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Medicine Science

Fatty Foods Affect Memory and Exercise Performance 379

Death Metal writes "Eating fatty food appears to take an almost immediate toll on both short-term memory and exercise performance, according to new research on rats and people. Other studies have suggested that that long-term consumption of a high-fat diet is associated with weight gain, heart disease and declines in cognitive function. But the new research shows how indulging in fatty foods over the course of a few days can affect the brain and body long before the extra pounds show up."
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Fatty Foods Affect Memory and Exercise Performance

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  • by Swizec ( 978239 ) on Monday August 17, 2009 @05:47AM (#29089507) Homepage
    Anecdotal evidence everyone is probably familiar with seems to confirm this. When you're at the office all day and decide to eat a pizza for lunch it seems very obvious that you're at least half way out of commission for the rest of the day. I had always assumed it was simply because one gets so stuffed from pizza, but apparently the high fat content played a big role too.

    Needless to say, I'm sticking to my low-fat diet with even more fervor henceforth ... although an occasional blunder feels SO good! Not while working though, this study clearly showed that.
  • Captain Obvious (Score:2, Insightful)

    by bmgoau ( 801508 ) on Monday August 17, 2009 @05:53AM (#29089545) Homepage

    Eating unhealthy foods causes health problems. News at 11. Try the new octo cheese burger while you're waiting.

  • Grace period (Score:5, Insightful)

    by illm ( 1106673 ) on Monday August 17, 2009 @06:04AM (#29089589)

    Switching your intake to a low-carb-high-fat diet involves a grace period a week or so. This is to allow the body to "reshape" itself to use the fat as an energy source instead of the previous intake of carbonhydrates.

    Symptoms of switching away from carbs to fat include; fatigue, dizzyness, high irritability and headache.

    "After only a few days on the high-fat diet, the rats performed 30 percent worse on the treadmill. After five days of testing, the treadmill performance of the rats eating fatty foods had declined by half."

    Any bells? So, nothing previously unknown to the lowcarbers here.

    Personally, I tried the lowcarb-highfat diet about half a year ago, and actually did lose a few kilos, but the most interesting change for me was that I felt more awake, my stomach stopped producing funny amounts of gas, and never ever felt hungry. I got tired of it after a while though - I kinda missed the occasional potato and pasta - so I've taken back the lost kilos again. These days I just don't shun fat and avoid sugary stuff. Both me and my previously upset stomach feels great now.

  • by romeanthem2 ( 1220126 ) on Monday August 17, 2009 @06:08AM (#29089603)
    More fat is bad rubbish. I am supposed to believe that eating saturated fat is bad but of course eating lots of carbs is good. Of course the first thing the body does to excess carbs is to convert them to saturated fat in the liver. Why not just eat fat directly and give the liver a break, whilst maintaining my insulin sensitivity? If any one still believes the lipid hypothesis I suggest you log onto Hyperlipid and spend some time reading.
  • by Ed Avis ( 5917 ) <> on Monday August 17, 2009 @06:16AM (#29089651) Homepage
    From the article:

    To determine the effect of a fatty diet on memory and muscle performance, researchers studied 32 rats that were fed low-fat rat chow and trained for two months to complete a challenging maze.

    And then later, some of the rats had their diet changed to a high-fat diet and others kept the same diet as before. But perhaps they just performed worse because the diet differed from what they were used to? To make a fair experiment there should also be a group of rats who were fed on a high-fat diet for two months during training, and then switched to low-fat for tests. Perhaps their performance would worsen too.

  • by JasterBobaMereel ( 1102861 ) on Monday August 17, 2009 @07:30AM (#29089939)

    If your body takes in more fat/protein/carbs etc than it needs it will either excrete them or store them... which it does depends partly on your genetic makeup, but more so on your recent pattern of diet/exercise

    If you have a healthy balanced diet and do adequate exercise (not very much, and could be normal activity) then occasionally eating unhealthy foods will do no long term harm, your body will not need the extra, and does not think it needs to store it so will simply excrete the excess ....

    If you starve yourself of food, or one type of nutrient then when you eat it your body will store any excess, because it thinks times are hard, this is why proper nutritionalists do not recommend mono diets (like Atkins) and when they do advise short term unbalanced diets, then they make sure you come off them slowly so this reaction does not occur ...

    Atkins has been proved to work for two reasons, you are on a diet and are having to watch what you eat and you tend to order ordinary meals and then not eat part of it ... so you eat less, and it is high protein so you are getting enough energy so you feel full no snacking, but as a long term diet it is unhealthy and when you stop you can't just go back to a unheathly diet ....

  • by value_added ( 719364 ) on Monday August 17, 2009 @07:50AM (#29089999)

    I Cut every carb, coke, icecream, sugar, bread, rice, pasta, cookies, chips even water mellon. And begin to eat meat etc.

