in this population," wrote the researchers.

Why are some people obese while others are lean? Obese people must make poor eating choices, but could there be a physiological basis for those poor choices? A new study reveals that obese and lean people make decisions about short-term versus long-term rewards differently and have physical differences in their brains. Surprisingly, some of these behavioral and physical differences are found only in women.

An article recently published in the journal Frontiers in Human Neuroscience tested how lean and obese people relate to rewards using a simple card game. In this game, participants had to choose between two decks of cards. One deck provided large immediate rewards but overall losses in the long-term. This deck was meant to parallel the immediate reward of eating and the long-term negative effect of overeating on body weight. The other deck gave subjects smaller immediate rewards but was more advantageous in the long run. This deck represented healthier eating choices – less fulfilling immediately but more beneficial in the long term.

The researchers found that obese women choose immediate rewards more often than lean women. In fact, as the body mass index or BMI of the subjects increased, so did the number of times that they chose from the deck that provided large immediate rewards.

Additionally, as they played this card game over time lean women altered their choices and started to choose more cards from the deck that was advantageous in the long run. In contrast, obese women did not change their decision-making over time and continued to choose just as many cards from the deck that provided large immediate rewards but overall losses as the game progressed.

Remarkably, these behavioral differences between lean and obese participants were limited to women. No difference was seen between lean and obese men.

To investigate the possible basis of the behavioral differences between subjects, the brain structure of lean and obese men and women was examined using magnetic resonance imaging or MRI. Differences in brain structure between obese and lean people have been reported previously. This study found additional differences that were only present in obese versus lean women and not men.

Both the behavior and brain structure of the obese women observed in this study suggest that obese women might make poor eating choices because they are more sensitive to rewards and are driven more by habit-like behavior rather than goal-directed behavior. It is not known, however, if the alterations in brain structure in obese individuals are themselves the cause of obesity and overeating behaviors, or if the alterations are the effect of obesity-related behaviors.

The differences in behavior and brain structure between lean and obese women uncovered in this research could be important for the development of gender-specific treatments for obesity.