Let's take a look at dietary fats and heart disease.
The good, the bad, and the ugly. You might be surprised to know that the
location of your body fat actually makes a difference in your overall health
outcome. In the health, aging, and body
composition study, researchers looked at 2,500 individuals who are age 70 to 79,
and they found that those who had more abdominal visceral fat had stiffer
arteries than those who had less. It didn't matter whether they were normal
weight, overweight, or obese. So you have different types of fat in
your body. Let's see, you've got subcutaneous fat.
Subcutaneous fat sits pretty close to your skin.
And then this is the visceral fat that they were talking about in the study.
The visceral fat is your intra-abdominal fat.
And it's located within your abdomen, packed between your liver, your kidneys,
and your other organs. And this visceral fat is actually quite
dangerous. Researchers believed that that type of
visceral fat is actually metabolized in a way, in a harmful way, by your body such
that it ends up elevating your liprel proteins.
So, for individuals that have big beer bellies, that's actually pretty
dangerous. Many women who have fat that tends to
accumulate around their butt and their thighs area, that fat, well, they might,
might not like it there. It's actually less dangerous than the fat
that you see located around the middle region.
So, starting with the bad fats or saturated fats.
We call it saturated fats or the ones where there's no carbon-carbon double
bonds. They form straight chains and they're
solid at room temperature. We find them in foods like meat and full
fat dairy. In the United States, the primary sources
of saturated fats do come from meat and full-fat dairy.
But anybody who eats a diet that's high in animal products or high in tropical
oils, so things like palm and coconut oils, is at risk for having probably more
saturated fat than they need. In the US, in case you were curious, the
NHANES study, which is a large national level study that's done to kind of look
at how Americans eat, and how that pertains to their health.
Has found that the following foods are the primary contributors of saturated fat
to the US diet. Regular cheese makes up 8.5% of the
saturated fat consumed in our diet. Pizza, which contains cheese and that's
where the saturated fat is coming from is next.
Grain-based desserts, which would probably have a lot of butter, maybe
lard, maybe other variations of tropical oils, is the third highest contributer of
saturated fat. Followed by diary desserts, because full
fat dairy is a good source of saturated fat.
And then you get into the meat. Things like chicken and mixed chicken
dishes, burgers, sausages, beef. And you can see it kind of goes on from
there. So again, if you're looking to reduce
your saturated fat in your diet, a good way is to really cut back on the animal
products in your diet. Go for lean, low-fat choices.
And especially if you like or eat dairy foods, to really try to eat just non-fat
or 1% reduced fat, to the 1% low-fat dairy foods.
So, what's the research show about the relationship between saturated fat intake
and cardiovascular disease? Well, since so most of the Western or
developed countries, saturated fat intakes comes from meat and cheese, let's
look first at meat. In the National Institutes of Health,
AARP Diet and Health Study, there was a study that looked at the meat intake and
mortality. And it was a perspective study of over a
half a million people. And what the researchers found is that
those who consumed the most red meat, about five ounces per day.
And a good rule of thumb is that if you take this palm of your hand, or roughly a
computer mouse, or a deck of cards that that's about 3 ounces of meat.
So, 5 ounces is you know, one and a half palms or close to two computer mouse
sizes worth of meat. Those people who ate that much each day
were 30% more likely to die of heart disease or cancer over the next ten years
than were those who ate the least red meat.
And the least red meat was just under an ounce a day.
So, those who ate the most white meat, and that's the lean meat for example
poultry and fish, had a slightly lower risk of dying over a decade than those
who ate the least. What's the take away message here?
From a cardiovascular standpoint, it's important to cut back or to cut down on
not only your red meat but also on processed meats.
What's the difference between raw and cooked, and processed and unprocessed
meats? Raw meat reduces by about 25% when
cooked. So, if you had a 4 ounce serving of raw
meat, that would equate to roughly 3 ounces after it's cooked.
A lot of people mistakenly think if they have for example, a high-fat steak that
has a lot of marbling through it, that if they put it on the grill that that fat
will cook off. But that's really not the case.
A little bit of it might, but for the most part, the fat is incorporated into
that final product. So, if you see a piece of beef that has a
lot of white marbling through it, rest assured that that's pretty high in
saturated fat. Processed meat are those that undergone
processing. Usually by adding a lot of salt, perhaps
some nitrates, nitrites, some other additives.
