Choose Wisely for Heart-healthy Fats

Orna Izakson, E/The Environmental Magazine, 16 May 2003

Some environmentally savvy dieticians say that if you can afford to buy
only one organic food item, it should be culinary oils. They base their
assertions on several things, but at the top of the list is the fact
that heavy metals (which can show up in sewage sludge used to treat some
nonorganic farms) and industrial chemicals such as pesticides tend to
stick to fats.

Many common cooking oils — canola, soy, and cottonseed chief among them
— are genetically engineered to withstand more pesticide spraying than
their common counterparts. Although the Food and Drug Administration
(FDA) finds them safe for human consumption, environmentalists are
increasingly concerned about the effects on the ecosystem and on their
bodies. One way to make sure GE plants are not in your food is to buy
organic.

Further, noncertified oils and those not labeled "cold" or "expeller"
pressed may be extracted using the solvent n-hexane, a nervous system
toxin. N-hexane, made from crude oil, primarily raises health concerns
for workers exposed to it as it evaporates. The FDA does approve
chemically extracted oils, but people who choose to buy organic may find
such assurances inadequate.

Critical Building Blocks
Despite the real concerns about too much fat in modern diets, the right
amounts of the right kind of high-quality oils are critical for health.
Fats make up the building blocks of hormones and are especially critical
for babies as they develop their nervous systems, since the oils help
coat growing nerve cells.

"Oil is very important," explained Dr. Chris Meletis, a naturopathic
physician and dean of the National College of Naturopathic Medicine.
"Without oil, there's increased inflammation, altered immunity, and
increased menstrual cramps." He said fats "are critical for the creation
of every cell."

Fats have gotten a bad rap because two kinds — saturated and transfatty
acids — feed heart disease. Saturated fats come from both animal and
plant sources. Oils with high saturated content are generally solid at
room temperature: Think of coconut and palm oils, or butter and lard.

Transfatty acids occur when oils are modified to make them solid at room
temperature, as in the case of margarine. That process, known as
hydrogenation, also reduces or eliminates many of the healthy components
of the oil.

Dietician Connie Diekman, director of university nutrition at Washington
University, says transfatty acids and saturated fats cause the same
kinds of heart-health problems. She recommends using oils in lieu of
hardened fat whenever possible. That might make for a denser cake, she
says, but the health benefits are worth it.

But other types of fats are critical to good health. Monounsaturated
fats actually help undo the heart-blocking effects of saturated fats.
Olive, canola, peanut, sesame, almond, apricot, avocado, and high-oleic
safflower and sunflower oils each have more than 50 percent
monounsaturated fats, according to Spectrum Naturals, a leading oil
distributor.

Polyunsaturated fats, composed of Omega-3 and Omega-6 fatty acids, also
have some cholesterol-lowering properties. They are also the most
important oils nutritionally, because the body can't synthesize them.
But getting the right balance isn't always easy.

Most dieticians say the body needs two or three times as much Omega-3 as
Omega-6. (This is bad news for hemp advocates, since their oil has the
reverse ratio.) Common culinary oils such as canola, corn, safflower,
sunflower, walnut, sesame, and soy are rich sources of Omega-6 but offer
little if any Omega-3. Canola and hemp both have better ratios but
remain relatively heavy on plentiful Omega-6.

Flax seed oil is the best vegetable source for righting the Omega-6 to
Omega-3 imbalance, with a ratio reverse that of hemp. Fish such as cod,
salmon, and mackerel are also excellent sources of Omega-3s. Their oil
is available in supplements but also survives cooking in the meat.
Plant-based sources should not be heated.

Care and Handling
All oils need to be protected from heat and light, which oxidize them
and make them rancid. Oils high in Omega-3 are particularly sensitive
and should be refrigerated.

Aside from smelling and tasting bad, rancid oils are high in free
radicals, said Jim Gallagher, a professor of nutrition at Bastyr
University. Free radicals bond to protein layers in the body and break
them down, leading to a host of health problems.

Oils can go rancid over time simply by exposure to air, so Gallagher
recommends buying oils in small quantities so they are used quickly.
Bulk bins often leave oils exposed to oxygen, but if the oil sells
quickly it will have little time to develop problems. Clean containers
well so you're not adding good oil to rancid remnants.

Heating oils speeds the oxidation process, which is one reason fried
food is bad for you. Burned oils — those that start to smoke — can be
downright dangerous: "A lot of oils when they get superheated turn into
cancer-causing agents," Meletis said. That's true of burned popcorn oil
and the smoking oil that comes up from the coals during a barbecue.

To avoid such problems, choose the right oil for the job. For high-heat
frying, searing, and browning at temperatures up to 500 degrees
Fahrenheit, Spectrum Naturals recommends super canola oil, almond,
apricot kernel, high-oleic safflower or sunflower, peanut, or soybean
oils. For stir frying and baking below 375 degrees, try canola, walnut,
sunflower, or sesame. Use olive, corn, or any of the higher-heat oils
for sauces, baking, or light sautéing under 320 degrees. Save flax,
hemp, wheat germ, borage, and black currant oils for salads or for
drizzling on foods after cooking.

The Canola Controversy
Canola oil — made from the seed of a broccoli relative unfortunately
named "rape" — has become controversial among health food advocates in
recent years. The debate began with an article in Perceptions magazine,
which describes itself as "dedicated to the wholeness of life and
sovereignty of the human being." The article made several claims,
including that canola is an industrial lubricant and a carcinogen.

According to the FDA, rape plants (also known as wild mustard) were
grown for centuries in Central Europe, and oil extracted from the seed
was used extensively in Canada during World War II as a substitute for
scarce petroleum lubricants. But animal studies of long-term
consumption of rapeseed oil linked one of its constituents, erucic acid,
to heart lesions. Canadians began cross-pollinating the rape plants
and, by the 1970s, developed a variety that contains less than 2 percent
erucic acid. That oil, known as Canadian oil or canola, is what appears
on supermarket shelves today.

No one contacted for this story could link canola to cancer beyond the
concerns associated with overheating. Some of the concern appears to be
a misunderstanding of the difference between hybridization (the kind of
cross-pollination that developed corn larger than a finger or wheat that
doesn't shatter until it's ready for harvest) and genetic engineering,
which uses laboratory procedures to add genes that were never naturally
present in the plant. Canola has been the subject of both kinds of
modification, first to lower erucic acid levels and then to increase
pesticide resistance. And while pesticide-heavy, genetically engineered
canola is a concern for many people, organic varieties are free from
both.

Cindy Moore, director of nutrition therapy at the Cleveland Clinic
Foundation, recommends canola oil because it has low saturated fat
levels, a good balance of mono- and polyunsaturated fats, and even
contains up to 10 percent Omega-3. It takes the heat of baking and
mid-range stir frying.

Meletis of the National College of Naturopathic Medicine won't weigh in
on the controversy himself but said he opts for olive over canola. He
said, "I never suggested canola even before the controversy because the
Mediterranean diet has been proven to be heart friendly and generally
promotes overall good health."

Orna Izakson uses natural oils in Portland, Ore.

News Source: E/The Environmental Magazine


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