Archive for October, 2010

What's an obese person going to do now?

Friday, October 29th, 2010

It's not surprising to me; the drug Qnexa wasn't approved by the FDA for use in weight loss. Why not? After all it's a combination of low doses of two medications that are already approved. Phentermine was first approved by the FDA in 1959 and for weight loss even, although we're talking short-term use in combination with dieting. The other drug, topiramate, was approved in 1996 for epilepsy and more recently for prevention of migraines.

I hadn't heard of Qnexa when I saw the article in the New York Times yesterday, but today I've had time to look at it's pros and cons and put the risks in perspective.

Qnexa is made by a company called Vivus; their stock went up 28.06% today; I guess that was in anticipation of the medication being approved. When I looked at the company's website, they detail the problem of obesity. It's a major factor in diabetes type 2, high blood pressure, cardiovascular disease and stroke. Some have called it the second leading cause of preventable deaths in America.

Over 400 million people worldwide are obese and it's said to be responible for 9.1% of the annual US healthcare spending; that nearly 150 billion dollars.

And Qnexa has gone through Phase 3 trials on over 4,500 patients with three trials. Its results were impressive; one article mentioned a 14.7% (37 pound) weight loss over a 56-week period. Another controlled trial result said 10.6% compared to 1.7% for those who got placebos.

So why not approve the drug? Well, the answer lies in what pre-clinical and clinical trials do and don't show.

Let's start with Phase Zero through III. Those are conducted with human subjects, initially with tiny doses looking at how the body processes the drug and how it works, progressing to is the drug reasonably safe and tolerable studies with small groups closely observed. Then we go to larger groups for activity and safety and finally to randomized controlled multi-center studies.

At that point the dug may be approved, but, there is Phase IV, post marketing surveillance. That is to detect rare or long-term adverse effects in much larger groups of patients.

Several drugs have been withdrawn or subjected to limited use in Phase IV.  There have been some risks shown in early trials; millions of people would potentially take the drug if it were to be approved. Side effects would conceivably be greater and more serious than smaller studies have shown. Lots of lawsuits could result.

So it's not just the name of the drug being hard to pronounce (who came up with Qnexa?).

I suspect the medication may eventually be approved, but time will tell.

Calcium supplements, heart attacks and statistics

Tuesday, October 26th, 2010

After I looked through the November issue of the Harvard Heart Letter I decided to revisit the calcium supplement issue I wrote about several months ago.

Harvard researchers published an article in Annals of Internal Medicine in March of this year. They did a meta-analysis of 17 studies that examined results from calcium supplementation, or vitamin D supplementation, or both, with an emphasis on cardiovascular disease (CVD). A meta-analysis statistically combines the results of several studies that address a shared research hypotheses.

A friend gave me Tom Siegfried's article on statistical significance from the March 27, 2010 edition of Science News. It's title is "Odds are, it's Wrong." What it basically said was our way of deciding if a conclusion is valid is flawed much of the time. We really often need to examine the results of several studies and then see if the studies were actually designed to look at the general population.

We also need to examine at the level of confidence in the results. The standard we most often use is a p value of 0,05; that translates as one possibility in twenty that a result happened by chance. Is that good enough? I'd be very comfortable if the possibility was one in ten thousand, but one in twenty? A later comment in the same journal added casuality, e.g, Although 100% of people who die of stomach cancer drank milk as kids, that doesn't mean milk causes stomach cancer.

So let's go back to the Harvard paper and see how it applies to you and me. The Harvard folk started with 1,484 possible articles and came up with only17 that met their criteria. They wanted to limit their included research projects to prospective controlled studies in adults. They excluded, among others, review articles, letters to the editor, papers where there was no control group, retrospective studies or studies in children.

So far, so good. But when I drilled down into the remaining articles, many were done on dialysis patients, not a general population. Some were projects were only vitamin D was taken, some where just calcium was given, some where both were supplemented.

In terms of the general population they only found one study where just vitamin D was taken by the participants.  Even that one was flawed; it didn't include sufficient information on sun exposure or duration of vitamin D supplementation. It did conclude that postmenopausal women (34,486 of them), not only didn't increase their CVD risk by taking vitamin D; they likely decreased it. Other studies I've ready recently aren't as sure of the cardiovascular benefits of vitamin D.

