I've blogged several times on here about the connection between microbes and obesity (aka "infectobesity;" previous posts here, here, and here.). It's an interesting area of study, with two general directions: investigating which of our gut flora (alone or in combination with others) affect our metabolism; and how other types of infections (such as adenovirus serotype 36) can play a role in this process as well.
A recent story in the New York Times Magazine by Robin Marantz Henig provides a nice introduction to this whole area, weaving in the threads I mentioned above (as far as the science goes), and adding the extra angle of how obese patients are treated and why obesity researchers feel that it's critical to understand all of these interactions that lead to obesity: bringing in host genetics and microbial factors in addition to the common advice regarding diet and exercise. Some of the anecdotes are fascinating:
One of Atkinson's most memorable patients was Janet S., a bright, funny 25-year-old who weighed 348 pounds when she finally made her way to U.C.L.A. in 1975. In exchange for agreeing to be hospitalized for three months so scientists could study them, Janet and the other obese research subjects (30 in all) each received a free intestinal bypass. During the three months of presurgical study, the dietitian on the research team calculated how many calories it should take for a 5-foot-6-inch woman like Janet to maintain a weight of 348. They fed her exactly that many calories -- no more, no less. She dutifully ate what she was told, and she gained 12 pounds in two weeks -- almost a pound a day."I don't think I'd ever gained that much weight that quickly," recalled Janet, who asked me not to use her full name because she didn't want people to know how fat she had once been. The doctors accused her of sneaking snacks into the hospital. "But I told them, 'I'm gaining weight because you're feeding me a tremendous amount of food!' "
It's noted early in the article that many of the subjects did overeat--the average calorie intake was 6,700 calories a day. But as cases like Janet's show, calories in are only a part of the equation, and even people who eat relatively little may gain weight because of factors they're not easily able to control.
Later in the article, this is noted. Regarding the simple equation of "calories in < calories out = weight loss," Henig writes:
Current public-health messages deny this harsh reality. They make losing weight sound easy, just a simple matter of doing the math and applying some willpower. A pound of fat contains 3,500 calories, government documents say, and if you cut down a week's worth of food intake or increase exercise by a total of 3,500 calories, then, voilà -- you lose a pound. "To lose weight, you must use more energy than you take in," states the Web site of the Office of the Surgeon General. "A difference of one 12-oz. soda (150 calories) or 30 minutes of brisk walking most days can add or subtract approximately 10 pounds to your weight each year."
But if genes or viral infection or gut microflora are involved, then for some people 3,500 calories might not equal a pound of fat, and 150 fewer calories a day might not mean they'll lose 10 pounds in a year. As scientists continue to investigate how obese people are different, we can only hope that a side benefit will be a more largehearted understanding of what it means to be fat and how hard it is to try to become, and to remain, less fat.
Like most things in life, losing weight isn't as black and white as we may like it to be. But by searching for these additional factors that affect weight, it at least gives researchers and physicians more weapons with which to fight the growing problem (no pun intended).
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Tara, my doctor has me scheduled for obesity surgery as soon as my insurance will agree to the procedure (this is Cigna, so I have about five months to go). I'm exactly like the gal in your post, someone who eats a normal amount while being unable to lose weight (I'm a vegetarian and don't even LIKE sugary or greasy stuff). Frankly my doctor does not believe me when I say so and I'm starting to disbelieve myself.
Is any of this microbiological stuff ready to present to my doctor as a viable avenue for seeing what is wrong with my body? I'm not looking for excuses... I'm looking for answers. I'm terrified the surgery won't work.
Hi speedwell,
I can email you a few articles and reviews, if you like; just drop me a line. You could discuss them with your doctor, but at this point, there's really nothing they can do about it, even if they are affecting your weight. And either way, even if they are, they're only one component of it--diet and exercise still play a role. I assume your doctor is having you keep some kind of food journal? That's the first thing I did several years ago when I resolved to lose some of the post-baby weight. I found that even eating the regular ~2000 calories a day was way too much for me. Even when I'm working out regularly (~3x/week, vigorious cardio + weights), if I go above around 1200 calories a day, I start to gain. (When I'm not hitting the gym, I'd guess I could get by with much less than that--many people consume that amount of calories in a single meal!). At least having a record of what you eat can convince yourself (or point out areas where you may be adding calories and not realize it), even if it doesn't convince your doctor.
Hmm. Ok, fair enough. Thanks!
