Fats & Protein vs. Carbohydrates (Part 2)

[Guest guest]

THE OILING OF AMERICA (part 2)

Dr. Frederick Stare, head of Harvard University's Nutrition

Department, encouraged the consumption of corn oil—up to one cup

a day—in his syndicated column. In a promotional piece

specifically for Procter and Gamble's Puritan oil, he cited two

experiments and one clinical trial as showing that high blood

cholesterol is associated with CHD. However, both experiments had

nothing to do with CHD, and the clinical trial did not find that

reducing blood cholesterol had any effect on CHD events. Later, Dr.

Castelli, Director of the Framingham Study was one of

several specialists to endorse Puritan. Dr. Gotto, Jr.,

former AHA president, sent a letter promoting Puritan Oil to

practicing physicians—printed on Baylor College of Medicine, The

De Bakey Heart Center letterhead.9 The irony of Gotto's letter is

that De Bakey, the famous heart surgeon, coauthored a 1964 study

involving 1700 patients which also showed no definite correlation

between serum cholesterol levels and the nature and extent of

coronary artery disease.10 In other words, those with low

cholesterol levels were just as likely to have blocked arteries as

those with high cholesterol levels. But while studies like De

Bakey's moldered in the basements of university libraries, the

vegetable oil campaign took on increased bravado and audacity.

The American Medical Association at first opposed the

commercialization of the lipid hypothesis and warned that " the

anti-fat, anti-cholesterol fad is not just foolish and futile. . .

it also carries some risk. " The American Heart Association,

however, was committed. In 1961 the AHA published its first dietary

guidelines aimed at the public. The authors, Irving Page, Ancel

Keys, Stamler and Frederick Stare, called for the

substitution of polyunsaturates for saturated fat, even though Keys,

Stare and Page had all previously noted in published papers that the

increase in CHD was paralleled by increasing consumption of

vegetable oils. In fact, in a 1956 paper, Keys had suggested that

the increasing use of hydrogenated vegetable oils might be the

underlying cause of the CHD epidemic.11

Stamler shows up again in 1966 as an author of Your Heart Has Nine

Lives, a little self-help book advocating the substitution of

vegetable oils for butter and other so-called " artery

clogging " saturated fats. The book was sponsored by makers of

Mazola Corn Oil and Mazola Margarine. Stamler did not believe that

lack of evidence should deter Americans from changing their eating

habits. The evidence, he stated, " . . was compelling enough to

call for altering some habits even before the final proof is nailed

down. . . the definitive proof that middle-aged men who reduce their

blood cholesterol will actually have far fewer heart attacks waits

upon diet studies now in progress. " His version of the Prudent

Diet called for substituting low-fat milk products such as skim milk

and low-fat cheeses for cream, butter and whole cheeses, reducing

egg consumption and cutting the fat off red meats. Heart disease, he

lectured, was a disease of rich countries, striking rich people who

ate rich food. . . including " hard " fats like butter.

It was in the same year, 1966, that the results of Dr. Jolliffe's

Anti-Coronary Club experiment were published in the Journal of the

American Medical Association.12 Those on the Prudent Diet of corn

oil, margarine, fish, chicken and cold cereal had an average serum

cholesterol of 220, compared to 250 in the meat-and-potatoes control

group. However, the study authors were obliged to note that there

were eight deaths from heart disease among Dr. Jolliffe's Prudent

Diet group, and none among those who ate meat three times a day. Dr.

Jolliffe was dead by this time. He succumbed in 1961 from a vascular

thrombosis, although the obituaries listed the cause of death as

complications from diabetes. The " compelling proof " that

Stamler and others were sure would vindicate wholesale tampering

with American eating habits had not yet been " nailed down. "

The problem, said the insiders promoting the lipid hypothesis, was

that the numbers involved in the Anti-Coronary Club experiment were

too small. Dr. Irving Page urged a National Diet-Heart Study

involving one million men, in which the results of the Prudent Diet

could be compared on a large scale with the those on a diet high in

meat and fat. With great media attention, the National Heart Lung

and Blood Institute organized the stocking of food warehouses in six

major cities, where men on the Prudent Diet could get tasty

polyunsaturated donuts and other fabricated food items free of

charge. But a pilot study involving 2,000 men resulted in exactly

the same number of deaths in both the Prudent Diet and the control

group. A brief report in Circulation, March 1968, stated that the

study was a milestone " in mass environmental experimentation "

that would have " an important effect on the food industry and the

attitude of the public toward its eating habits. " But the million-

man Diet Heart Study was abandoned in utter silence " for reasons

of cost. " Its chairman, Dr. Irving Page, died of a heart attack.