We really do need vitamin D; it helps us absorb calcium and has other roles including maintaining healthy bones.  The NIH says most healthy adults can safely take vitamin D in doses up to 2,000 IU/day, The Harvard Heart Letter said 800 to 1,000 IU/day.  Sun exposure is the other place we get it, 10 to 15 minutes a day without sunscreen is enough.

The New Zealand article, published in the British Medical Journal in August 2010, said there was a 30% increase in cardiovascular events in people taking calcium supplements. But...the increase in heart attack frequency was one person in 200. Additionally their study excluded anyone also taking vitamin D; that makes less sense to me. The only study reviewed by the Harvard researchers that looked at combined calcium and vitamin D supplements showed no increase in CVD risk.

So I'm still not taking calcium tablets, but I am drinking skim milk (low-fat is another choice if you hate skim milk) and eating some non-fat yogurt daily. And I'm taking vitamin D.

Healthy School Snacks

Friday, October 22nd, 2010

I read an interesting article in the Wall Street Journal yesterday and then perused lots of background information on the Web. The article itself described the challenges of designing a vending machine that could dispense healthier snacks, especially for schools. I had heard that many school districts and even some states were concerned about the obesity epidemic and wanted to quit offering candy bars and sugared sodas. It's not that easy.

One company now offers a vending machine with two major compartments, one for bananas and the other for fresh-cut fruits and veggies. The banana compartment is kept at 57 degrees and the other area at 34 degrees.  They're working on the issue of keeping the fruit, especially the bananas, from getting bruised when it's selected and falls to the delivery area.

The Center for Science in the Public Interest has a website which I found by Googling "Healthy School Snacks." They noted that over a nineteen-year period (1977 to 1996), our kids' calorie consumption from snacks had increased by 120 calories per day. That's roughly equivalent to a ten pound a year weight gain.

They estimated that cost of serving fresh, frozen or canned fruits and veggies would be about 25 cents a day. That's a lot less than their estimates for single-serving bags of potato chips at 69 cents or candy bars at 80 cents.

They gave some suggestions for kid-friendly snacks, including a clever recipe for "Ants on a Log." made by spreading peanut butter on celery sticks and adding raisins.

Then I found the December 2009 Massachusetts Food and Beverage Standards to Promote a Healthier School Environment. They mention the national Action for Healthy Kids (AFHK) initiative ( That website is well worth looking at, but I concentrated on the Massachusetts plan itself.

A survey done in Massachusetts in 2005 showed over a quarter of students at risk for overweight or already overweight. So state officials and a bevy of advisors were concerned about so-called "competitive foods," which often are high in fats and sugars.  These are sold in vending machines, in school stores or in fundraisers and compete with the well-regulated school lunch and breakfast programs.

Now the state has published a set of well-reasoned guideline for various foods and beverages that might be offered in the schools. The John Stalker Institute website has links for the information.

Take a look, whether you have kids or grandkids in school or not. We need to get behind efforts like this. Adults may be set in their eating habits and reject sound advice; school kids are a captive audience in a sense and their lifetime eating habits can be influenced for their good.

Does sleeping longer help us lose more fat?

Wednesday, October 20th, 2010

I read an intriguing article in the 5 October, 2010 edition of Annals of Internal Medicine, then saw the accompanying editorial. The article was titled "Insufficient Sleep Undermines Dietary Efforts to Reduce Adiposity" and was densely scientific, even for me; the editorial was titled "Sleep Well and Stay Slim: Dream or Reality." I decided to start with the commentary and then return to the study itself.

Having read both in detail, I'm comfortable with what's said and what the limitations of the study, done at the University of Chicago and the University of Wisconsin, might be. So let's start there.

The researchers put newspaper ads in local papers to recruit a small number of subjects for a short-term study. They ended up with ten volunteers who didn't smoke, were overweight, but otherwise healthy. The study protocol was detailed ,but basically each of the subjects was on a two-week diet with eight hours or sleep and another similar period with five and a half hours of sleep.

They lost similar amounts of weight in both study periods, but lost more fat during the time they when they dieted and slept well. So sleeping less and dieting resulted in the loss of "fat-free body mass." In other words they lost more fat and less muscle when they slept longer and vice versa when they slept less.

How does this apply to the rest of us? Well there is some data linking a decreased sleep duration with an increase in obesity rates in larger groups. There are rodent studies supporting the theory. There are some larger human studies showing shorter periods of sleep are associated with changes in two hormones that affect appetite and one that showed an association between snacking and less sleep.

So there's a lot of data accumulating that strongly suggests, but does not yet, from a strictly scientific point of view prove, that if we need to lose fat we should diet and also get adequate amounts of sleep.