The higher the content of those processed meats in one's diet appears to also
increase cardiovascular disease risk. If you eat meat, do so in moderation, do
so in small portions. Try to eat lean cuts of meat, and try to
stay away from processed and packaged meats.
The USDA has different definitions for meat.
When we talk about lean and extra lean, in the US, lean means no more than 10%
from fat. Extra-lean means no more than 5% of that
is fat. The best option, if you can find it and
afford it, is extra-lean cuts of meat. They tend to be a little bit more
expensive. And they will about, require a little bit
more ingenuity on your part to make them taste good, because of course, there's
less fat in them. Prime is the cut in the U.S, that's the
fattiest. Select is the leanest, and choice meats
are in the middle. When it comes to poultry, some people
think well, I'll just cut out beef and I'll eat chicken instead.
But the type of chicken that you may eat does matter.
Not all chicken is created equal. And if we talk lean cuts of meat, we're
talking about the white meat of chicken and poultry.
That's the breast. If you're going in order from fattiest to
least fattiest, the cuts go: the thighs of chicken are the fattiest, followed by
the wings, then the drumsticks, and lastly the breasts.
The breast is the lowest fat cut of the meat, and the leanest type of poultry.
Ounce perr ounce, these three diets can sometimes give you just as many calories,
fat grams, and saturated fat as you get in your fattier cuts of red meat.
So again, you want to stick to the white meat if you can, if you're trying to eat
lower-fat portions. Also, don't be confused by turkey burgers
and ground turkey. Often times, the ground turkey will
include the meat and the skin. What you want to look for if you're
buying ground turkey is ground turkey breast, because that way you're assured
that it's just the white meat, which is the lean meat.
Sometimes what happens was when people cut out the saturated fat in their diet,
they actually see their triglyceride levels going up, and they get confused.
I thought all of these changes were supposed to bring all of my lipids down.
Reducing your saturated fat is just step one of the equation.
If you take a saturated fat out of your diet by let's say, cutting out burgers
and cutting out cheese and pizza, but you replace it with a lot of white bread and
refined sugars and extra carbohydrates, that's going to increase your
triglycerides levels. The key to helping make positive changes
without seeing elevations in your triglycerides, is to replace your
saturated fat calories with high fiber, whole grains, fruits and vegetables and
legumes, in order to prevent the triglyceride rise.
So, when you cut those fats out of your diet, yeah, you've gotta put something in
there. But the foods that you put back in should
be not refined carbohydrates, but rather high-fiber sources of carbohydrate, like
fruit vegetables, and whole grains. So, all this talk about saturated fat,
what should we be aiming for? Well, 7 to 10%, somewhere in there, is
what's referred to as a heart healthy diet.
What that means roughly for those of us that are eating around 2000 calories a
day is that, that 16 to22 grams a day. To put that in context, one ounce of
cheese, just about a domino size portion of cheese has roughly 5 grams of
saturated fat. So, if you go into the deli and you put
four pieces of regular cheese on your sandwich, that's it, 100% of the
saturated fat for you for the day. In the US, if you use food labels, the
information on the food label is based on 20 grams of saturated fat a day as 100%
of your daily value. Again, if you made that sandwich with
four pieces of regular cheese, it would say 20 grams of saturated fat or 100% of
your daily value. I want to show you a comparison between
whole milk, which is full fat milk, and non-fat or skim milk.
When you make changes in your diet to cut back saturated fat, it doesn't
necessarily mean that you're reducing the other potentially nutritious components
of your diet. One of the reason why some people drink
milk is to get vitamins A, vitamins D, calcium and protein.
One cup of whole milk has eight grams of protein.
It has 6% of your daily needs for vitamin A, 30% for calcium, and it also gives you
about 25% of your needs for vitamin D. But notice that one cup of whole milk
gives you 5 grams of saturated fat. It also gives you 150 calories.
If you make the switch to non-fat milk, which is the same thing as skim milk, you
cut the calories by about 60. Because there's no fat in it, there's
also zero grams of saturated fat. But you still get, 8 grams of protein and
exactly the same amount, sometimes even more of the good stuff, vitamin A, D, and
calcium. So, arguably some people don't like the
way it tastes, or they say it's too thin. But even going down to 1% is a much
better option than eating the full fat milk.
You can see 0 grams of saturated fat kind of frees up some other places in your
diet where you might be able to have a little bit of saturated fat.
