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Matching DNA To a Diet Doesn't Work (statnews.com)

DNA testing won't guide dieters to the weight-loss regimen most likely to work for them, scientists reported on Tuesday. From a report: Despite some earlier studies claiming that genetic variants predict whether someone has a better chance of shedding pounds on a low-carbohydrate or a low-fat diet, and despite a growing industry premised on that notion, the most rigorous study so far found no difference in weight loss between overweight people on diets that "matched" their genotype and those on diets that didn't. The findings make it less likely that genetics might explain why only some people manage to lose weight on a low-carb diet like Atkins and why others succeed with a low-fat one (even though the vast majority of dieters don't keep off whatever pounds they lose). Unlike cancer treatments, diets can't be matched to genotype, the new study shows. The results underline "how, for most people, knowing genetic risk information doesn't have a big impact," said Timothy Caulfield, of the University of Alberta, a critic of quackery.

14 of 70 comments (clear)

  1. gut biome? by supernova87a · · Score: 4, Interesting

    I wonder whether it can be explained by the gut biome taking a large role in the actual metabolism of food consumed? There's all the stories lately about how the composition and behavior of the gut bacteria actually favor/prevent people's efforts to change their diet and effects on weight. Would make sense then that one's own DNA has less to do with it.

    1. Re:gut biome? by magzteel · · Score: 4, Interesting

      I wonder whether it can be explained by the gut biome taking a large role in the actual metabolism of food consumed? There's all the stories lately about how the composition and behavior of the gut bacteria actually favor/prevent people's efforts to change their diet and effects on weight. Would make sense then that one's own DNA has less to do with it.

      I think the gut bacteria studies look very promising. The impact of fecal transplant from an obese person to a thin person has been observed multiple times.

      The DNA thing is old news. This is from 2006. I've read much older articles too. All say it is quackery.
      http://www.nbcnews.com/id/1406...

    2. Re:gut biome? by king+neckbeard · · Score: 2

      I think you are on the right path. Matching DNA to diet probably does work. The problem is the idiots running the study were trying to match diet to the DNA of the meatsack instead of the DNA of the biome.

      --
      This is my signature. There are many like it, but this one is mine.
    3. Re:gut biome? by Anonymous Coward · · Score: 2, Funny

      The easiest weight loss is this: place less force on the scale when you are fully supported by it. I lost over 30 lbs by simply ensuring that when I was stepping on the scale, I exerted less force than I did in the past.

      Of course, later I put more force on the scale. It is harder to continue putting less force on the scale when you have more mass.

    4. Re:gut biome? by ShanghaiBill · · Score: 4, Insightful

      Easiest diet is this: expend more than you take in.

      That is the easiest to understand, not the easiest to do.

      I fell off the diet while in grad school and gained it back and more.

      If it was so easy, why did you fail?

    5. Re:gut biome? by ShanghaiBill · · Score: 2

      The diet succeeded.

      If temporary weight loss counts as a "success", then here is an even simpler "diet": Go sit in a sauna for an hour.

      Losing weight is easy. Keeping it off is hard. Sure, you found a novel formula for weight loss that nobody ever thought of before (i.e.: eating less), but that only helps with the easy part.

    6. Re:gut biome? by Kjella · · Score: 5, Informative

      Easiest diet is this: expend more than you take in. I lost 30lbs over 3 months my senior year of college eating mostly 2 things that most diets tell you to stay away from: meat and rice. But I kept what I consumed to a minimum and worked out regularly.

      Everybody can lose weight working out. But I've found that to exercise enough to offset a constant calorie surplus is almost impossible unless you're an athlete or something. When I was fairly fit I could burn 1000 calories in a 1.5 hour workout. One Big Mac with medium fries and non-diet Coke and it's all a waste (997 kcal says the calculator here in Norway). One 0.5 liter beer = 200 kcal, 100 grams of potato chips = 500 kcal so binge at one party and spend forever paying it off. Sure you don't do that every day but you probably don't work out every day either.

