Living Low Carb (15 page)

Now, if your first thought on reading the above argument was “
Well, sure, that makes sense
,” it’s only because you’ve heard this argument so many times that you no longer question whether any of it is true. The association of fat and heart disease has become what philosophers call a “meme”—a generally accepted cultural notion that is deeply embedded in the national consciousness. To question it almost puts you in the category of the crowd with the tinfoil hats.

Hence this chapter. Because we’ve been taught so much gibberish about fat, and because the
fear
of fat is intimately entwined with
both
the fear of cholesterol
and
the general prejudice against low-carb diets, arming yourself with some basic info on fat may help you understand why a higherfat diet is nothing to fear. Sure, the “conventional wisdom” says otherwise, but in this case the conventional wisdom is only conventional. It is anything
but
wise.

Bear with me if you already know this stuff—and even if you think you do, it’s probably worth reviewing. I’m going to question some widely held beliefs now, including some choice tidbits of information you may be sure are true, but remember—sacred cows make the best burgers!

And one more thing: I promise to make this short and sweet, and my mission is to write it in such a way that your eyes don’t glaze over.

Interested? Read on.

A Brief Primer on Fat

“Fat” is actually the general, colloquial term for a collection of smaller units technically (and properly) called
fatty acids
. Each of these fatty acids has a team identity—it belongs to a
group
(saturated, unsaturated). When we call something like butter or olive oil a “fat,” what we actually mean is that it’s a
collection of individual fatty acids
. (When a food is “high in fat,” that just means it’s got a lot of fatty acids in it.)

Almost all fats in food are some combination of the three main types of fatty acids—saturated, monounsaturated, and polyunsaturated—although we tend to identify a fat in food by the type of fatty acid that’s
predominant
in the mix. For example, many foods that we call “saturated-fats foods” (like butter or steak) actually contain many “unsaturated” fatty acids, and most foods that we call “unsaturated fats” (like olive oil) contain some “saturated” fatty acids as well. And sometimes the mixture is actually quite different than you might think. (Would it surprise you to know, for example, that a typical sirloin steak has more
monounsaturated
fat than it does
saturated
? Or that fish oil—the ultimate unsaturated fat, and an omega-3 to boot—is about 25% saturated fatty acids? Both are true.)

In addition to belonging to one of the three major “groups” of saturated, monounsaturated, or polyunsaturated fats, each individual fatty acid also comes with a molecular description (don’t ask), and a name (e.g., stearic acid, lauric acid). This is important because some individual fatty acids have important health benefits and have distinct effects (or no effect) on the body. Lauric acid, for example, is a saturated fatty acid found in coconut that has immunesystem– boosting properties—it’s both anti-microbial and anti-viral. Stearic acid, another saturated fatty acid, has virtually no effect on cholesterol.

Every single fatty acid on the planet—regardless of whether it’s saturated, monounsaturated, or polyunsaturated—is basically a
chain of carbon atoms
linked together by chemical bonds. Think of a little row of circles (carbon atoms), holding hands. You can also imagine these chains of carbon atoms as a bunch of little school kids on a day outing, joined together with one of those ropes that kindergarten teachers use when they take their kids on a field trip.

Now just as each of those kids in the kindergarten class has two arms which can “hold” something (like a book bag), each carbon atom has two “places” to which something can attach. In the case of the carbon atom, the only “thing” that can attach to those places are hydrogen atoms.

When all the “places” to which hydrogen atoms can attach are “filled” (i.e., “no seats left on the train”), the fatty acid is said to be “saturated.” It’s literally
saturated
with hydrogen. There’s no more room at the table, so to speak. The places on the individual carbon atoms in the fatty acid are basically all occupied, so the fatty acid can’t hold any more hydrogen passengers. (Trans-fats are a kind of “hybrid” saturated fat that’s basically created in a lab by taking an “unsaturated” vegetable oil and blasting it with hydrogen atoms from the chemical equivalent of a turkey-baster, forcing some hydrogen into the empty seats and producing “partially hydrogenized vegetable oil”—or, as I like to call it, poison.)

