Should Butter Be Making a Comeback?

Update, June 16: Time magazine has made the topic of this article its cover story for the June 23, 2014 edition.  The titles are  "Eat Butter," "Ending the War on Fat" and "Don't Blame Fat."  The emphasis is on a historical perspective, the evolution of scientific attitudes and medical advice about dietary fats.  Online, you can access the beginning of the Time article and responses to it on other sites. To access the entire Time story online, you must be a subscriber or become one. 

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Before you sink your teeth into your next steak or butter-laden slice of toast, you may wonder if you SHOULD be enjoying these foods high in saturated fats. If so, you may want to focus on this recent nutrition debate:  Are saturated fats really bad for you or not?

"Butter is Back" is the title of a New York Times article by health food writer Mark Bittman. Let's investigate the study that prompted Bittman's welcoming attitude toward saturated fats. And let's consider some responses from the scientific community.  But first, a quick review of different types of fats.

Which fats are in which foods:

We consume saturated fats when we eat meat, whole-fat dairy products (including butter), baked goods, tropical oils, and chocolate.  Polyunsaturated fats (for example, omega-3 and omega-6) are in fish, nuts, seeds, and vegetable oils.  Monounsaturated fats are in olive oil, canola oil, avocados, and nuts.  Trans fats (which are being phased out) may be in the fried and baked goods you love. However, the University of California, Berkeley Wellness Letter this points out: "The fats in all foods contain both saturated and unsaturated fatty acids." In fact, up to one-quarter of the fat in fish is saturated, and nearly half the fat in meat is monounsaturated.

Saturated fats have long been pegged as the villains that harm the heart, so the main conclusion of this recent study is something of a shocker.

What the study did and said:

This study is a meta-analysis, a study of other studies. The researchers analyzed 72 studies (published over the past 60 years) that focused on fats and their connection to heart disease. The subjects, more than 600,000 people, came from 18 different countries. The researchers focused on the relationship (or lack of it) between various types of fats and coronary events such as heart attacks.  According to the University of California, Berkeley Wellness Letter, "The overarching finding was that there were no statistically significant associations between various types of fat and coronary events."  These were the only exceptions the study found:

• There was a slightly decreased incidence of coronary events from a diet high in the omega-3 fats in fish (but not from omega-3s in plants or supplements).
• Eating a lot of saturated fat did NOT, on average, cause people to have higher rates of coronary disease. 
• Those who ate a lot of poly- or monounsaturated fats (which are supposed to be good for the heart) did NOT have less heart disease. 
• One of the study's authors said that it's important to consider not just the fat grams but the way the body processes them.  For example, a type of saturated fat linked to milk and other dairy products actually reduces heart disease risk, according to Dr. Dariush Mozaffarian.
• The researchers concluded, "Current evidence does not clearly support cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of total saturated fats."  (quoted from the American College of Physicians website)

Bittman's conclusions:

He points out errors we've been indoctrinated with about fat: 

• Polyunsaturated fats, promoted as healthy, may turn out to be "problematic."
• Many of the "low-fat" carbohydrates consumers have been encouraged to eat are "an important factor in our overweight/obesity problem."

Then his article goes on to other matters about what he considers a healthy diet: He opposes eating "hyperprocessed junk" and tells his readers to eat real food and "avoid anything that didn't exist 100 years ago." He considers processed foods that contain many ingredients harmful. His article travels far from the topic it started with: consideration of a study that claims saturated fat may be no more harmful than other types of fat.  But his article did help to call attention to the study and inspire public reaction to it.

Bittman's article and his qualifications to comment upon the conclusions of the study are attacked in this Huffington Post article: "Bittman, Butter, and Better Than Back to the Future."

Responses from scientists:

The medical community's response to the study's conclusions has been, from what I've seen, less than enthusiastic.  Some physicians and associations have said they have no intention of revising their dietary advice to patients based upon this study. They will continue to encourage limiting consumption of saturated fats. The American Heart Association will continue to recommend a diet high in produce, whole grains, fish, nuts, and unsaturated fats. The University of California, Berkeley Wellness Letter says, "Virtually all diets known to be heart-healthy [for example, the Mediterranean diet] tend to be low in saturated fats."

Many don't trust the study's conclusions:

• "Mainly, I think the findings should be disregarded," says Walter Willett, M.D., chair of nutrition at the Harvard School of Public Health.  Although the study implies that saturated fat "is not quite as bad as its reputation, it depends on what you compare it to."  Replacing saturated fat with carbohydrates or refined starch or sugar won't lower your heart disease risk, but replacing it with polyunsaturated fat will, Dr. Willett points out. 
• There have been criticisms of the research method employed by the study, for example, the fact that participants self-reported their fat intake. 
• The University of California, Berkeley Wellness Letter points that, although everyone agrees that saturated fats raise "bad" cholesterol, "this doesn't inevitably lead to increased heart disease. The picture is not so simple, since saturated fats are not all the same, and they are never eaten in isolation."  For example, the saturated fats in chocolate are less likely to increase bad cholesterol than the ones in beef. 

Whether experts take the study's conclusion seriously or not, WebMd says, "All agree that dietary fat is just one factor that drives heart disease risk."

So what about butter?

Use it and enjoy it, says food process engineer Dr. Timothy Bowser: "My family never stopped using butter! Our aim has been moderation but never elimination. We use olive oil when we aren’t using butter. My wife and I both think that butter and olive oil have distinctive flavors that can’t be matched in many foods. With fried vegetables, we like olive oil. In pound cake, butter is better. For me, there’s nothing like butter on a hot biscuit or a pancake. I also love butter in cookies. Butter helps maintain crumb softness and makes flaky crusts. Mouthfeel is a very important quality of butter–it reduces waxiness which may come with the use of other fats.

However, here's some bad news from the Wellness Letter: "Whole-fat dairy products may have heart-healthy effects because of the potassium, calcium and other compounds in them (this is apparently not true of butter.)"  Oh well, I like the taste of I Can't Believe It's Not Butter.

Source(s):

University of California, Berkeley Wellness Letter, "The end of the debate? Fat Chance, July 2014.

annals.org (American College of Physicians, Annals of Internal Medicine) "Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk"

http://annals.org/article.aspx?articleid=1846638

nytimes.com "Butter Is Back"

http://www.nytimes.com/2014/03/26/opinion/bittman-butter-is-back.html?_r=0

huffingtonpost.com "Bittman, Butter, and Better Than Back to the Future"

http://www.huffingtonpost.com/david-katz-md/bittman-butter_b_5042270.html

webmd.com "Saturated Fats Not So Bad? Not So Fast, Critics of New Analysis Say"

http://www.webmd.com/heart-disease/news/20140320/dietary-fats-q-a

Timothy J. Bowser, Ph.D., Oklahoma State University, Dept. of Biosystems and Agricultural Engineering