7.2 Eating Fat
To sum up, the various fats in your food arrive in the form of
saturated, monounsaturated, or polyunsaturated fats, and often a
mixture of all three of these substances.
Olive oil, which you can use in your homemade salad dressing,
contains the following types of fats: monoFats (about 75 percent);
satFats (about 14 percent), and polyFats (about 11
percent).Olive oil’s principal monounsaturated fatty acid is an 18-carbon chain
fat called oleic acid.
Note
Olive oil is a liquid at room temperature. The
higher the number of double bonds in the fat’s chemistry, the more
likely it will be a liquid at room temperature. Animal fats tend to
contain more monounsaturated (one double bond) and saturated fats,
and thus tend to be solid at room temp. Vegetable oils, true to
their name, are only usually liquid at room temp and contain more
polyunsaturated fats.
The health advice for eating fat can be summed up this way: eat
a reasonable amount of monounsaturated fats, as in olive oils,
avocados, and macadamia nuts, as well as fish and many meats, and try
to even out the ratio between Omega 6 fats and Omega 3s.
Saturated fats have recently had the air let out of their tires
as the demon of your diet , so we don’t have to be so
phobic about them. They might even have anti-inflammatory effects for
some people, particularly if you’ve replaced a lot of simple carbs or
sugars with them.
Coconut milk is fine, as are high-quality cheeses and grass-fed
meats, and the satFats you get in the small chunks of the 100-percent
high-cacao chocolate I eat (addictively) are acceptable and healthy
additions to the diet.
Figure 12
shows all the other fats (some in trace amounts) that olive oil
contains, from the handy NutritionData tool. A teaspoon of olive oil
is 100 percent fat by calories, with 5 grams totaling about 45
calories (9 calories per gram, because it’s a fat!).
Figure 12. For olive oil, mostly monounsaturated fat, Omega 6, and
palmitic acid, a saturated fatty acid
This is how you can find out the fat content of your food: do a
search at NutritionData, then scroll down to the boxed area reserved
for Fats & Fatty Acids. This shows that a teaspoon of olive oil
also contains almost half a gram (439 mg) of linoleic acid, or Omega 6
fats, a subset of polyFats. There’s the oleic acid: “18:1
undifferentiated”—more than three grams of it.
I told you those fat notations could get pretty geeky!
Rather than just a teaspoon of oil, let’s analyze the fat
content of typical fare for an American Friday night: a large pizza
slice with pepperoni. The dish sounds delectable, but, like all of
life’s vicissitudes, that dinner’s nutritional profile is likely to be
a mixture of joy and regret.
It wouldn’t be fair if we didn’t indicate the whole lineup of
macronutrients, including protein and carbs. Figure 13 from
NutritionData shows the Fats & Fatty Acids results for a 14-inch
pizza slice with pepperoni topping.
Figure 13. The fatty acid lineup for a slice o’ pepperoni
The pizza slice includes 12.1 grams of fats, or 109 calories,
which happens to be 37 percent of the total 298 kcal.
Note
This is pretty high in calories for just one pizza
slice. Multiple slices would obviously be a very energy-dense meal.
Better be climbing a mountain the next morning, or better yet, back
off from the slices and eat some blueberries.
The macronutrient ratio, the whole shebang, for the pizza slice
is 46 percent carbs-37 percent fats-17 percent protein. You can assume
that the vast majority of the carbs (and thus up to half of all the
calories) came from the refined flour of the pizza crust.
You can see that the pizza slice contains all three fatty-acid
classifications. About 44 percent of the fats come from saturated fats
(we can reasonably assume a lot of that comes from the cheese, since
mozzarella cheese, for example, is about 58 percent saturated
fat).
The saturated fat isn’t necessarily bad (five grams or so,
almost matched by a similar amount of monounsaturated fat) from a
health standpoint, compared with the refined carbohydrate represented
by the pizza crust.
Note
Oh no, here it comes again, some glum preachy advice
about not eating too much pizza! I’m imitating my son here, who’s
heard enough from me about nutrition. He calls me, with a derisive
tone, “Mr. Healthy Guy.”
The crust might contribute to the fat gains brought on by
excessive energy-dense foods. Just ease up on it, do yourself a
favor.