Fatty Foods Affect Memory and Exercise | Hacker News Reader

Fatty Foods Affect Memory and Exercise

well.blogs.nytimes.com

12 pointshedgehog16 comments

I can't get at the full text without paying $7, which is not quite something I'm willing to do, but I'd question the timeframe of the experiment. Low-carb dieters frequently report that the first two or three days of the diet are very rough days due to low-energy, but then they bounce back and feel much better, often reporting that they feel better than before. (Self-reporting caveat here, of course. Note that I have heard real people say this in real life, though, not just diet books making the claim, though of course placebo may be in play.) My point here is not that the self-reports should be "trusted", for some value of "trusted", but that there's already anecdotal experience that indicates that the timeframe matters, which I would consider enough experience that investigation across more than just the "short term" is fully warranted. I read the abstract carefully and all it says for the time-frame is "short-term".

In terms of trying to help me understand my diet choices scientifically, this isn't any help, as it doesn't bring any new information in (and then, if I am correct about the timeframe, over-interprets the results). Short-term effects aren't the same as long-term effects in a self-correcting system like a living body.

If someone else is willing to drop the funds, let me know if they're more specific on the timeframe involved.

Here's a great response to the study from one of the icons of the Primal/Paleo/low-carb community:

http://www.marksdailyapple.com/high-fat-diets-make-us-stupid...

Executive summary: This study (or at least the media's response to it) attempts to extrapolate a 9-day study on rats to an overall implication on human diets.

>attempts to extrapolate

and fails

I got the full text. Sometimes NYTimes does that when you've viewed too many articles in a day. Just open up in a different browser or different computer. You can do it under the same IP. Clearing your cookies might do it, but i've only tried a different computer.

Not the NYTimes text, the text of the paper. I did read the NYTimes text, as well as the abstract of the paper.

This article - and the abstract - are not specific enough. What kind of fat is being used in the study? Does variety of fats make a difference? Do fats in combination with other foods change the outcome?

My own suspicion is that all of those factors matter, and making blanket statements on the basis of this one case is simply bad science.

It was tested on rats, so the type of fat probably doesn't matter (in regards to the effect on rats), since rats are more capable of handling and neutralizing the effects of bad fats than humans are.

EDIT (quoted from the comments by the author) "AND MORE INFO FROM DR. MURRAY:

This particular study didn’t look at any specific fat types, but used a fairly normal mix of saturated, polyunsaturated and monounsaturated fats, as well as long chain and medium chain fatty acids. The readers are absolutely right that not all are likely to be equal, so we are carrying out further studies to flush out the real culprits. My own feeling is that the long chain fats are the worst offenders when it comes to decreasing metabolic efficiency, with medium chain fatty acids (such as those in coconut oil) possibly being less detrimental."

well it can't be omega 3 right? cause Omega-3 supposedly helps ADHD sufferers with short term memory problems.

This could just as easily be the effect of fats on the sense of smell (smelling the condensed milk, not the corridor).

Or maybe it just wasn't as hungry, and thus less motivated. Fat is well known for giving a feeling of satiation.

Human studies showed similar results right?

As far as quantity of media coverage goes, this is the best one so far. So, no, not that I've heard of.

>maybe it just wasn't as hungry, and thus less motivated.

Jerome Klapka Jerome: "People who have tried it, tell me that a clear conscience makes you very happy and contented; but a full stomach does the business quite as well, and is cheaper, and more easily obtained."

So wait, you stress half the rats by changing their diet suddenly, and the other half you leave alone, and the stressed half under-performs, and you're surprised?

This study is not surprising in the least.

Brain burns glucose (on a "traditional" diet). On this high-fat diet (assuming that carbohydrates are dropped, and proteins are elevated), glucose is less available and different fats become more abundant, so the brain starts to use the fats as a fuel source (ketosis) instead of the glucose. This transition becomes easier and more efficient when there are very few carbohydrates in the diet.

Muscle fibers use glycogen (kinda the precursor to glucose) as an energy source, so when your body doesn't have any glucose to convert into glycogen... your body doesn't perform as well as it normally would.

Fun fact: A ketosis-based lifestyle is used by some body builders to lose body fat rapidly and by people with epilepsy to help control seizures.

It's worth noting that your explanations are also conjecture based on limited research data.

There actually aren't answers that are this clear about how our bodies use different types of foods, but human brains are wired up to place more trust in very precise explanations and answers. Your explanations are very precise, and thus, we tend to want to believe them.

This explains the popularity of several fad diets based on the model you describe. These diets may or may not be healthy ways to eat for prolonged periods of time. We don't know, because there are several different theoretical models for how the body processes food, and all of them are based on various, but nearly always, limited (in time span and in sample size) experimental data.

Where's kingkongrevenge when you need him?

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