      Realistically I'd do maybe do 2-3 workouts of 6-700 kcal a week so 1500/week average. It's still a rounding error compared to the 2500*7 = 17500 kcal they calculate for a regular diet. It's not even 10%. And you need room in the budget for some luxuries too or the boredom will kill you, which means that most days you need a light deficit. That said, I have a pretty clear minimum threshold before hunger drives me crazy. If I want to lose more than that, I need to exercise. And there's other reasons to exercise too, fat to muscle ratio for one. And muscle is far more compact, you look better.

      I found losing weight to be relatively easy, it's a "project" where you eat healthy and exercise with no stupid calories. Sustaining a weight though, in a lifestyle you can imagine doing for years that's the hard part. I'd exhaust my motivation, snap and gain back a lot of weight pretty quickly. Same with exercise - I once ran a half marathon on too thin a foundation, threw my running shoes in the closet and found them six months later with the tag still attached. So I've worked a lot on how I can trim the corners without feeling like I'm dieting. Because even 300 g/week is 15 kg in a year, if you can't keep it steady there's no point.

      I think my biggest victory is that I've found the willpower to wait for the "second hunger", you know how you get tired, overtired, then *really* tired? I've found it's the same for hunger, if you make it past that first "hey, you got some snack for me I could store as fat for the winter" hunger the body will kinda shut up about it for a while until the warning lights come on to say "hey, this body could really use some energy right now because we're running on fumes". I guess it's the old hunter-gatherer instincts kicking in, no reason for your body to wail about food if there's none to be had right now. They didn't have well stocked fridges 24x7x365.

      --
      Live today, because you never know what tomorrow brings
  2. The only diet that works... by Oswald+McWeany · · Score: 5, Insightful

    The only diet that works is one that you are happy sticking with. Sure, it's easy to lose a bunch of weight. I've lost 30lbs+ three times. That weight comes back if it's "a diet." The only diet that works though is the one that ceases to be a diet and becomes the lifestyle.

    If you hate your diet- you're never going to stick on it. If you're happier leaving out carbs- leave out carbs. If you're happier counting calories- count calories. If you want to cut fat, cut fat.

    Overall though, if this isn't something you can do for the rest of your life, the weight will come back. Everyone needs to find the diet that they are happy with. That's the only way they can reach their ideal weight. You can never stop being on "a diet" so it has to be something you love.

    --
    "That's the way to do it" - Punch
    1. Re:The only diet that works... by fedos · · Score: 3, Funny

      Allow me to present you this trophy for championship-level Missing the Point.

  3. Viome by goombah99 · · Score: 3, Informative

    Check out the company Viome. They do exactly that. Matching biome to diet

    --
    Some drink at the fountain of knowledge. Others just gargle.
  4. No surprise by Quirkz · · Score: 4, Insightful

    Diet and nutrition appear to be incredibly complex. For very good evolutionary reasons, it seems to be a flexible, creative system, with a lot of redundancies, failovers, and alternatives. The more I learn, the more I realize just how laughably little we know. It doesn't help that the field is filled with quackery, moralizing, conspiracy theories, and so, so many people determined to shore up a presupposed agenda, as opposed to searching for the truth. Also, the amount of money on the table just encourages the craziness.

    I think eventually we will find things that are DNA-dependent, but many of those will be niche. A heart medicine comes to mind, which in trials did almost nothing for the general populace, but was found to work wonders for men of African descent. There are also a lot of other known issues dealing with medical effectiveness and dosing based on people's biological ability to use or remove the drug from their systems.

    But I suspect for a lot of issues, most of the time results will be pretty general. Bodies that can burn both fat and sugar for energy might not have a reason to lose weight if the calorie intake is the same, but the scales are tipped in favor of either fat or sugar. Or we may find that certain genetic types respond well to a particular diet, but only if two or three other related factors are also strictly controlled for.

    It sure as hell isn't going to hinge on something as simple as your blood type; that I know for sure.

  5. Low Carb by Zorro · · Score: 4, Insightful

    Seems the rise in weight and diseases really kicked off with the Fat Free fad.

