Long-term weight loss considered nearly impossible


Here's a CBC science piece quoting several obesity experts argues that long-term weight loss is almost impossible, saying that (uncited) meta-analyses of weight-loss intervention found that in the 5- to 10-year range, most weight-loss was reversed. According to Tim Caulfield, who holds a Canada Research Chair in Health Law and Policy, this is an open secret in scholarly and scientific weight-loss circles, but no one wants to talk about it for fear that it will scare people off of healthier eating and exercise regimes, which have benefits independent of weight-loss.

I found the article frustrating. While I am willing to stipulate that the data on long-term weight-loss suggests extreme difficulty, I wish the journalist had found biologists or doctors to discuss the issue, and had cited actual, specific research to support the claims made, which would make it easier to parse the nuances in the piece. It's not that I think that interdisciplinary lawyers with an undergraduate science background have something to say on this (I am 100 percent for interdisciplinary researchers, especially on complex questions like obesity), and while I think that psychologists like Traci Mann have a lot to say about some dimensions of weight-loss, it would have been great to find out what endocrinologists and other bioscience-types had to say about the phenomenon.

For my part, I went from about 250 lbs to about 170 in 2002/3, by eating a very low-carb diet. This morning, I weighed in at 176 lbs. I attribute my sustained weight loss to daily swimming (which I do for physiotherapy for chronic back pain) and a moderate-carb diet, as well as a two-day-a-week 600 calorie fasting regime.

Which is to say, it's a ton of work to stay where I am, and I know from past experience that if I skip swimming for a few days, or let myself go nuts on carbs for more than a day or two, or skip fasting-days (which aren't really fasting -- just very low-calorie days) that my weight creeps up. I pretty much never eat without making a complex (and tediously unwelcome) calculation about what I'm about to consume, and I often experience guilt while eating "bad" food and shame afterwards.

Clearly, this is less than optimal!

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Scientists still trying to figure out how added sugar affects your health

Here's a crazy fact: Thanks to soda and the sneaky added sugars in store-bought foods, 25% of Americans consume a diet that is 25% sugar. In fact, all it takes to hit that is three cans of soda on top of an otherwise sugar-free diet. What does eating like that mean for your health in the long term? Scientists are still trying to figure that out. Scicurious breaks down a recent study in mice that successfully demonstrates both why our sugar intake has health experts concerned AND why we don't yet know exactly what we're doing to ourselves.

Vegans expose quitters

Raphael Brion: "the website Vegan Sellout List ... is a refined mix of unchecked self-righteousness and threats of actual physical violence." [Eater]

Evolution, pregnancy, and food

The populations at lowest risk for developing gestational diabetes — namely, ladies of European decent — come from cultures that eat (and have eaten, for thousands of years) dairy and wheat-heavy diets that would, normally, increase your risk. Meanwhile, writes Carl Zimmer at The Loom, Bangladeshi women, who have one of the highest risks for gestational diabetes, come from a culture that traditionally ate a low-carb, low-sugar diet. What's going on here? The answer might lie in evolution. It's a particularly interesting read given the ongoing pop-culture debate about whether 10,000 years is enough time for humans to adapt to eating certain foods. This data on pregnant ladies would suggest the answer is, at least in some respects, yes.

Everything you eat is associated with cancer, but don't worry about it

Image: Shutterstock. Fried chicken gave the model in this stock photo cancer of the double chin.

Sarah Kliff at the Washington Post digs into new research out today from The American Journal of Clinical Nutrition. She writes about correlation and causality, and how to read statistics more intelligently.

Snip:

“I was constantly amazed at how often claims about associations of specific foods with cancer were made, so I wanted to examine systematically the phenomenon,” e-mails study author John Ioannidis ”I suspected that much of this literature must be wrong. What we see is that almost everything is claimed to be associated with cancer, and a large portion of these claims seem to be wrong indeed.”

Among the ingredients in question for their purported relation to cancer risk: veal, salt, pepper spice, flour, egg, bread, pork, butter, tomato, lemon, duck, onion, celery, carrot, parsley, mace, sherry, olive, mushroom, tripe, milk, cheese, coffee, bacon, sugar, lobster, potato, beef, lamb, mustard, nuts, wine, peas, corn, cinnamon, cayenne, orange, tea, rum, and raisin.

Now: combine all of them into one recipe and do the study again, I say.

How the sugar industry defends itself against claims that sugar is unhealthy

Happy Halloween! Mother Jones has a video and multi-part "long read" feature with Gary Taubes on how the sugar industry works to fight research that links sugar consumption with chronic diseases. Taubes is the author of "Good Calories, Bad Calories," and is working on a book about sugar.

In "Big Sugar's Sweet Little Lies," Taubes explores the industry's campaign to "frost its image, hold regulators at bay, and keep scientists from asking: Does sugar kill?"

There's a document dump here with internal memos revealing a strategy to safeguard sugar from "opportunists," "pseudoscientists," and "enemies."

Also, "How a Former Dentist Drilled the Sugar Industry," some classic creepy vintage sugar ads, and a timeline of "sugar spin."