Are you with me so far?

Good. Now, when there is one seat or more that’s “unoccupied” on that chain link of carbons, the fatty acid is called
un
saturated—there are still places that could be occupied by hydrogen atoms. In other words, it’s not yet a “full house.” (If there’s only
one
spot “open,” it’s called a
mono
unsaturated fatty acid; and if there’s
more
than one spot “open,” it’s called a
poly
unsaturated fatty acid. More on that in a moment.)

So what happens when there’s still “seating” on the carbon chain? Well, instead of holding on to two hydrogen atoms, that carbon atom takes its two empty hands and creates what’s called a “double bond” with the next carbon in the chain. (Think of each school kid in the line holding
both hands
of the kid facing him. And because both his hands are now occupied, he can’t hold anything else.) When there’s just
one
such
double bond
in the chain, the fatty acid is called a—can you guess?—
mono
unsaturated fatty acid.

Fat Architecture

Now let’s clear up all this stuff about “omegas.” In fatty acids, as in real estate, there’s one rule—location, location, location. Recall that if there’s only
one
double bond in our little carbon atom chain, we’re dealing with a
mono
unsaturated fatty acid. And if the
location
of that single double bond is on the 9th carbon counting from the end of the line, it’s known as an
omega-9
fatty acid. How simple is that? The most famous omega-9 (monounsaturated) fat is olive oil, believed by just about everyone to be a “healthful” fat.

Poly
unsaturated fatty acids simply have
more than one
double bond (hence the name “poly,” which means “many”). Those that have their
very first
double bond on the 3rd position (counting from the end of the line) are called
omega-3’s
. Those that have their very first double bond on the 6th position (again counting from the end of the line) are
omega-6’s
.

Okay, just in case your eyes are glazing over, there really
is
a good reason to know this stuff, and it’s this: omega-6’s and omega-3’s are
building blocks
out of which the body makes distinct compounds (called
prostaglandins
or
eicosanoids
) that have different—and opposite—effects. For example, omega-3’s are the building blocks for
anti-
inflammatory prostaglandins. Omega-6’s are building blocks for
inflammatory
ones.

You might think, hey, if omega-6’s make inflammatory compounds, what do I need them for? Good question, and here’s the answer: you need them because inflammation is a natural part of the body’s healing response. Let’s say you injure your foot by stepping on a nail. What happens? Your foot swells up, because the body mounts a defensive reaction to that injury. Fluid and white blood cells rush in to surround the area, hoping to destroy any pathogens or bacteria that might have gotten in the wound, in an attempt to prevent an infection. You
need
the building blocks for that inflammation response
¹
in your body, or you wouldn’t have great “defenses” against what the body perceives as an attack.

But those inflammatory and anti-inflammatory prostaglandins need to be
in balance
in order for you to have an optimally functioning body. If your “pro-inflammation” factory is working overtime and your “anti-inflammation” factory is understaffed, you’re in deep doo-doo. And that’s exactly what’s happened to most people eating a Western diet, which now has a ratio of about 20:1 in favor of omega-6 to omega-3. (The ideal ratio is between 1:1 and 4:1.)

You can’t swing a rope without hitting an omega-6 fat—they’re everywhere in our diet. Corn oil, soybean oil, vegetable oil, safflower oil, canola oil—all high in omega-6’s. Those of us who have been taught the mantra “saturated fat
bad
, vegetable oil
good
” might think for a minute about consuming huge amounts of “unsaturated” vegetable oils without an appropriate amount of anti-inflammatory omega-3’s to balance that intake.