    The fat was replaced with carbohydrates.

    And it has just been going up ever since.

    Read what is in your food and you will notice the western diet consumes massive amounts of carbohydrates.

  6. Pigs by pubwvj · · Score: 4, Interesting

    I raise pigs.

    I raise a lot of pigs.

    I raise thousands of pigs out on pasture.

    I am deep into the genetics of my pigs, that is to say I do very hard selective breeding between my nine lines of genetics in order to produce the best pigs for our market niche that will thrive in the outdoors (we pasture pigs) in our climate (USDA Zone 3 northern Vermont mountains) on our pig diet (80%DMI pasture, 7%DMI dairy (primarily whey), 2%DMI spent barley from a local brew pub, 1%DMI eggs from our pastured hens, 1% dated bread (great treat for pigs) plus apples, pears, sunflowers and other things we grow.)

    Genetics make a HUGE difference in the pigs. Pigs with poor genetics do not perform as well - all on the same diet. I have selectively bred for pigs that thrive on our climate, diet and management. Looking over my decades of selective breeding of our herds I can clearly see the improvement in the animals and it is genetic, not environment.

    Gut biome also makes a difference - yogurt helps, piglets eating their mother's manure helps to inoculate their guts with the right bacteria.

    What I've done in pigs I suspect also applies very strongly to humans. Of course, with the pigs I'm aiming to put on weight while with humans we're looking to not put on (too much) weight. But actually you see it is closer than you might think because I do not want fat pigs. I want good muscling with marbling and about 2 cm to 3 cm of fat cap on the back.

    So for a human lets use me as an example. I eat a high meat, high cholesterol and high fat diet. I eat a lot more than the daily recommended calories - but then I'm not an office worker sitting on my butt. But here's the interesting part, I have excellent blood chemistry even with that diet. Today I happen to be at the doctor's office for my annual physical today and got my blood labs done. The doctor was very pleased. He said keep doing what ever it is I do because it works.

    What do I do, besides eating meat for two to three meals a day, seven days a week? Well, I get a lot of varied exercise every day. I farm. I do construction. I live on the side of a mountain. I built and operate my own on-farm USDA/State inspectable butcher shop. That means most days are moderate exercise for me - what most people would consider pretty heavy exercise for six to ten hours a day. Two to three days a week we do nine to ten hours a day of very heavy exercise - marathon butchery sessions. I figure I lift about 16,000 to 35,000 lbs in reps of 1 to 200 lbs each those days.

    My sons and daughter are like me and so is their mother although she carries a little bit of extra weight - probably it is from not getting as much exercise.

    We eat carbohydrates and sugars in moderation. A little ice cream or cake once in a while. A little bread once in a while. But neither is a big part of our diet.

    Mostly we drink mint tea, hot chocolate and milk. Not much in the way of sodas although occasional, maybe five or ten a year. Little to no alcohol other than in cooking. (Alcohol gives a lot of calories which is why I mention it here.)

    Genetics may be a partial factor: my father and one of my brothers, who looks like my father, have high cholesterol but are trim. My other siblings, my mother and I all have low cholesterol. My mother is over weight, the rest of us are not. I'm the most physically active of all of us and I'm the heaviest - high muscle and bone density, trim with narrow waist, no inch to pinch.

    This is a very small data set but it does suggest a genetic component.

    I suspect that the exercise is the key component - we burn a lot of calories - but my siblings are all trim and they don't get nearly as much exercise. My guess is that the other big issue is genetics, contrary to the headline on this article.

    So back to the original research, my guess is they just don't understand the genetic well enough yet to apply them to dietary recommendations. With more research and time that will come. After all, look at how well we understand animal diets and genetics.

  7. Re:Hackers Diet by Bengie · · Score: 2

    There was a recent study about cal in vs out and given the same food to the same demographic of people, there is an up-to 50% deviation. Someone may absorb 50% more and someone may absorb 50% less. They did this by placing the people in a small isolated room with IR cameras and other sensors, then measured energy entering and leaving the box in all of its forms, including analyzing the bio waste.