More evidence that saturated fat has been falsely accused?

Wednesday, August 19, 2009 16:24
Comments Off on More evidence that saturated fat has been falsely accused?

What if cancer, heart disease, and diabetes are really all the same disease?

An excellent commentary in this month's issue of the Journal of the American Dietetic Association lays out a compelling and detailed map showing how obesity and insulin resistance interact to promote the growth of cancerous tumors. The authors argue that weight loss (if appropriate) should be a central feature of cancer prevention and treatment. Going a step further, the journal's editors suggest that obesity (and insulin resistance) is the common culprit in all of the Dreaded Three: cancer, diabetes and heart disease. 

Now, if you ask the dietary establishment how to prevent obesity, cancer, and heart disease, they will most likely advise you to reduce your intake of total fat, saturated fat, and red meat. (See, for example, the American Cancer Society, the American Institute for Cancer Research, and the American Heart Association.)

Yet another study in the same issue of JADA tells a different story:

Saturated fat and red meat seem to prevent expanding waistlines

Danish researchers studied the links between consumption of various food groups and change in waist size.  Why are they worried about waist size? An increase in waist size signals an increase in visceral, or abdominal, fat. This is considered the most dangerous pattern of weight gain because abdominal fat is strongly linked to increased risk of heart disease, cancer, insulin resistance, and diabetes.  In fact, the association is so strong that a waist measurement of more than 35"  (for women) or 40" (for men) is an independent risk factor for heart disease.

Surprisingly (to some), they found that women who ate more butter and high fat dairy products gained less weight around the waist than those whose diets are lower in saturated fat. A similar association was observed with red meat–that is, those who ate more red meat had smaller waistlines. The researchers seem to be at a loss to explain these findings.

Some would argue that a diet higher in fat and protein may be lower in carbohydrates and that carbohydrates drive insulin resistance and obesity.

No consistent link found between animal fat and breast cancer

Then there was this study in the American Journal of Clinical Nutrition: Researchers from several European countries collected and analyzed dietary records for 319,000 women and found "no consistent association" between the consumption of eggs, meat, or dairy products with breast cancer. This, of course, contradicts previous observations.

I'm reminded of our extended debate over whether or not eating red meat increases your risk of cancer. And many of the same observations apply here: trying to draw definitive conclusions about the impact of diet on disease using diet records is a very tricky proposition. It's possible that red meat may be a red herring. For one thing, any category that lumps a char-grilled fast food hamburger (and the fries likely to accompany it) together with a grass-fed bison filet is completely meaningless.

Should you start eating more meat?

I'm not making any blanket recommendations one way or another.  Some thoughts:

The prevailing wisdom that meat and saturated fat are unhealthy is based on the same sort of inconclusive, circumstantial evidence as the studies I've noted here.  But if we really want to get to the truth, we're going to need to consider ALL the (flawed) evidence, not just that which supports our point of view.

As many of you know, I'm not a big meat eater myself–although this is more for environmental, ecological, and ethical reasons than nutritional concerns.  But I'm pretty sure that no one food or group of foods causes disease. In fact, to circle back to the beginning of this post (and a recurring theme around here), it seems that plain overconsumption of food in general is a bigger problem.  The fact that so much of that food is over-processed and nutrient-poor sure doesn't help.

If you're eating a calorically-appropriate diet made up mostly of whole foods, I'm prepared to be pretty darned flexible about the details.

Both comments and pings are currently closed.