It makes sense to me. I wouldn't hold my breath waiting for large studies in general populations that confirm this small-scale research. We are a chronically under-slept nation, a number of sources have proclaimed, and I think they're right.

So cutting your hours of sleep while you diet appears to be self-defeating and sleeping a full eight hours, give or take a little, is probably better if you want to lose fat.

Walmart weighs in on local produce

Friday, October 15th, 2010

Let me start with a disclaimer. I don't have any personal connection with Walmart and I'm aware of the issues that unions, small locally-owned stores and others have had with the corporation. We rarely even set foot in our local Walmart mega-store.  We do have a Sam's Club card and occasionally buy something there, but do most of our non-CSA grocery shopping at another chain entirely.

We've continued to get the majority of our veggies and fruits from our CSA, Grant Family Farms. The organic produce, mostly grown locally, or in the case of apples, regionally has been wonderful. On the other hand, I've been fully aware we're in a minority. There are lots of people who could afford the extra price, but have never tried farmers' markets. Others don't have access to a CSA organization. Many more wouldn't be able to afford the prices even if they wanted to purchase these kinds of groceries. I've seen articles implying governmental support would be needed before this happened.

I doubted that was likely to occur, but wondered if one of the huge grocery chains could start the process of giving making healthier choices available for almost anyone. Now that seems to have started.

A article in the October 14, 2010 edition of the New York Times gave me some measure of optimism in this arena  and some background information that I was unaware of.

Walmart is the world's largest grocer. What it does can influence markets and manufacturers across the  globe. That being said, up until now I hadn't heard much that linked the chain with sustainable agriculture.

Apparently Walmart has been edging toward sustainability goals for five years and set a series of these targets. Now they're turning their sights toward food with a goal of doubling the percentage of produce grown in a given area, actaully the same state a given store is located in.

Still they are only aiming at a 9% local foods goal in the United States. That's a sliver, a nice sliver to be sure, but they're already set much higher targets in Canada (30% by the end of 2013 according to the article).

They're also planning to spend a billion dollars on food from farms much smaller than the enormous ones most of their groceries come from now, cut down on food waste by improving their farm to market shipping patterns, and query their large-scale producers on their use of water, fertilizer and chemicals. There's even a beef-purchase clause in their new plan that is aimed at prevention of further loss of the Amazon forest.

All this will result in more money in the Walmart coffers, but I don't care. They have such incredible clout, on such a wide scale that their new goals will influence agricultural and marketing practices in a major fashion.

It's a good start.

Do your genes determine the size of your jeans?

Tuesday, October 12th, 2010

An article in the the October 10th edition of the journal Nature Genetics looked at the overall body mass index, BMI (a height to weight ratio that's is commonly used to determine if you're lean, overweight or obese), in nearly a quarter of a million people. The researchers involved in these studies found a number of genes, nearly half of which were previously unknown, linked to obesity.

This news doesn't translate well into common English for most of us, even those of us who've been involved in medicine for most of our lives. So let's go a step or two into what is actually going on.

We all know people who seem like they can eat anything and not gain weight; most of us also know others who say they 'eat "like birds" and just can't lose weight.

Many of the genes that have been linked to obesity seem to play a role here, both in terms of how much we eat (appetite regulation) and how we burn calories (energy balance). Does that help us solve who is going to become obese and who isn't?

One obesity guru commenting on the article relating to BMI said asking patients if their parents were obese or not is a more accurate predictor of that person's  person's likelihood of obesity than all the genetic information in these studies.

Another was quoted as saying the information obtained by all this genetic information is little better "than a flip of (a) coin" in predicting someone's risk of becoming obese.

So I think these studies are important, but suggest you don't rush out to get a DNA analysis. We're a long ways from being able to use this information clinically. If someone recommends you get a lab test based on this new data, they're probably going to make money from the test and you're probably not going to find out anything that will help you lose weight.

I've done basic science research, in my case many years ago, and it's critically important to the advancement of knowledge. But it usually doesn't give us direct answers to real-world problems, at least not immediately.

We've got physicians and researchers from other disciplines exploring obesity in detail. Let's applaud their work and support their studies.

But wait for the breaking news before opening your purses and wallets.

Food Stamps and Obesity

Thursday, October 7th, 2010

In 2004 the state of Minnesota tried, unsuccessfully, to ban the purchase of "junk food" with food stamps. The request was eventually denied by the USDA on rather strange grounds, that it would "perpetuate the myth" that food-stamp users made bad choices in their grocery shopping.

