May 26, 2008

You Ask, I Answer: Saturated Fat

You mentioned that saturated fat is the "bad" fat and this definitely is the common understanding these days.

Have you read any conflicting evidence about this?

After reading the first half of Gary Taubes'
Good Calories, Bad Calories I came to the conclusion that saturated fat really isn't a big deal unless you're in the extreme heart disease risk category, which, at 27 and with normal cholesterol levels, I don't think I am.

And, while I don't agree with Taubes' anti-carb approach, I found his evidence about regarding the fat-cholesterol link (and how research was so highly influenced by politics, guesswork, and some key personalities) very interesting, and moderately convincing.


It seems that cholesterol levels are only veeery minimally affected by saturated fat in one's diet.


I'm wondering how you feel about this aspect of his argument, or if you've seen other people calling the evilness of saturated fat into question recently.


I thought I had it all figured out, but this is the one thing I'm still not sure about.

Thanks so much.

-- Meredith (last name unknown)
Via the blog


Gary Taubes is certainly not the first -- or only -- person to question the saturated fat/heart disease connection.

Although some studies date as far back as the 1950s, Mr. Robert C. Atkins brought the research out of the scientific community and into the mainstream.

He -- along with his proteges -- claimed that eating endless amounts of steaks, butter, and bacon actually led to healthier lipid profiles than low-fat, high-carb diets.

And so we come back to the issue of flawed logic. Let me explain.

Like Atkins, Taubes and his ilk approach this scenario from a very narrow "black or white" perspective.

Firstly, they are quick to judge detractors as low-fat advocates.

This is grossly inaccurate. For instance, I strongly disagree with Taubes, but a quick browse through this blog makes it clear I do not advocate low-fat diets.

Instead, I believe that an adequate amount of the right fats is crucial for our health.

I fail to understand why Taubes and his supporters practically worship saturated fat but completely fail to mention the health benefits of monounsaturated fats and omega-3 fatty acids.

They aren't saying "fat is healthy; make sure to include almonds, olive oil, and wild salmon in your diet!" Instead, they pretty much push red meat and bacon.

Mind you, current guidelines do not call for a complete elimination of saturated fat from the diet; they simply suggest no more than 20 grams a day (assuming a daily intake of 2,000 calories).

Many dietitians -- myself included -- recommend a low intake of saturated fat, but simultaneously urge people to seek out the healthy fats found primarily in salmon, olive oil, walnuts, flaxseed, and avocados.

Although there are some professionals who advocate very low-fat diets -- Dean Ornish comes to mind -- many of the dietitians I know do not support skimping on healthy fats.

Now, when you compare a high-fat (in this case, saturated fat) low-carb diet to a high-carb (conveniently, high in refined carbohydrate), low-fat diet, the high-fat diet will lead to a better lipid profile (triglycerides, for instance, are related to refined carbohydrate intake, not dietary fat).

This, however, is misleading.

It's akin to only comparing bronze (diet high in refined carbohydrates and low in fat) and silver (diet high in fat, albeit saturated, but low in refined carbohydrates) and claiming silver to be the most expensive metal.

Yes, the most expensive of the two.

But, bring in platinum (a diet low in saturated fat but high in mono unsaturated fats and whole grains) and suddenly silver doesn't look quite as amazing.

I would like Gary Taubes to compare two high-fat diets (one high in saturated fats, one high in mono and polyunsaturated fats) and conclude, with a straight face, that the saturated fat-rich one is the healthiest.

There are literally hundreds of human clinical research studies showing a correlation between saturated fat intake and heightened coronary heart disease risk.

One interesting one was published in the July 2005 edition of the British Medical Journal.

Turns out that, in 1991, the Polish government stopped subsidising foods high in saturated fat.

Eleven years later, "deaths from coronary heart disease had dropped by over a third in the 45-64 age group - a 38 per cent drop for men and 42% for women."

During this time, saturated fat consumption fell by 7 percent, and -- more importantly -- polyunsaturated fat consumption increased by 57 percent!

We again come back to the notion that the key is not in reducing total fat intake, but in replacing saturated fats with healthier varieties.

Taubes happily bashes anyone recommending a low-fat diet, but what are his arguments against replacing saturated fats with Omega-3 fatty acids (a type of polyunsaturated fat) for improved lipid profiles?

Moving on to red meat, there is also a good deal of research showing that colon cancer risk is indeed affected by red meat consumption (this 2006 meta-analysis from the Pakistan Journal of Nutrition summarizes some major findings well).

A great Italian study by Talvani et al in 2000 also looked at red meat intake and cancer risk.

I recall Mr. Taubes scoffing and referring to all this evidence as "questionable" when he was on Charlie Rose several years ago.

How he came to that conclusion I do not know.

In my mind, sanctifying saturated fat and telling people to eat it liberally is irresponsible.