Here's another anecdotal story for all of you scientists and experts. And if you have an actual explanation for what happened, I'd appreciate it. ;)
I used to weigh over 370 pounds (that was as high as the gym scale went) and got down to 153 through extreme caloric restriction. Then I had first of all some reaction to something and got a bad case of edema. A Doctor is treating me for that with lasix and it's going down. That's weird but not the weirdest thing.
About 3 months ago I suddenly had *extreme* cravings for food. I literally stayed awake all night thinking about how I could sneak food while my wife was away the next day. There was just a little voice in my head that kept saying over and over that I could buy the food, hide it until she left for the day, and eat it all before she was back. That has never happened before. After about 3 months of just compulsive eating it's finally starting to go away but I've slipped back in to all of my bad habits and I've gained back 70+ pounds.
I don't know what the scientific explanation is for that episode I had, but I can tell you that there's at least some mental component as well.
After spending most of the first 42 years or so of my life at or near ideal weight, I suddenly found myself with so little energy that I'd wake up in the morning already planning when I could sleep next. Needless to say, I got very little exercise. At the same time, my appetite went WAY up. I put on 40 pounds in two years, half of it in only six months, and almost all of it from the larger helpings of meals that I needed to avoid being miserably ravenous all the time.
I finally got this under control when a few rounds of blood tests revealed a rather subtle endocrine dysfunction that was, fortunately, treatable. I've been able to get 20 of those extra pounds off and keep them off, but the remaining 20 will probably always be with me. I exercise regularly, minimize my consumption of greasy and sugary food, and try to control my portion sizes at meals. But I refuse to go on what most people think of as "diets". I really don't need to develop an eating disorder at my age.
The above experience, combined with my friendship with someone who went through successful bariatric surgery, has taught me to NEVER make assumptions about how obese people got that way. Yes, many of us do have or develop bad habits. But bad food is also heavily marketed in this culture, and many people, paradoxically, have jobs that are both physically exhausting and preclude getting real exercise. We're also just learning some things about variation in human metabolism, as the story of Janet S. illustrates.
Incidentally, during the time when I was gaining weight rapidly, I almost never snacked and rarely ate desserts. Today, I do snack occasionally, which actually seems to help me keep from overeating at meals.
In the meantime, the take-home message that I'd like to give to those who disdain overweight or obese people: Note that it can happen to you.
Thanks for blogging on that article in the NY Times Magazine. I passed it on to my nutritionist to see what she thinks of it. I've been working with her for several years to keep my weight in line, keeping a record of my eating and exercise the whole time. It's been a tough slog and while I've kept some of my extra weight off, there are still a lot of extra pounds.
The one point in the article which really caught my attention was Nikhil Dhurandhar's finding that those infected with the virus had unusually low cholesterol and triglyceride counts. That's been true for me as well. I've had doctors tell me they wish they had my numbers. It would be interesting if a virus was causing this.
I agree with your reading of the article - that nobody's advanced far enough with this research to have it be used in treating obesity.
The saddest part of the whole article was toward the end where she writes of the finding that obese people who've lost weight need 15 percent fewer calories to maintain a given weight than people who've never been obese. It's great if you're in a famine but otherwise it sucks.
Thanks SO much for posting this - there is gross institutional resistance to accepting that those caloric intake guidelines are just plain WRONG. I've known for years that if I eat what I'm supposed to eat to "maintain" my weight, I'll gain. However, no nutritionist would ever believe I ate less than that. Instead, they implied I was lying - just as with the patient in the article.
At this point, I've rejected "official" nutritional advice and created my own diet, which defies those calorie calculators (I'm operating on a huge caloric deficit each day - yay for caloric restriction!). I'm quite healthy, but I'm still mad about all the years I wasted being fat - and I worry about all the young people fighting obesity who are given inappropriate guidelines, then blamed for the failure of their diets. Until we realize there is no "one size fits all" nutritional equation, many will continue either giving up entirely, or succumbing to eating disorders.
Very interesting. But I doubt awareness of this will spread quickly. I've seen an endocrinologist be completely unaware of the underlying cause of a common endocrine disorder because it was discovered and usually only treated in the field of reproductive endocrinology. How much less likely is it that GPs will recognize that viruses can make people fat? (And how can they know which people are which other than admitting them or stalking them to monitor their food intake?)
Yeah, one thing we need is a good test--and then treatment--for Adv36. That requires clinical trials, though, and awareness, and someone to pick up the tab.
I am a nursing student currently taking Micro. This was a fascinating post as were your related three you refrenced. Thanks for sharing. I had no idea microbes could be such a ranking factor.
I am a nursing student currently taking Micro. This was a fascinating post as were your related three you refrenced. Thanks for sharing. I had no idea microbes could be such a ranking factor.