    It's worth pointing out that doing so means your grocery bill will tend to go up. Not a bad thing, of course, but in a world where people demand things being cheap (i.e., subsidised, or the product of industrial farming techniques), it may be difficult for the average person to see the value in doing so. Chickens, for example, were once upon a time considered "special" and eaten at most once per week. Today, we expect them at the drive-thru window.

    Moreover, in tough economic times, the average person will want to lower the amount of money they spend, not increase it for "non-essentials" like healthy food. Poor people doubly so. From least to most expensive, our buying choices could be crudely summarised as:

    1. Dirt
    2. Refined Sugar or Corn Syrup
    3. Carbohydrates
    4. Protein
    5. Fruits and Vegetables
    6. Fats (Olive Oil, Butter, etc.)
    7. Nuts
    8. Champaign, Caviar or Hookers

    So replace protein with carbohydrates if you can. I have lots of wealthy friends who do just that and demand fresh fish (fresh grilled salmon seems the most popular choice) on a daily basis. Those same people are quick to offer up factoids such as "Walnuts are a perfect food" without worrying that they cost more per pound than expensive cuts of meat. By contrast, the poor people I know typically limit their choices to refined sugar and carbohydrates.

    Granted, protein is available from different sources (beans, dairy, meat from various animals) at different costs, but most of will always prefer the meat variety to form the basis of our diet.

    As for the conclusions of the article, I'd raise the question that if you've succeeded in getting a happy dose of fat into your system at one indulgent sitting, what need or motivation is there for cognitive thinking? It may be that your body is telling you to just enjoy the feeling and do nothing else. Put another way, eating a pint of ice cream is not unlike smoking a joint; it's supposed to be its own reward. If you expected to be doing something else (like drive, work, operate heavy machinery, or do math), then maybe you made the wrong choice. ;-)

  • Re:Captain Obvious (Score:5, Insightful)

    by radtea ( 464814 ) on Monday August 17, 2009 @08:45AM (#29090247)

    Eating unhealthy foods causes health problems

    The study is actually very poorly designed and proves nothing of the kind. Your comment is an example of confirmation bias, as are the researcher's conclusions.

    A well-designed study would start half the rats on the high-fat diet, the other half on the low fat diet. Train them to run the mazes, then switch the diets.

    It may well be that the effect being observed here is "massive sudden dietary change reduces cognitive performance."

    If you consider how uncomfortable and distracted you'd probably be if you were subject to this kind of violent dietary manipulation you'll see how plausible the alternative explanation is.

    I share your biases with regard to fatty foods, but that doesn't mean I can't tell a poorly designed study when I see one.

  • by Fished ( 574624 ) <> on Monday August 17, 2009 @08:46AM (#29090257)
    Why do you assume it's the fat in the pizza and not the carbohydrate? Relatively speaking, Pizza is at least as high in carbohydrate as it is in fat, if not quite a bit higher.
  • by dunkelfalke ( 91624 ) on Monday August 17, 2009 @09:05AM (#29090441)

    Yes, sure, but please show me the great Inuit civilization. Oh, there is none?

    All great civilizations had one in common: the use of agriculture.

  • by Type44Q ( 1233630 ) on Monday August 17, 2009 @09:06AM (#29090451)
    I believe your observations are accurate and your suspicions [that the type of fat is what matters] are entirely correct.

    In the 80's, the 'health food' movement was, for the most part, focused on 'low fat' diets. We've since learned that not all fats are created equal; some (your almonds for example) are incredibly beneficial to the body, actually among the most nutritious things you can consume (some other foods that come to mind are avacados and flax seeds, which are incredible healthy [i]because[/i] of their fat).

    Obviously in addition to fats we also need proteins, vitamins, minerals... but what we DON'T need are the grains (in general; refined flour in particular), dairy and low-grade cooking oils (I'm going to leave the whole vegetarian thing for another day)... and you've experienced first hand what inundating your system with that shit will do to you. The fact of the matter is that we humans just began eating grains and dairy products yesterday, in evolutionary terms, and our bodies don't have a fucking clue what to do with them (there's evidence that letting some of these products be fermented by beneficial bacteria - yogurt, tempeh in the case of soy - allows our systems to process them better).

    I've developed a simple method for determining whether or not I think something might be appropriate for me (i.e. let me feel and perform my best): I try to picture a chimp or gorilla chowing down on it in the wild; if I can't, I assume it's probably not the best thing for me to eat. As for whether or not my willpower allows me to avoid eating it... that tends to vary. ;)

  • by Anonymous Coward on Monday August 17, 2009 @09:07AM (#29090479)

    I'm always amused when people who think they know better make fools of themselves.