In the meantime the obesity epidemic in the United States rolled on and now, in an article in today's New York Times, I read that the mayor of New York City has asked the federal government for permission to stop food-stamp recipients from purchasing sugared drinks, sodas, of course, being the major culprit in this case.

I'm waiting for the answer, but my bet is the request is denied, although we already, according to the article, ban the use of food stamps to purchase other items that can be health-detrimental, especially cigarettes and alcoholic beverages. The beverage industry will obviously lobby against the plan.  Even the Center for Science in the Public Interest, a non-profit consumer advocacy group with a focus on nutrition and health, food safety, and alcohol policy, suggested we should instead use educational programs to teach food-stamp recipients about the dangers of sugared drinks.

So is Mayor Blomberg in favor of a Big Brother era? He already has lobbied for a state tax on sugared drinks (unsuccessfully), tightened rules on food advertising and brought the city's schools a tougher policy on which food items they can sell.

Yet almost 40% of the kids in NYC's public schools at the K-8th grade level are overweight or obese, with rates still higher in poorer areas of the city. In those same neighborhoods, studies are said to show sugared beverages are consumed at higher rates than in leaner sections of the metro area. Diabetes is twice as prevalent in poor areas of NYC as it is in more affluent ones.

So where do we stop? I totally agree that we're at a crisis point as a society, one fueled by the food industry. I personally deplore the use of food stamps to purchase sugared beverages as much as I do their being used to procure cigarettes and alcohol-containing drinks.  But who gets to decide what our choices are in a free society?

Tough questions without easy answers.

Don't let your burger bug you

Sunday, October 3rd, 2010

Holstein cowThere was an interesting article in the Wall Street Journal yesterday. I read it, decided it good material for my blog and then hunted for background information. The title was "Beef Safety Tests aren't Being Used." It said there were a number of dangerous strains of E. coli in addition to the O157:H7 variety that thousands of people get sick from each year.

That one is well known, causes over 36,000 illness, 1,100 hospitalizations and 30 deaths a year. Our government agencies do test for that strain, but not all possible measures to reduce it are being used.

beef hamburgerFor instance at the huge Cargill plant at Fort Morgan, Colorado, every lot of ground beef has been tested for E. coli O157:H7 before it leaves the plant. Workers take 60 to 75 samples per 2,000-pound to 10,000-pound lot. The meat isn't shipped until it gets the all-clear, a process that takes about 18 hours.

That's pasted in from an article I found on beef testing; I'm amazed at the size of the lots and not overly impressed by the sampling. Cargill is also vaccinating cows for that E. coli strain, but giving two shots instead of the three that testing showed reduced the prevalence of the bacteria by  86% (two shots are cheaper than three, but only 50-60% effective).

They're also trying out some newer methods to cut the prevalence of that E. coli strain.

Then there is Kevin's law.

In 2005, Representative Anna Eshoo of California proposed this regulation nicknamed after a Colorado boy who died in 2001 after eating a hamburger contaminated with O157:H7. It was formally titled the Meat and Poultry Pathogen Reduction and Enforcement Act of 2003.

Kevin's Law would strengthen the U.S. government's ability to prevent contaminated meat and poultry from entering the food supply by:- Requiring the United States Department of Agriculture (USDA) to identify the pathogens that threaten human health (e.g. Salmonella, E. coli O157:H7, Listeria monocytogenes).

- Requiring the USDA to establish performance standards to reduce the presence of these pathogens in meat and poultry.

- Confirming that the USDA has the authority to enforce its own standards by shutting down plants that continually breach basic health standards. Courts have held that the USDA does not have this authority in the absence of explicit authorizing legislation.

Corporate meat processors have lobbied against Kevin's Law, arguing that it would increase the cost of food and is unnecessary.

Versions of the bill have been introduced in each subsequent Congress, but as of April 2010 have never been reported out of committee.

Now government officials say there are six E. coli strains that can be just as dangerous. One of those is E. coli O26 and there is a test for that and three of the others, but the USDA doesn't routinely use them. They did recall 8,500 pounds of raw ground beef that was found to be contiminated with E. coli O26 this year.

There's lots more to say on this subject, but I'll do so in a later post. For now it's suggested that you really cook your hamburgers; they shouldn't be at all pink inside. I used to eat rare hamburgers; I sure don't now.