You might think inflammation is no big deal, but you’d be making a huge mistake. Most of us are walking around with low-grade inflammation in our bodies that flies below the radar. Inflammation damages our vascular and circulatory systems and contributes to virtually every degenerative disease known to humankind, from heart disease to Alzheimer’s, from cancer to diabetes. Not for nothing did
Time
magazine do a cover story called “Inflammation: The Silent Killer.” There’s a good deal of emerging evidence, by the way, that controlled-carb diets—even those higher in saturated fat—actually
lower
inflammation in the body.
²

Here’s something else to think about: we’ve done such a good job of demonizing saturated fat that it’s effectively been replaced in our kitchens (and in fast-food restaurants) with the supposedly more healthful “vegetable” fat, most of which is stunningly high in omega-6’s. The problem is that omega-6’s are “unstable” fats. When used (and reused) for frying as they are in most fast-food restaurants, they actually get badly damaged and create carcinogenic compounds. Researchers at the University of Minnesota have shown that when unsaturated (omega-6) vegetable oils are heated at frying temperature (365° F) for extended periods—or even, for goodness’ sake, for a half hour—toxic compounds will form. One in particular—HNE—is associated with a number of very bad chronic diseases that you really don’t want to have.
³

Saturated fats—because they are highly
stable
—do
not
create these toxic compounds when heated to high temperatures. Many people who really understand fat chemistry will tell you that they would much prefer deep frying in real lard (not Crisco!) to reused canola oil any day of the week. It’s far less damaging to the body. (My favorite oil for cooking at high temperatures in a wok or frying pan is Barlean’s organic coconut oil.)

In addition to creating toxic compounds when heated repeatedly, vegetable oils used by fast-food restaurants often contain
trans-fats
, probably the most damaging fat on the planet (and one whose dangers dwarfs the supposed dangers of saturated fat). Up until very recently, foods like margarine were loaded with the stuff. Kind of ironic, isn’t it, when you think that the whole reason for the popularity of high omega-6 vegetable oil products like margarine was the desire to eliminate the “dangerous” saturated fat from our diet—talk about the “law of unintended consequences”!

So we have nothing to fear from a higher percentage of fat in our diet, particularly when it’s “good” fat—by which I mean fat that has
not
been damaged by repeated high heat, fat or oil that is
not
highly refined (like some cooking and vegetable oils), and
all
man-made trans-fats. Some coldpressed unrefined omega-6’s in the diet are fine, omega-9’s are fine, omega-3’s are better than fine, and—yup—
saturated fat is fine too
, especially when it comes from whole natural foods such as eggs, coconuts, organic butter, and the like.

Now, here’s an interesting factoid about fats: the only fatty acid that the body actually
makes
is palmitic acid—a saturated fat! Then it takes that palmitic acid and gets to work on it with a system of enzymes. It adds carbons, thus
lengthening
the chain—these enzymes are called
elongases
(they
elongate
the chain). It also
removes
pairs of hydrogens from some of the carbons that are saturated, thus creating new double bonds. The enzymes that do this are called
desaturases
(by removing some of the hydrogen passengers, they turn that saturated fat into an unsaturated one). Through this system of elongases and desaturases, the body—starting with saturated fat—winds up with a whole menu of fatty acids to serve different purposes. (We also get a variety of different fatty acids directly from our diet—like, for example, omega-3’s directly from fish or flaxseed.)

If saturated fat were inherently so bad for us, why would it be the very fat our body makes naturally from food?

Saturated Fat and Heart Disease: What’s the Real Connection?

In the context of today’s conventional wisdom, it almost sounds ludicrous to put that question out there, so deeply accepted is the idea that saturated fat and heart disease are married forever in some metabolic Universe of Bad Things. But more and more researchers are asking that identical question, and the ones who are looking honestly at the data are not so convinced that the conventional wisdom is right. In 2008, the American Society of Bariatric Physicians, in conjunction with the Metabolism Society, presented an entire two-day conference in Arizona named “Saturated Fat and Heart Disease: What’s the Evidence?”