By the way, this idea that advice to eat less red meat is some sort of conspiracy relating to politics is rather laughable since, as Marion Nestle brilliantly explains in Food Politics, the national beef association threw a major hissy fit when Dietary Guidelines originally urged the public to simply "consume less red meat".

They were quickly changed to "choose lean cuts of meat," so as to not offend the powerful beef lobby.

We come back, as always, to the issue of moderation.

Have a slice of Swiss cheese here and there or pour a splash of whole milk into your morning coffee if it makes you happy; just don't make saturated fats the main players of your diet.

6 comments:

Anonymous said...

Andy,

I know you saw him speak at your school, but if you're going to post blog entries in which you criticize his work, perhaps you should actually read the book, no? There is a lot more data and arguments in the book than he could have fit into a lecture.

Anonymous said...

Andy,

You said, "I fail to understand why Taubes and his supporters practically worship saturated fat but completely fail to mention the health benefits of monounsaturated fats and omega-3 fatty acids."

In the above you attribute extreme viewpoints to your opponents to discredit their opinions. Really now! We who don't believe saturated fats constitute a health hazard do not worship or ignore fats. We simply try to put them in their proper dietary perspective. In the case of saturated fats, they have been maligned for forty years by public health, the food manufacturing industry, government agencies, vegetarian activists, the American Dietetic Association, and virtually every major health promotion organization in existence. This is a fact. This is not my opinion.

Saturated fats are, in truth, beneficial. The body converts carbohydrates to saturated fats to burn for energy. Animals of all sorts make saturated fats in their bodies to burn for energy and to use for building cell structure.

David Brown
1925 Belmar Dr
Kalispell, MT 59901
Nutrition Education Project
Blog: http://nutritionscienceanalyst.blogspot.com/

Andy Bellatti said...

Anonymous: I do not claim to have read "Good Calories, Bad Calories."

However, prior to answering Meredith's question, I read Taubes' articles relating to saturated fat and read/watched twelve different interviews where he talks about the topic.

At no point does he talk about monounsaturated fats or Omega-3's.

How someone can claim to be a nutrition journalist and apparently ignore monounsaturated fats and Omega 3's is very puzzling to me.

Additionally, he tends to fall back on a "my theory vs. conventional low-fat dogma" argument that isn't relevant since, as I mentioned, dietitians encourage the consumption of mono and polyunsaturated fats.

Taubes clings to this notion that those who do not agree with him are carb-lovers who want people to lower saturated fat intake and eat more white flour.

Andy Bellatti said...

David Brown:

The accusation that I am "attribut[ing] extreme viewpoints to [my] opponents to discredit their opinions" is ironic considering that Gary Taubes uses that tactic often.

I have never heard him acknowledge that most of the nutrition community is NOT pushing low-fat diets.

It is one thing to have diet books (NOT written by Registered Dietitians) saying low-fat is best, but they do not represent the nutrition community.

I do not agree with Taubes' views, but where on my blog do you see me urging people to shun fats?

I'm not sure how the "food manufacuring industry" has been maligning saturated fats. Many food products offer it in substantial amounts.

if anything, don't you find it interesting that so many different entities (the government, 'vegetarian activists', food companies) with varying interests all agree on limiting saturated fats?

"The body converts carbohydrates to saturated fats to burn for energy."

No. Carbohydrates are converted to glucose.

Again, Taubes and his supporters need to think outside the box and realize that many dietitians (and myself, as a future Registered Dietitian) are NOT suggesting replacing saturated fat with carbohydrates, but rather with healthier fats.

"Animals of all sorts make saturated fats in their bodies... use for building cell structure."

That's cholesterol you are thinking about, not saturated fat.

Unknown said...

Gary Taubes doesn't "claim to be a nutrition journalist." He is a science journalist, and has discussed, over and over, his interest in studying bad science -- and bad science is what he wrote about in Good Calories, Bad Calories.

Andy Bellatti said...

Joanna,

I'll grant you that Taubes knows plenty about physics, but just how much time has he spent studying nutrition, biochemistry, or human physiology?

I don't mean looking at research articles that fit his theories, but actually studying the science of nutrition?

How can he be expected to correctly interpret clinical nutrition studies without the proper academic background?

If I tried to read research on physics or engineering, I would be at a great disadvantage because I am not familiar with the topic.

It's hard to sit here and listen to Taubes critique of "bad science" when one of his infamous claims is that exercise does not lead to weight loss, but actually weight gain in many cases!

Conveniently, Taubes based this conclusion on studies relating to one form of physical activity -- swimming.

I would love for him to explain how Lance Armstrong's physique, seeing as how he consumes a very high amount of simple carbohydrates prior to a race and works out vigorously (according to Taubes, vigorous workouts lead to increase hunger).

I know I am not going to change your mind or his, but it's not going to stop me from sharing my thoughts.