Flutterby™! : Low fat questionable 2006-02-08 16:39:52.783792+00

Low fat questionable

2006-02-08 16:39:52.783792+00 by Dan Lyke 8 comments

12 year study shows no effect from low fat diet on heart disease and stroke in women:

"People shouldn't be disappointed by the studies,'' said Marcia Stefanick, a Stanford University School of Medicine professor and a co-author of all three papers. "It's just a wake-up call that simply reducing your total dietary fat is not enough."

Uhhh, how about "a wake-up call" that much of what we claim to know about nutrition is snake oil and bullshit and until we have a much better handle on biological processes, especially, say, those that create bloodstream cholesterol, we should probably refrain from prescribing overarching solutions to problems we don't yet understand?

In case people haven't noticed, eating a lot of dietary fats tends to be correllated with overweight. I'm happy to keep my fat (and caloric!) intake low and my fiber intake high, regardless of whether it's going to be some magic bullet that helps me avoid heart disease and stroke (and there is a history of both in my family). I'll eat sensibly (which includes the occasional cheesecake blowout), exercise appropriately (it's really not hard to forget that there are elevators in buildings and take the stairs instead), be observant and get appropriate medical tests (especially after those magic age milestones), and try to reduce stressors and live happily. That's about the best anyone ought to expect to be able to do. Do people really think that's deprivation?

I wonder how correlated it is with overweight. I believe that part of my success in losing weight was due to adding fat into my diet, as it made me feel full faster.

It's also not exactly clear that the current "weigh less" attitude is correct. My impression (and if I have a little time today maybe I'll go try to find the studies) is that there's more longevity if you're a notch or two heavier than the BMI guidelines suggest. Not hugely, but a bit. Of course my impression of the current studies on longevity in rats is that the optimal way to do that is to eat a lot every other day, but my point still stands: There's a lot of bad science that's being published as nutritional fact, and there are a lot of single-issue studies which are being used to promote changes in lifestyle that aren't necessarily supported when multiple studies are examined.

#Comment Re: made: 2006-02-08 18:27:31.832484+00 by: mvandewettering

It's actually incredibly disconcerting to me just how tentative our knowledge of these metabolic processes is. As someone who enjoys hacking the insides of complex mechanisms, I rely on information about how to poke and prod systems to get them to do what I want. Since one of my projects over the last two years has been to attempt to increase my general health and longevity, I've been working on weight loss, down to about 260 from 325, but mostly stalled in my attempts to get below 260. My body just does not like to be below 260. I have no problem maintaining this number with a level of concentration about what I eat that I seem to be able to maintain, but I'm still at least 50lbs over my "recommended" BMI. I know that I should probably add strength training to my regimen to augment the aerobic exercise, but frankly, I already spend too much time exercising...

Anyway... It's interesting. A decade or more ago, fat replaced sugars as the demonized food, and we saw an explosion of low fat foods on the market. And yet, what do we see after a decade of increasing consciousness about fats? Record levels of obsesity. What's up with that? Doesn't it point to the fact that maybe the advice we are giving people may not be the most effective?

#Comment Re: made: 2006-02-08 18:32:06.207023+00 by: mvandewettering

For an interesting perspective on diet, check out Nourishing Traditions: The Cookbook that Challenges Politically Correct Nutrition and the Diet Dictocrats by Sally Fallon.

She examined the diets of many nationalities and ethnic groups that have low incidence of cancers and heart disease, and tried to draw some conclusions about how their diet might affect their overall health. It reinforces the idea that I have which I've expressed as "it's probably okay to eat any food that my grandma would have cooked for me." Grandma's food was prepared from fresh ingredients with minimal preservatives and processing, did not particularly shy away from fats, but rather sought a fairly balanced approach to meals. Almost anything I cook is probably better for me than any Weight Watchers Microwaveable dinner...

What's up with that? Doesn't it point to the fact that maybe the advice we are giving people may not be the most effective?

I suspect "what's up with that" is that a couple decades ago, we didn't spend so much time not-moving, and taking elevators everywhere, and sitting in front of computer screens for entertainment. Yeah, there was TV, but more people were walking places more often and doing more manual labor and activities. There are costs to "the leisure society" (however inaccurate that moniker may have been).

And my observation is that there are far more fast-food outlets than there were 20 years ago, and far more reliance on processed foods.

(Not that I think the contention that we need to know more about nutrition science is wrong!)

Almost anything I cook is probably better for me than any Weight Watchers Microwaveable dinner...