    There are plenty of carbs that humans can digest without cooking -- fruit, nuts, vegetables. Not all grains have to be ground down into a power, either -- ever heard of the term "whole grain"? And what is wrong with the need to cook a food before you can eat it -- how does that automatically make it "bad"?

    If your diet works for you, that's good. But please don't spread bullshit.

  • by hey! ( 33014 ) on Monday August 17, 2009 @09:13AM (#29090549) Homepage Journal

    That's a good point. More than once, early research and nutritional advice on "fats" has been shaded by later research which distinguishes between kinds of fats. The heart dangers of "fat" turned out to be for saturated fats. Then we decided that trans fats, which are unsaturated, are even worse. Then we decided that conjugated linoleic acid, is good, and that's a trans fat.

    I suspect that fats are the one nutrient where the "organic" movement got it right. Foods naturally high in fat are probably better than foods manipulated to increase their fat content. Free range beef is not only leaner than feedlot beef, it has more of the omega 3 fatty acids that we associate with fish; fats that seem to have heart, blood pressure and possibly cognitive benefits. Fats are as different from each other as a poodle from a pit bull.

    So the research, while important, isn't enough to make any kind of dietary adjustments that haven't been warranted by prior research. It seems almost certain that if it can be replicated, it will not be replicated with all kinds of fats.

    Additionally, I see a flaw in the methodology -- as reported of course. We can't trust the media to get it right. The researcher was performed on rats who were rewarded by food for performing tasks. Unless the researchers controlled for the greater satiety value of fat, you'd expect the fat fed rats to perform less well. You could get the same results by testing rats who had just eaten versus ones that had been fasting for a short time.

  • by jpstanle ( 1604059 ) on Monday August 17, 2009 @09:27AM (#29090709)
    Among all the other flaws with this study, I'm surprised nobody else has pointed out that this study was performed with rats who have a vastly different diet than humans. Freshly hunted meat certainly is not a primary portion of a rat's diet, whereas historically speaking, it is for humans.
  • by Guse ( 1283076 ) on Monday August 17, 2009 @09:54AM (#29091119)
    1) It's unfortunate that you had to stoop to an ad hominem attack in an otherwise decent rebuttal. It really is.

    2) You're basically wrong on virtually every account. There *is* ample evidence that low-carb diets are bad for your brain [], heart [] and kidneys [].

    3) The Inuits lack of farming couldn't have much to do with the fact that they lived in the freakin Arctic Circle [], could it?

    "Again, there is ample evidence to show that some people (as in many thousands) have consumed well under 2000 calories a month for decades, in the form of carbohydrates, while doing hard physical work - and wound up grossly obese. Just as others (usually much wealthier) have eaten far more than 2000 calories a day for years, while doing little or no physical work, and remained lean and fit."

    Really? Under 2000 calories a day and hard work and gotten obese? Please provide this ample evidence.

    My theory, developed after I lost 60 lbs, was that whenever you have two things that are diametrically opposed like low-fat, high carb/low-carb, high fat is that the answer is most frequently in the middle. Moderation in both (including carbs, a necessary source of energy) leads to great results. But, that's just my anecdotal evidence talking.

  • a high carb diet (Score:4, Insightful)

    by circletimessquare ( 444983 ) <> on Monday August 17, 2009 @10:37AM (#29091705) Homepage Journal

    is like punching your pancreas: it spikes sugars in the blood, abusing your insulin making mechanisms

    a high protein diet

    can destroy your kidneys, put you in ketoacidosis, etc., etc., and other such nonsense scare tactics

    did you know water can KILL you!?

    look: eat carbs: complex unprocessed grains, so your blood sugars rise and fall slowly

    eat protein: good sources like fish and egg that have biotin and omega-3s for brain health

    and eat fat: good fats like olive oil. you actually want fats in your bloodstream, that's what hdl is. ldl deposits plauqes, hdl sweeps them up

    so what do you do about the food you eat? you eat wholesome complex little processed foods, you eat them in moderation, and you get exercise

    that's it, that's the magic

    for those of you slurping down mountain dew at 3 am and eating bacon cheeseburgers all day: you're taking years off your life. which might be fine with you. in which case, when you read articles like this, toast a cheer your devil-may-care lack of interest in taking care of yourself, and congratualtions on less women being interested in you and your health problems in your 30s and 40s

    life is short, take care of your body. it hardly means much now, but you will hate yourself in your 60s if you treat your body so badly. or, you could feel like you are in your 30s when you are in your 60s. its up to you. no pain (temporary, addiction like withdrawal from unhealthy foods now), no gain (a longer, richer life)

  • by scorp1us ( 235526 ) on Monday August 17, 2009 @11:52AM (#29092895) Journal
    You are too dependent on your stomach to supply your blood sugar. I had this same problem in my 20s. While it is scary to be shaking if you wait a few hours you'll be fine. However it is no way to live going to meal to meal and just barely making it before the shakes set in.