Right, then. Enjoy your trick-or-treating!

The infrastructure of longevity — a systems-level perspective of living to 100

I really enjoyed reading a recent story in The New York Times Magazine about attempts to understand extreme longevity — the weird tendency for certain populations to have larger-than-average numbers of people who live well into their 90s, if not 100s.

Written by Dan Buettner, the piece focuses on the Greek island of Ikaria, and, in many ways, it's a lot like a lot of the other stories I've read on this subject. From a scientific perspective, we don't really understand why some people live longer than others. And we definitely don't understand why some populations have more people who live longer. There are lots of theories. Conveniently, they tend to coincide with our own biases about what we currently think is most wrong with our own society. So articles about extremely long-lived populations tend to offer a lot of inspiring stories, some funny quotes from really old people, and not a lot in the way of answers.

Buettner's story has all those elements, but it also proposes some ideas that were, for me, really thought provoking. After spending much of the article discussing the Ikarian's diet (it's low in meat and sugar, high in antioxidants, and includes lots of locally produced food and wine) and their laid-back, low-stress way of life, Buettner doesn't suggest that we'll all live to be 100 if we just, individually, try to live exactly like the Ikarians do. In fact, he points out that other communities of long-lived individuals actually live differently — Californian Seventh-Day Adventists, for instance, eat no meat at all and don't drink, and they live with the normal stresses of everyday American life.

What these groups do have in common, though, is a strong social infrastructure that ties people to each other emotionally and connects individual choices to a bigger community lifestyle.

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Ask science: Does sugar really make children hyper?

"Why aren’t my kids hyper after binging on sugar?" asked Gillian Mayman at Mind the Science Gap, a blog featuring the work of various Master of Public Health students from the University of Michigan.

The punchline: "A review of 12 separate research studies found that there was no evidence that eating sugar makes kids hyper."

The post is great, but greatest of all? The animated GIFs used to illustrate it. (via @Boraz)

What you can learn from a chimpanzee's diet

Given the trend lately to look backwards, historically, in search of the ideal human diet, I found this article by Rob Dunn really interesting. Dunn discusses some new research that gives us a better idea of what our closest relatives—chimpanzees and bonobos—are eating out in the wild.

Some of the takeaways fit neatly into the current human food zeitgeist—chimpanzees eat a diverse and varied diet, only consume small amounts of meat, and (for obvious reasons) focus on what happens to be in season and available. But some of the information is less apparently applicable to us. For instance, chimpanzees fracking love figs. In fact, different species of figs make up nearly half of all the food the chimpanzees in the study were eating. Figs, people. Can't get enough of 'em.

But the larger point, Dunn writes, is that we can't really apply any of the facts about chimpanzee diets directly to ourselves in a "Just So Story" sort of way. Geography, resource availability, and culture don't work like that. Neither does biology.

You are unlikely to eat like a chimpanzee eats. If you are the average American, you eat more meat and more simple sugar. You eat differently because of choices you make and choices our societies have made (e.g., to produce huge quantities of the foods that most simply satisfy our ancient urges). You also eat differently because the species around you are different, unless you happen to own a greenhouse specializing in tropical African trees.

But even if you were to abandon agricultural food and move into a forest in Tanzania you would still not eat exactly like a chimpanzee. By most reports the food chimpanzees eat tastes bad, at least to humans, (though, one hopes, not to chimpanzees). By some accounting the food chimpanzees eat is also insufficient to keep a human alive and fertile.

Read the rest of the story at Scientific American blogs

Via Mariette DiChristina

Image: Female chimpanzee eating banana, a Creative Commons Attribution Share-Alike (2.0) image from dkeats's photostream

Gweek 053: Fitness for Geeks

Click here to play this episode. Gweek is Boing Boing’s podcast about comic books, science fiction and fantasy, video games, board games, tools, gadgets, apps, and other neat stuff.

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Is responding to food as a reward the same thing as food addiction?

We've had a couple of posts recently about a hypothesis that links the current increase in obesity with an increase in easy access to foods that are designed to trigger reward systems in the human brain. Basically: Maybe we're getting fatter because our brains are seeking out the recurrent reward of food that makes us fat. Scientist Stephan Guyenet explained it all in more detail in a recent guest post.

It's an interesting—and increasingly popular—idea, though not without flaws. To give you some context on how scientists are talking about this, I linked you to a blog post by Scicurious, another scientist who wrote about some of the critiques of food reward and related ideas. In particular, Scicurious questioned some of the implicit connections being made here between body size and health, and eating patterns and body size.

She also talked about another critique, one which came up in a recent article in the journal Nature Reviews Neuroscience. If people are gaining weight because they're addicted to eating unhealthy foods, we ought to see some evidence of that in the way their brains respond to those foods. After all, brains respond to many physically addictive substances in special ways. But we don't see that with junk food. So does that invalidate the hypothesis?

Stephan Guyenet doesn't think it does. In a recent email to me, he explained that he thinks the food reward hypothesis is a bit more nuanced, and can't really be described as "food addiction". At least, not the same way that cigarettes or heroin are addictive.