Not to pick on you here :-), but I'll take partial issue with that one, too. *IF* what you cook is prepared with fresh ingredients and not overloaded with thick sauces and cheeses and slabs of fatty red meat, I'll agree, but some of the WW frozen meals aren't any worse for you (and possibly better) than some of the meals I've seen offered as "home-cooked from scratch".

#Comment Re: made: 2006-02-08 20:08:30.364101+00 by: Dan Lyke [edit history]

Diane, I think a few of your assumptions might be up to challenge. For instance:

So far as I can tell from the stuff I've read that seems to be holding up long-term, I think the keys are fresh ingredients (and if ingredients are preserved, use pickling or fermentation, canning slightly behind those, freezing and pressure neutral storage only for short periods), minimal high heat processing on the fats, especially the vegetable fats (it seems that the concern over carcinogens in grilled meats is likely overrated), lots of veggies (partially because they provide bulk and nutrients with a low calorie load), and a reasonable caloric intake which revolves around one large meal for the day, with small meals otherwise (because those studies which started out showing that extreme low calorie diets caused lots of longevity in rats have been expanded to show that regular fasting, ie: skipped or reduced meals, has the same effect).

Except that it's heavily calorically concentrated with no accompanying nutrients or trace elements, sucrose (ie: cane or beet sugar) seems to be a dramatically better sugar for you (especially in terms of insulin reactions) than the fructose/glucose combination of corn syrups or honey, and probably better for you than the invert sugars in molasses. Not that this is going to stop me from the occasional use of honey and molasses (and even corn syrups in certain confections), 'cause those flavors are cool.

Avoid an overabundance of certain veggies. Spinach and amaranth, for instance, are big on oxalates and lead to kidney stones and other insoluble calcium salts, but both are very easy to make a primary part of a high vegetable diet.

But while I'm sure I can go back and dig you up specific cites on all of those conclusions, many of those recommendations fly completely in the face of what we've been taught, what's pushed on us as common knowledge.

And, Mark, in watching various people play with their weight, I partially buy the "we're just not active anymore" argument, but I also believe that some people have physiologies with nutritional needs that aren't getting met and have cravings in trying to satisfy those needs that end up with the side effect of too many calories. Until we start understanding those, some people are just not going to be able to shed pounds. For instance, I'm currently at a BMI of about 22.5 with my naked weight, but last time I went to see a doctor the nurse measured me with my clothes on and made some cluck-clucking noises. However, if I try to go lower (which, given my muscle mass, is probably not a good idea anyway) I get some flat out wacky cravings.

Oh yeah, while I'm killing sacred cows (yummy burgers...), I'm also going to toss out there that I believe that the "low sodium" kick against salt was misguided and probably hurt more people than it helped, given that low salt diets don't actually appear to lower blood pressure and that salt is water soluble, so (except in extremes) ya pee out excess amounts of it anyway.

Without getting too far in all this, it's remarkably simplistic to point fingers at "high fat" and/or "high salt" diets ALONE for our culture's lousy health. Given that, it remarkably simplistic of the study to set out to prove a "low fat" diet ALONE will produce significant results in improving our health.

Logically, one can't intake lots of "foods" whose major source of calories comes from sugar and expect to keep your body healthy, nor can one intake lots of "foods" whose major source of calories is fat and keep a healthy body, nor can one ingest 40 times the RDI of salt and keep a healthy body.

However, one MUST consider lifestyle, eating habits, genetics, and lots of factors when discussing health to make the discussion meaningful. The statement that "reducing your salt intake to 4 or 5 grams a day will reduce your risk of heart attack" might be statistically true as far as it goes, but a better interpretation is that "reducing salt intake likely reduces some risk factors related to heart disease and other health issues, but it is by no means a magic cure."

Historically, we look for quick, simple answers to complex, cultural issues. The folks who designed the study are no execption, but it's likely because they wanted some major grant money and some "good press" from the study and probably not because they don't know the truth which is:

Our longterm high fat/high sugar/high meat/high salt/low exercise lifestyle is deeply culturally ingrained and doesn't produce healthy humans. What life expectancy gains we've made are technological and NOT based upon controllable factors related to diet and exercise. Without significant, longterm changes in SEVERAL lifestyle factors, Americans will NOT be truly healthier as a group.

But the truth would generate TERRIBLE press, so you don't get a $415million grant to study that..... you get a big grant to try to produce something Madison Ave can get behind like "granola bars" or "weight watchers" or "diet coke" or "reduced sodium Campbells soup" or whatever.