Meridia Withdrawn from US Market

… or, So Long Sibutramine Over two thirds of Americans are overweight.  A safe and effective medication that helps people lose weight would be a boon for the health of millions who are struggling to take off the pounds.  Unfortunately, this has been an extremely tough nut to crack for the pharmaceutical industry. The existing medications for weight loss have been only modestly effective, and last week the choices became fewer.  Meridia (the brand name of the medicine sibutramine) was voluntari...
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Sleep Deprivation Sabotages Dieting

The correlation between obesity and inadequate sleep has been known for some time.  But does one cause the other or are they coincidental?  It’s also known that inadequate sleep increases hunger, an effect I can attest to from my memories of medical training.  I always ate more than usual on the days following nights spent in the hospital. So people who don’t sleep enough feel hungrier and presumably eat more than people who get enough sleep.  Is that the only mechanism connecting poor sleep to...
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Startling Scientific Finding: Dieting Leads to Weight Loss

What sort of diet helps people lose more weight?  Do overweight people lose more weight on a low-carbohydrate diet (like Atkins) or on a low-fat diet (like Weight Watchers and others)? A carefully designed study published in the current issue of the Annals of Internal Medicine answers that question.  The study enrolled over 300 obese adults and randomized them to a low-carbohydrate diet or a low-fat diet.  Importantly, patients with diabetes, high cholesterol and high blood pressure were exclud...
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Rethinking Calcium Supplements

This week I discovered how painful it can be to change a habit.  Not because it means admitting I was doing the wrong thing, but because it means analyzing how feeble my reasons were for the habit in the first place. Ever since I started practice I’ve been recommending calcium supplements to post-menopausal women.  Why?  Mostly out of habit.  There’s not a shred of evidence that calcium supplements prevent fractures, but some suggestion that they may help bone density.  But what’s the harm?  Ca...
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Heavy Coffee Drinkers May not be Getting any Boost from their Caffeine Fix

Everyone knows that caffeine is useful on occasion if we need to stay alert, especially when we’re sleepy.  Is there any college graduate who hasn’t had a caffeine-fueled all-night study session before an exam?  I certainly remember several nights in which I drank coffee to the point of inability to blink, much less sleep. But for those who drink a lot of coffee daily, how much of a boost in alertness are they getting?  A study in this issue of Neuropsychopharmacology offers an interesting insi...
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A Dietitian’s Thoughts on Diet Sodas

Two weeks ago I wrote a post about the mistake we make when we think of some medicine or food as generally “good for you” or “bad for you” as opposed to having specific benefits and harms.  I started with an anecdote in which a friend asked me whether diet sodas or regular sodas were better for you. Susan Dopart, a terrific dietitian who I’ve known for over a decade, emailed me to bend my thinking about diet sodas and about non-nutritive...
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Gastric Banding is an Effective Option for Obese Teens

What’s my advice to my overweight patients?  Eat less and exercise more.  I give this advice every day, but following this advice is much harder than giving it.  Overweight people frequently struggle with diet and exercise for years, sometimes successfully, sometimes regaining their previously lost weight. And as we become more overweight as a nation, obesity is no longer just a problem for adults.  Over 5 million adolescents are estimated to be obese in the US, which predicts bad things for th...
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Normal Weight Obesity: Why Losing Weight Is Not Always the Answer

Weight loss is one of the most common recommendations that doctors make.  How do we know if a patient should lose weight?  We usually use the Body Mass Index (BMI) which is a way to compare a patient’s weight to her height.  (For all you math geeks, it’s the weight in kilograms divided by the height in meters squared.  For all you physicists, I know the units make no sense.)  A BMI of 18.5 to 25 is considered normal.  A BMI of 25 to 30 is considered overweight, and over 30 is considered obese.  ...
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Mollified about Mercury (or Calm about Catfish)

Mercury in high doses is known to be toxic.  So if you were thinking about breaking your glass thermometer and drinking the contents on a lark, I beg you to reconsider.  This has raised concern about possible harm from eating seafood since many species of seafood are known to contain trace amounts of mercury.  Much hand-wringing has ensued.  Should we shun salmon?  Avoid albacore? The most recent issue of The Medical Letter, a publication I frequently cite, summarizes the scientific literature ...
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Folic Acid: Fabulous for Fertile Females, Feckless for Fellows

Folic acid, a vitamin found naturally in green leafy vegetables and legumes, is essential for making the building blocks of DNA.  And since copying DNA is an important part of what cells do before they divide, it’s critical for cell division.  Developing fetuses have very rapidly dividing cells, so it’s not surprising that folic acid deficiency has been linked to birth defects, specifically brain and spinal cord abnormalities. To prevent these birth defects, physicians for many...
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