Good Fats,
Bad Fats
By Alice R. Laule M.D
If your LDL cholesterol is high, or if you have a free radical-induced disease,
the fats you eat really matter. However, dietary fat is important for all of
us. We can enhance or ruin our health with the quality of fat we eat. There are
essential fatty acids that we must have to stay alive, yet certain types of
fats can weaken the cell structure. Just the topic of supplemental fats (seed
oils, fish oils, conjugated linoleic acid, omega 3 fatty acids, omega 6 and 9
fatty acids) is a huge topic all by itself. I’ll address supplemental fats in a
subsequent newsletter. For this issue, I will just talk about fats we eat.
Any time you hear of a diet that suggests removing almost all of one of the
three primary macronutients (protein, carbohydrates, fats), be wary. No single
group of macronutrients is “bad” for us. The real consideration is the form of
the macronutrients we eat. About 20 years ago, the low protein fad suggested
that protein was a problem. Now we have the low carb craze. In fact, what
matters is the type of protein. One should not get all their protein from red
meat. In fact, the latest data indicates that vegetable protein is better for
maintaining muscle mass in people over 50. And the quality of carbohydrate
matters. One should eat low glycemic index carbohydrates, not those refined
carbs that are divorced from their fiber and mineral content
I’m old enough to remember two low fat diet eras. The first was that of Nathan
Pritikin. Pritikin had his own challenge with early age onset of coronary
artery disease. He found that he could restore himself to symptom free living
with walking exercise, and a low fat diet. However, 25-30 years ago when his
program was very popular, not as much as known about the need for essential fatty acids (EFA’s). His diet was so low in fats that it did not include
enough EFA’s for health. People would thrive and lose weight for about 6 months
on his program, and then their health would start to fail. They were running
out of their storage pool of EFA’s. The original Pritikin program had to be
modified to include a daily intake of EFA’s.
The more recent low fat diet was commercially driven, and deadly. Nathan
Pritikin was, for his time, well informed about nutrition, and taught
people to eat natural, whole foods. The commercial low fat fad offered us low
nutrient foods, high in refined carbohydrates, and may be in part responsible
for the surge in type 2 diabetes. Remember some of those low fat cookies? They
were sure tasty, but each cookie was packed with calories and refined sugars. I
fell into the trap myself, and put away a lot of those cookies!
We’ve established that we need some of each of the macronutrients, and in
particular that we need some fat in our diet. The question becomes, “How much
and what kind?”
The two basic classes of essential fatty acids are the omega 3 fatty acids, and
the omega 6 fatty acids. Anthropological data indicates that the human race
thrived when people ate omega 6 fatty acids that totaled about 5 times the
intake of omega 3 fatty acids. Currently the Standard American Diet contains 20
times as much omega 6 as omega 3. The omega 3 fatty acids overall need to be
increased. Foods that contain omega 3 fatty acids are fish, seeds,
nuts, and some algae. The body uses omega 2 fatty acids primarily in the
form of EPA and DHA. I will space you spelling out the entire lengthy name for
those acronyms.
Most seeds and nuts, including flax seeds, contain another form of omega 3,
which our body must convert to EPA and DHA. Unfortunately, we do not do that
very efficiently. This makes fish the most excellent dietary source of omega 3
fatty acids.
Omega 6 fatty acids are found in vegetable oils, including soy, sunflower,
safflower, and corn oil. Unfortunately, the way these oils are prepared by heat
processing makes a huge amount of our dietary intake of omega 6 fatty acids
harmful. All the EFA’s are polyunsaturated oils, meaning they have a lot of
double bonds between carbon atoms. Those double bonds are fragile, and break
easily. When they are heat processed, they become free radicals. Eat those very
much, and LDL cholesterol goes up, and becomes “oxidized” into a harmful form.
Aging is accelerated, and quite probably the risk of cancer increases.
You may have read that high intake of omega 6 fatty acids is associated with an
increased risk of prostate cancer. I suspect that is because of the form in
which Americans eat their omega 6’s. Namely, we eat too many foods fried in
vegetable oils, heating a fragile oil so that it becomes a damaging
substance.
We also make margarine out of omega 6 fatty acids. Most margarine in the United
States is made by a process which produces “trans– fatty acids.” There is
no unhealthier form of fat that you can eat. The “trans fatty acid”
molecule is a straight, stiff molecule which takes the place in our cell walls
of coiled molecules called “cis fatty acids.” The coiled molecule allows
elasticity and resiliency in the walls of our cells, making them resistant to damage.
The trans fatty acid molecule fits our enzyme systems well enough that it gets
inserted into the cell wall, but makes for a stiff, fragile cell wall. A rather old Australian study showed a many
fold increase in skin cancer in people who ate large amounts of trans fatty
acids. I’d like to see that study repeated. We may find that we could get a
little sun exposure without getting skin cancer, if our diet was better. I
suggest avoiding trans fatty acids as much as possible. There is now a labeling
law, recently in effect, which mandates that the amount of trans fatty acids be
stated. Read labels!
Conjugated linolenic acid is found in organic butter from grass-fed cows. This
actually helps unblock arteries, as well as helping produce increased muscle
mass and fat loss. Yes, saturated fats like butter and other animal fats are
clearly an independent risk for heart disease. But as is true for most foods,
the source matters. Nature puts healing into foods, if we respect her way of
doing things. Even the fat content of beef from grass fed animals is high in
conjugated linolenic acid (CLA). The CLA can be unblocking your arteries even
while you are enjoying some saturated fat in your steak. Eating lots of foods
fried in lard, lots of fatty red meat, or lots of pork (never such a thing as
low fat pork, no matter how lean the cut looks) is still a no-no.
The only oils that are easy to find and safe for frying are olive oil and
macadamian nut oil. Both of these contain omega 9 fatty acids, not an
EFA, but a healthy oil nonetheless. The old saw is, “If olive oil costs too
much for you, then you are frying too much.”
Please let me know if you have questions related to fat intake. You can e-mail
me through the web site. I want to make sure I’m communicating this information
well. It is a huge and very important topic. Next time, we’ll talk about how to
supplement fatty acids. Until then,
Alice R. Laule, M.D.