When Friends Ask: Why Do
You Avoid Adding Vegetable
Oils?
By John McDougall
Begin by telling them, “The fat you eat is the fat you wear,” and remind them that there is nothing attractive about wearing olive, flaxseed, or corn fat.
* For this reason alone, most of your friends and family should steer clear of so-called “healthy oils” derived from plant-foods. Gaining weight can be expected from consuming high-fat whole foods, such as nuts, seeds, avocados and olives, as well as “free oils,” which are usually purchased in bottles. However, the shared propensity for weight gain is where the similarity between unprocessed plant foods and free oils ends.
I consider whole foods, even those with high concentrations of fats, to be health-promoting. However, people interested in losing weight should avoid nuts, nut butters, seeds, seed spreads, avocados, and olives, since they all serve as sources of concentrated, easy to consume, calories.
When I was growing up we had nuts in their shells as a special treat for Christmas. Now these same nuts come bare-naked, salted, and sometimes roasted in additional oils—and the twist of the lid of the jar brings
effortlessly to your lips (and your hips) handfuls of fat-laden, calorie-concentrated rich food. These same foods, however, may be a welcome addition for growing children and active adults. But they should be used sparingly by most of us.Chemically speaking, free oils are chains of carbon found in a purified state. Extraction processes have removed all of the other ingredients of the whole food. Thus, free oils are no longer intermixed with the naturally- designed and balanced environment of proteins, carbohydrates, vitamins, minerals, and ten thousand other chemicals found originally in the plants.
Free-oils are not food—at best these are medications, causing some desirable effects, and at worst; they are serious toxins causing disease. *The main distinction between fats and oils is whether they’re solid or liquid at room temperature. Oils Are Essential for Health The human body can synthesize from raw materials almost all of the organic compounds needed to build and maintain itself. However, there are a few basic elements that it cannot synthesize. These must be obtained from the food, and include 11 vitamins, 8 amino acids, and 2 kinds of fat. Fortunately, except for two vitamins (vitamin D from the sun and B12 from bacteria), all of these essential nutrients are made by plants and found in abundant quantities in a diet based on whole starches, vegetables, and fruits.
Fats are made of chains of carbon which differ in length, and the number and positions of double bonds (a chemical term for a dual linkage between carbon atoms). Animals cannot create double bonds after the third and sixth carbon on the chain. Only plants can make this arrangement. The result is that only plants can synthesize omega-3 and omega-6 fats. These are referred to as “essential fats.
” We, like all other animals, must get these essential fats directly by eating plants or indirectly by eating animals that ate plants and stored these essential fats in their tissues. For example, fish store the omega-3 fats made by algae—fish cannot synthesize this kind of fat.
Common Fats (fatty acids) Linoleic acid is from plants and is the most common kind of omega-6 fat consumed by people. Gamma linolenic acid is an omega-6 fat from plants, and in an isolated form, is used as a medication. Alpha linolenic acid is from plants and is the most common omega-3 fat consumed. Eicosapentaenoic acid (EPA) is an omega-3 fat made by animals, including fish, from alpha linolenic acid. Docosahexaenoic acid (DHA) is an omega-3 fat made by animals, including fish, from alpha linolenic acid. Linoleic Alpha Linoleic Gama Linoleic Eicosapentaenoic safflower flax borage cold water marine fish sunflower hemp black currant seed
hemp seed canola (rapeseed) primrose
soybeans soybeans
walnut walnut
pumpkin leafy green vegetables
sesame purslane
flax perilla
Essential Fat Deficiency Is Essentially UnknownIn our bodies these plant-derived, essential fats are used for many
purposes including the formation of all cellular membranes, and the
synthesis of powerful hormones, known as eicosanoids (prostaglandins,
leukotrienes, and thromboxanes). Our requirement is very tiny, and even
the most basic diets provide sufficient linoleic acid to meet our
requirement, which is estimated to be 1–2% of dietary energy. Therefore,
in practical terms, a condition of “essential fatty acid deficiency” is
essentially unknown in free-living populations.
*
Essential fatty acid deficiency is seen when sick patients are fed
intravenously by fat-free parenteral nutrition. In these cases, correction of
the deficiency can be accomplished by applying small amounts of soybean
or safflower oil to their skin—giving you some idea of the small amount of
oil we require. Plan on your diet of basic plant-foods supplying an
abundance of essential fats delivered in perfectly designed packages,
functioning efficiently and safely.
*Some people talk about a “relative deficiency” of essential fats created by
a large intake of saturated animal fats, synthetic trans fats (as found in
margarine and shortenings), and/or omega-6 fats compared to their intake
of omega-3 fats, and they believe many of our common chronic diseases
are the result of this imbalance. This is quite different from true essential
fatty acid deficiency which would result in: loss of hair, scaly dermatitis,
capillary fragility, poor wound healing, increased susceptibility to
infection, fatty liver, and growth retardation in infants and children.
Free Oils as Medications
When the oils are removed from their natural environments—for example,
from the seeds of corn, soybeans, safflowers, or flax, or the fruit of an
olive or avocado—they are no longer a food. Yes, they do supply
concentrated calories—but the rest of the original nutrition found in the
plant parts is absent. In this state, the free oils can display powerful
1
2
1
1pharmacological effects—some beneficial and some harmful. This would
be analogous to removing vitamins and minerals from plants and making
supplements. I don’t call supplements food, do you? However, the effects
of concentrated, isolated oils are usually even more potent than those
seen with supplements.
Omega-3 and omega-6 oils inhibit the aggregation of platelets, slowing
down the coagulation of the blood—thus these oils “thin the blood.
