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ment is similar in human infants. This is discussed lower. Researchers at the University of Wisconsin Madison first tried to
in more detail in the sidebar below. The essential produce essential fatty acid deficiency in adult rats in 1947. The only way
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fatty acid requirement, however, is influenced by they were able to induce a deficiency was to starve the rats until they lost half
other factors. The refined sugar used in these ex- their bodyweight. As they gained back the weight they had lost over the sub-
periments increases the requirement. Vitamin B sequent two months, they developed typical symptoms of essential fatty acid
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alone resolved the deficiency in later experiments deficiency such as scaly skin and hair loss. A small amount of corn oil proved
by dramatically increasing the synthesis of arachi- curative, but even in the deficient rats the symptoms disappeared when they
donic acid from linoleic acid stored in the tissues. returned to their original weight. It thus appears that most of the arachidonic
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Diets low in refined sugar and rancid vegetable oils, acid required during growth is used to supply dividing cells with enough to
adequate in protein and total energy, and rich in store in their membranes, and to form junctions between newly generated
vitamin B , biotin, magnesium, and whole, fresh cells. Adult rats, by contrast, can probably meet their much smaller needs for
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foods abundant in natural antioxidants are likely to arachidonic acid even when they go long periods without any essential fatty
reduce the essential fatty acid requirement to such acids in the diet by synthesizing it from the linoleic acid they have stored in
a degree that it is impossible for a healthy, growing their tissues.
child under ordinary circumstances to develop a George Burr’s first human guinea pig was his good friend and distin-
deficiency. guished colleague Jesse F. McClendon. McClendon is best remembered as
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The requirement in adults is likely to be even the first researcher to directly measure the pH of the human stomach, but

HOW ESSENTIAL ARE THE ESSENTIAL FATTy ACIDS? A MORE DETAILED LOOK

The requirement for essential fatty acids is, under most conditions, exceedingly small. This should not be surprising;
after all, if we require omega-6 fatty acids because we need enough arachidonic acid to allow our body to convert into
signaling compounds as it needs them, then arachidonic acid fills a role similar to that of vitamins A and D. We require
several hundred micrograms per day of vitamin D and several milligrams per day of vitamin A. To put this in perspective,
we consume proteins, carbohydrates and fats in gram amounts. A microgram is one millionth of a gram and a milligram is
one thousandth of a gram. We should therefore expect the requirement for essential fatty acids to constitute an extremely
small percentage of our total energy intake.
Researchers who attempted to quantify the essential fatty acid requirement using purified fatty acids showed that
just over two percent of calories as linoleic acid was needed to prevent deficiency in growing rats while less than 0.7
percent of calories as arachidonic acid was needed. Lower amounts of arachidonic acid may have proven effective had
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the researchers tested them. The Burrs did not use this approach. They used purified fatty acids to prove the point that
the fatty acids themselves were curative, but used whole foods to quantify the requirement. “All workers,” they wrote,
“recognize the fact that the acids isolated by the bromination method may not have exactly the same structure that they
had in the natural oil.” The Burrs showed that the requirement was only 0.4 percent of calories when they used lard to
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cure the disease in growing rats and that the requirement was only 0.1 percent of calories when they used liver to cure it.
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Liver probably proved more effective than lard both because it is much richer in arachidonic acid and because it is rich in
vitamin B , which greatly enhances the conversion of linoleic acid to arachidonic acid.
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The essential fatty acid requirement seems to be similar in humans. Butter supplying 1.3 percent of calories as PUFA
prevented poor growth, scaly skin and increased susceptibility to infections in human infants consuming a formula made
partly from skim milk and mostly from corn syrup, but the investigators did not try using smaller amounts. The same
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authors reported that both 1.3 percent and 2.0 percent of calories as purified linoleic acid incorporated into a synthetic
fat molecule cured eczema in infants fed the same type of formula. The requirement for purified linoleic acid in human
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infants fed a diet composed mostly of refined sugar is thus similar to the requirement in young, growing rats fed a similarly
atrocious diet, which suggests that the essential fatty acid requirement in infants and growing children can be met by a diet
providing less than 0.5 percent of calories as PUFA from animal fat, and much less than this if the fat is provided by liver.
One naturally wonders what the essential fatty acid requirement might be in people who are not consuming most of
their calories as refined sucrose or corn syrup. In the 1960s, researchers compared the effect of starch-based and sucrose-
based diets on PUFA metabolism. Both diets were deficient in essential fatty acids. The starch-based diet contained only
0.003 percent more calories as linoleic acid than the sucrose-based diet, but the rats fed starch had 50 percent more
arachidonic acid and 80 percent more linoleic acid in their livers than the rats fed sucrose. Similarly, in essential fatty
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acid-deficient infants fed 80 percent corn oil, replacement of half the corn oil with hydrogenated coconut oil, which is
completely devoid of PUFAs, substantially improved their eczema. High-sucrose diets increase lipid peroxidation in rats,
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a process that causes the destruction of essential fatty acids. Reducing refined sugar in the diet is therefore likely to sharply
reduce the essential fatty acid requirement. A number of other factors may reduce this requirement as well, including
biotin, vitamin B , calcium, magnesium, avoidance of rancid vegetable oil, sufficient intake of protein and total energy, and
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a diet rich in fresh, whole foods abundant in natural antioxidants. 31
22 Wise Traditions FALL 2010