    Insulin stores excess blood sugar to fat so you don't going into a coma. Glucagon is the opposite, taking fat and putting it in the blood stream as sugar. Insulin work on short (15 minute) time scales. Gucagon work on hour/day time scales. It takes 3 days of no carbs to bring your glucagon levels up to the point of fully being able to provide al the blood sugar you need. Both glucagon and insulin have an inverse relationship. If your insulin is high, then glucagon is shut off. (You don't want it constantly providing blood sugar when you are about to go into a coma.

    So what is happening in your body is called hyperinsulinism. You eat something, feel better, you burn some store the rest. Then your blood sugar drops below cellular satiation level. You feel hungry and get the shakes. You reach for more food as the cure... The same thing happens with rats. Take a rat, put it in a cage and provide it two sweetened water sources, one sugar, and the other a synthetic 0 calorie sweetener. At the start of the experiment, it will drink from both equally. But of the course of a few days it will only be drinking from the sugar one. Insulin makes you dependent on insulin because of its fast acting nature compared to glucagon.

    I broke the cycle by not eating simple carbs. No sugary drinks, and no breads. Complex carbs like beans are ok. Basically a low-glycemic index diet is what all adults should be on. One benefit of this is with my near-zero carb diet, I can go an entire day without eating an not be hungry or tired. My glucagon level stays elevated and I am in a constant fat-burning mode. If I get hungry it is only because I ate carbs about 4 hours before. (I do allow one day a week to let loose and have cake. It seems that at zero carbs all the time I'd get dizzy and sick whenever I ate them because the rush of blood sugar was too much. I lost my lunch a couple times that way) If you are hungry, the best thing to eat is something that will slowly digest with lasting energy. Proteins are great but won't fix your immediate hunger. The trick I do is this: liquid carbs - like a Vitamin Water 10 (25 cals/bottle) fast acting, then eat something at the same time to provide a longer-duration energy source.

    I cannot recommend a low-carb diet enough. It is so liberating. The Aborigines have a saying along the lines of "Western man looks at his watch to see when to eat" which highlights the differences between our diets. We are constantly looking for our next meal because of the carb/insulin dependence caused by our diets. They don't share the diet or the addiction. FYI: A person with a modest 10% body fat can live for a whopping 30 days on those reserves. What you experience in hunger intensity is not proportional to your survival predicament.

    FYI: the "Atkins" diet was known to work in the 1800s, when it was called the "Banting diet" after Charles Banting whose physician recommended it. It worked so well he went about sharing it with the world.

    I highly recommend everyone read "Good Calories Bad Calories" by Taubes, which is a fantastic book that critically examines what the mainstream media claims about diet.
  • by Tenebrousedge ( 1226584 ) <(moc.liamg) (ta) (egdesuorbenet)> on Monday August 17, 2009 @12:03PM (#29093105)

    I will not dignify that remark by asking for a citation.

    Why was it that European civilizations took over large parts of the world, and not e.g. the Chinese or Indian peoples?

    'Advanced' civilizations are far more dependent on horses, iron, livestock, and certain grains than innate intelligence. You can't think up iron deposits no matter how much rice you've been eating.

    How did European settlers displace the Native Americans? With pigs, cows, sheep, barley, wheat, steel, and the diseases that come from living with livestock. They did not introduce agriculture to the Americas, nor did they outthink the native populations. They simply had a better set of native species to work with.

    Please read Guns, Germs, and Steel, to obtain a general overview of the subject at hand. If you must justify your latent racism somehow, then I imagine any criticism of that work would provide you with a base for further argument.

  • by sjames ( 1099 ) on Monday August 17, 2009 @11:01PM (#29100623) Homepage Journal

    Funny thing thermodynamics. It always works but only if you do a sufficiently complete analysis.

    I used to have a car that could go 10 miles on the energy in 1 gallon of gas. My current car goes 30 miles on that same amount of energy. It goes a bit less if I run the A/C (back when that worked).

    Energy in == energy out except that that energy out can be heat from resting metabolism, more or less heat generated for the same amount of exercise, energy going right through and coming out in waste or consumed by bacteria in the gut (more heat, more energy in waste), and on and on.

    The sleight of hand is in the implicit (and incorrect) equation of energy out == exercise.

    A prominent example is protein starvation (AKA rabbit starvation). The human body can only convert about 1600 Kcal/day worth of protein. The rest is wasted. You can go on a strict protein only diet of 10,000 Kcal a day and lose weight, but you'll feel quite sick doing so.

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