” This
well-known property can be beneficial for reducing the risk of a blood clot
forming in the heart arteries—the cause of a heart attack. A common
practice is to take omega-3 (fish or flaxseed) pills to reduce the risk of
heart disease.
Omega-3 and omega-6 oils suppress the immune system, reducing
inflammation. As medications they have been tried in autoimmune
conditions such as rheumatoid arthritis, Crohn’s disease, ulcerative colitis,
psoriasis, lupus erythematosus, multiple sclerosis, eczema, and psoriasis.
Other disorders, such as migraine headaches, Alzheimer’s disease, and
PMS have also been treated. The reports of benefits are variable and often
questionable; as a result, their use has not been well accepted in most
medical practices.
As silly as this may sound, it has been suggested that eating essential fat
may cause people to lose weight. However, a 12-week, double-blind
evaluation of evening primrose oil as an “anti-obesity agent” on 100
women found no significant difference in the weight loss achieved by
those taking primrose oil compared with placebo. Fats (and oils) are the
metabolic dollar stored for the day when food is no longer available. Even
“healthy oils” are moved from the spoon to the flesh with such efficiency
that you should assume every drop you eat makes that journey.
Free Oils as Toxins
3
4
5As with all other medications, there are adverse effects from consuming
free oils, when added from a bottle to meals or taken as pills. The most
obvious adverse effect is people gain weight when they eat even so-called
“healthy oils,
” like olive oil. When 54 obese women in a Mediterranean
country were studied, these women were found to be following a diet low
in carbohydrates (35% of the calories) and high in fats (43% of the
calories). Of the total calories from fat, 55% came from olive oil. My
point: a Mediterranean diet which is loaded with olive oil, rather than
fruits and vegetables, will make you fat.
Omega-3 and omega-6 oils thin the blood, which make a person more
susceptible to bleeding. This side effect from taking essential oils to
prevent a heart attack could become fatal after an automobile accident or
if an artery in the brain were to rupture, such as occurs in a hemorrhagic
stroke.
Do Vegetable Oils Really Prevent Heart Disease?
Common knowledge is vegetable oils are protective against heart disease,
but there is evidence that questions the real life benefits:
Serial angiograms of people’s heart arteries show that all three types of
fat-saturated (animal) fat, monounsaturated (olive oil), and
polyunsaturated (omega-3 and -6 oils)—were associated with significant
increases in new atherosclerotic lesions over one year of study. Only by
decreasing the entire fat intake, including poly- and monounsaturated-oils,
did the lesions stop growing.
Dietary polyunsaturated oils, both the omega-3 and omega-6 types, are
incorporated into human atherosclerotic plaques; thereby promoting
damage to the arteries and the progression of atherosclerosis.
6
7,8
9
10A study in African green monkeys found when saturated fat was replaced
with monounsaturated fat (olive oil), the olive oil provided no protection
from atherosclerosis.
One of the most important clotting factors predicting the risk of a heart
attack is an elevated factor VII. All five fats tested—rapeseed oil (canola),
olive oil, sunflower oil, palm oil, and butter—showed similar increases in
triglycerides and clotting factor VII.
Most likely, the heart benefits of a Mediterranean diet are due to it being a
nearly vegetarian diet. The Mediterranean diet is a good diet in spite of
the olive oil. Omega-3 and omega-6 oils could benefit people with
autoimmune disorders. On the other hand, excessive intake of these fats
may actually aggravate these disorders. More importantly, we need our
immune system functioning at full capacity to fight off infections and
cancer. Free oils have been demonstrated to suppress many natural
microbe killing mechanisms (with a marked decrease in cytokine, tumour
necrosis factor-alpha and interferon-gamma). Free oils may be toxic to
the body tissues. Both omega-3 and omega-6 fats are associated with an
increased risk of opacification of the lens of the eye, resulting in
cataracts.
Research on animals suggests the omega-6 variety of oils is very cancer-
promoting and the omega-3 variety may be beneficial for cancer
prevention. However, this may not be the case. In one animal experiment
on colon cancer, a fish oil diet and a safflower oil diet induced,
respectively, 10- and 4-fold more metastases (number) and over 1000- and
500-fold more metastases (size) than were found in the livers of rats on the
low-fat diet. Other, animal experiments also have shown essential fats to
be cancer promoting. Most importantly, population studies tell us that,
worldwide, the lower the total fat intake, the less the risk of common
cancers, such as breast, colon and prostate.
Practical Ways to Eliminate Oils in Cooking
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19,20
21-23Don’t add vegetable oils when cooking
Use non-stick pots and pans
Brown or soften vegetables in water
Sauté with non-fat liquids
Replace oil in baking with fruit or tofu
Use commercial fat-replacers
Lighten texture with carbonated water
Detailed information on cooking without oil
(https:/ /www.drmcdougall.com/articles/information/cooking-without-oil/)
The Final Step
Not a day goes by that I don’t hear someone say to me, “My diet is
completely vegan, but I am still 40 pounds overweight.
” The oily sheen on
her face and hair are a clear give away that she hasn’t been willing to stop
adding the half cup of extra virgin olive oil to her spaghetti sauce. Many
people fall short of their health and appearance goals because they have
yet to eliminate all the added vegetable oils from their cooking. Eating out
is a major stumbling block. More often than not, even after using the best
communication skills with the waiter, the diner plate still glistens with an
oil slick. Avoiding free vegetable oils is the last important hurdle for people
seeking better health. Take the final step—just say “No” to these really
unessential added oils.
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