You don't need to be getting all of your saturated fat from milk and dairy
products. Trans fats we know, also elevate your LDL
or your bad cholesterol levels. The trans fatty acid is the one you see
here, where the hydrogens are situated across from each other on the
carbon-carbon double bond. You find trans fats in the kind of junky,
high-fat snack foods that you don't need to be eating so much of anyway.
Things like full fat chocolate, full fat dairy foods, and in certain packaged and
processed foods. In the United States, there has been some
interesting civic things done to try and help reduce trans fat intake, and many
health care professionals would argue that these things are working.
We see significantly less trans fat in our diets than even just a few years ago
in the U.S. And the problem is some of these
manufacturers have taken the trans fat out and replaced it with saturated fat.
You know that both saturated fat and trans fats raises your bad cholesterol.
So, replacing one bad thing with another bad thing is not really the solution.
In 2006, New York City placed a restriction on trans fat use in
restaurants. In 2012, there was a survey or study done
that looked at 168 randomly selected New York city locations of 11 different types
of fast food chains. So, 11 companies, but with lots of
different outlets all over New York city. And they interviewed customers who made
purchases in 2007, right after the ban went into effect, and in 2009.
So, they analyzed almost 7000 purchases in 07, and close to 8000 purchases in 09.
And basically, what the researchers found that, although small, there was a
statistically significant reduction in the amount of trans-fat in the choices
that people were making. Frankly, if it's not in your food
anymore, people can't be selecting that. So, there was a reduction in both
saturated fat and a reduction in the combination of trans fat and saturated
fat. It's not great for people to be eating at
fast food restaurants all the time. But due in part to small changes like
this, people are actually a little bit less trans and saturated fat than they
used to. Is it the solution to heart disease?
Of course not. But it's just one of the tools that we
use in public health. Here's your heart healthy fats, your mono
and unsaturated. These include things like avocados,
olives, canola oil and olive oil, peanut butter, sesame seeds and nuts.
There are what we sometimes refer to as the heart healthy diet.
And you'll see that they're a very large component of the Mediterranean diet as
well. If you're interested in learning more
about the fats, it can get kind of confusing.
Saturated and trans fats are not good for me.
Mono and polyunsaturated fats are better for me.
The American Heart Association has put together a relatively entertaining
approach to teaching consumers about fats in the diet.
It's called Meet the Fats. And there's the bad fat brothers, Sat and
Trans. And then the good fat sisters, Mono and
Poly. If you have a moment check, check out
some of those materials to learn a little bit more about these good and not so
great fats that we have in our diet. What sort of research is out there to
prove that the diet changes that we're recommending here can actually change
your lipid profiles. this is a small study, but in 2009 there
was a study of 18 individuals who were encouraged to follow a four week program
of three different diets. Now, these are three diets which if you
live in the US, you may have heard of. They're fad diets that many people have
followed, sometimes more than once. The South Beach diet, the Ornish diet, or
the Atkins diet. Now the problem with looking at these fad
diets and saying are they healthy, is that many people can't stay on these
diets for any extended periods of time. The South Beach diet, if you're not
familiar with it, it's kind of like a Mediterranean diet, low in carb and high
in protein. The Ornish diet is a very high carb, very
low fat diet. And the Adkins diet is a high fat, high
protein, low carbohydrate diet. So when researchers compared individuals
who followed these diets, they found that the South Beach and Ornish diets, which
were low in carb. Well, the Mediterranean one was low in
carb. and they were moderate in protein, but
they didn't have excessively high amounts of fats.
Those reduced the LDL levels pretty substantially.
But if you look at the Atkins Diet, which if very high in meat and high in
saturated fat, in fact, it actually elevated the LDL cholesterols.
So, of course, this is not a very large study, but it does show you that if
you're going to follow some of these diets, a really high fat one is not a
good idea if you're concerned about your heart disease risk.
In addition to studying the effect on LDL, the researchers also worked at
brachial artery testing to measure what's called flow-mediated vasodilation.
And they found an inverse correlation with the intake of saturated fat.
Basically, the more saturated fat you eat, the harder your arteries are
going to be. So, if you're interested in learning more
about dietary fat, I would recommend that you check out some of these websites.
The first two here are from the American Heart Association.
The second of which is a pretty unique fat translator.
You might want to spend some time plugging in your own dietary information.
And then following up with the World Health Organization reference on heart
disease and diet. And then a very informative article from
the Harvard school of public health, about how to make substitutions in your
diet. Tab improved lipid profiles.