Addiction is the dependence on a drug, or behavior, despite clear negative consequences. Drug addiction is associated with characteristic changes in the brain, particularly in regions that govern motivation and behavioral reinforcement (reward), which drive out-of-control drug seeking behaviors. Some researchers have proposed that common obesity is a type of “food addiction”, whereby drug addiction-like changes in the brain cause a loss of control over eating behavior. Hisham Ziauddeen and colleagues recently published an opinion piece in Nature Reviews Neuroscience reviewing the evidence related to this idea.

The review concluded that there is currently not enough evidence to treat obesity as a “food addiction”. I agree, and I doubt there ever will be enough evidence. However, this does not challenge the idea that food reward is involved in obesity, an idea I described in a review article in JCEM, on my blog (1, 2), and my recent Boing Boing piece.

The reward system is what motivates us to seek and consume food, and what motivates us to choose certain foods over others. To begin to appreciate its role in obesity, all we need is a common sense example.

Why do some people drink sweetened sodas between meals, rather than plain water? Is it because sodas quench thirst better than water? Is it because people are hungry and need the extra calories? If so, why not just eat a plain potato or a handful of unsalted nuts? The main reason people drink soda is that they enjoy it, plain and simple. They like the sweetness, they like the flavor, they like the feeling of carbonation on the tongue and the mild stimulation the caffeine provides. It’s the same reason people eat a thick slice of double chocolate cake even though they’re stuffed after a large meal. The reward system motivates you to seek the soda and cake, and the hedonic (pleasure) system encourages you to keep consuming it once you’ve begun.

But is this the same as addiction? If I took a person’s cola away, would they get the shakes? Would they break into a convenience store at night to get a cola fix? I’m going to say no.

I agree with Ziauddeen and colleagues that the evidence at this point is not sufficient to say that common obesity represents food addiction, and I appreciate their skeptical perspective on the matter. In obesity, as in leanness, the food reward system appears to be doing exactly what it evolved to do: seek out energy-dense, tasty food, and strongly suggest that you eat it. The problem is that we’re increasingly surrounded by easily accessible, cheap, commercial food that is designed to hit these circuits as hard as possible, with the goal of driving repeat purchase and consumption behaviors. Our brains are not malfunctioning; they’re reacting just as they’re supposed to around foods like this.

We need to talk about red meat ...

Last week, you probably heard about a study purporting to show that consuming any amount of red meat significantly upped your risk of premature death. If that news has you freaked out, I highly recommend reading Deborah Blum's roundup of high-quality news coverage of this study. Her piece explains what the study does say, what it doesn't say, and why some evidence is better than other evidence. The takeaway: You should probably be reducing the amount of processed meat that you eat (but we already knew that).

Triticum Fever, by Dr. William Davis, author of Wheat Belly

Quick: Name a common food, consumed every day by most people, that:

• Increases overall calorie consumption by 400 calories per day
• Affects the human brain in much the same way as morphine
• Has a greater impact on blood sugar levels than a candy bar
• Is consumed at the rate of 133 pounds per person per year
• Has been associated with increased Type 1 Diabetes
• Increases both insulin resistance and leptin resistance, conditions that lead to obesity
• Is the only common food with its own mortality rate

If you guessed sugar or high-fructose corn syrup, you're on the right track, but, no, that's not the correct answer.

The true culprit: Triticum aestivum, or modern wheat.

Note that I said "modern" wheat, because I would argue that what we are being sold today in the form of whole grain bread, raisin bagels, blueberry muffins, pizza, ciabatta, bruschetta, and so on is not the same grain our grandparents grew up on. It's not even close.

Modern wheat is the altered offspring of thousands of genetic manipulations, crude and sometimes bizarre techniques that pre-date the age of genetic modification. The result: a high-yield, 2-foot tall "semi-dwarf" plant that no more resembles the wheat consumed by our ancestors than a chimpanzee (which shares 99% of the same genes that we do) resembles a human. I trust that you can tell the difference that 1% makes.

The obvious outward differences are accompanied by biochemical differences. The gluten proteins in modern wheat, for instance, differ from the gluten proteins found in wheat as recently as 1960. This likely explains why the incidence of celiac disease, the devastating intestinal condition caused by gluten, has quadrupled in the past 40 years. Furthermore, a whole range of inflammatory diseases, from rheumatoid arthritis to inflammatory bowel disease, are also on the rise. Humans haven't changed -- but the wheat we consume has changed considerably.

Wheat Bellies

201110261359You've heard of "beer bellies," the protuberant, sagging abdomen of someone who drinks beer to excess. That distinctive look is often attributed to alcohol consumption when in fact it's just as likely to be caused by the pretzels -- not just the beer -- you're downing after work. A wheat belly is a protuberant, sagging abdomen that develops when you overindulge in wheat products like crackers, breads, waffles, pancakes, breakfast cereals and pasta. Dimpled or smooth, hairy or hairless, tense or flaccid, wheat bellies come in as many shapes, colors, and sizes as there are humans. But millions of Americans have a wheat belly, and the underlying metabolic reasons for having one are all the same.

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