HYDROGENATION AND TRANS FATS

Most animal fats—like butter, lard and tallow—have a large

proportion of saturated fatty acids. Saturated fats are straight

chains of carbon and hydrogen that pack together easily so that they

are relatively solid at room temperature. Oils from seeds are

composed mostly of polyunsaturated fatty acids. These molecules have

kinks in them at the point of the unsaturated double bonds. They do

not pack together easily and therefore tend to be liquid at room

temperature. Judging from both food data and turn-of-the-century

cookbooks, the American diet in 1900 was a rich one—with at least

35 to 40 percent of calories coming from fats, mostly dairy fats in

the form of butter, cream, whole milk and eggs. Salad dressing

recipes usually called for egg yolks or cream; only occasionally for

olive oil. Lard or tallow served for frying; rich dishes like head

cheese and scrapple contributed additional saturated fats during an

era when cancer and heart disease were rare. Butter substitutes made

up only a small portion of the American diet, and these margarines

were blended from coconut oil, animal tallow and lard, all rich in

natural saturates.

The technology by which liquid vegetable oils could be hardened to

make margarine was first discovered by a French chemist named

Sabatier. He found that a nickel catalyst would cause the

hydrogenation—the addition of hydrogen to unsaturated bonds to

make them saturated—of ethylene gas to ethane. Subsequently the

British chemist Norman developed the first application of

hydrogenation to food oils and took out a patent. In 1909, Procter &

Gamble acquired the US rights to the British patent that made liquid

vegetable oils solid at room temperature. The process was used on

both cottonseed oil and lard to give " better physical

properties " —to create shortenings that did not melt as easily on

hot days.

The hydrogenation process transforms unsaturated oils into

straight " packable " molecules, by rearranging the hydrogen

atoms at the double bonds. In nature, most double bonds occur in the

cis configuration, that is with both hydrogen atoms on the same side

of the carbon chain at the point of the double bond. It is the cis

isomers of fatty acids that have a bend or kink at the double bond,

preventing them from packing together easily. Hydrogenation creates

trans double bonds by moving one hydrogen atom across to the other

side of the carbon chain at the point of the double bond. In effect,

the two hydrogen atoms then balance each other and the fatty acid

straightens, creating a packable " plastic " fat with a much

higher melting temperature. Although trans fatty acids are

technically unsaturated, they are configured in such a way that the

benefits of unsaturation are lost. The presence of several unpaired

electrons presented by contiguous hydrogen atoms in their cis form

allows many vital chemical reactions to occur at the site of the

double bond.

When one hydrogen atom is moved to the other side of the fatty acid

molecule during hydrogenation, the ability of living cells to make

reactions at the site is compromised or altogether lost. Trans fatty

acids are sufficiently similar to natural fats that the body readily

incorporates them into the cell membrane; once there their altered

chemical structure creates havoc with thousands of necessary

chemical reactions—everything from energy provision to

prostaglandin production. After the second world war,

" improvements " made it possible to plasticize highly

unsaturated oils from corn and soybeans. New catalysts allowed

processors to " selectively hydrogenate " the kinds of fatty

acids with three double bonds found in soy and canola oils.

Called " partial hydrogenation, " the new method allowed

processors to replace cottonseed oil with more unsaturated corn and

soy bean oils in margarines and shortenings. This spurred a meteoric

rise insoybean production, from virtually nothing in 1900 to 70

million tons in 1970, surpassing corn production. Today soy oil

dominates the market and is used in almost eighty percent of all

hydrogenated oils.

The particular mix of fatty acids in soy oil results in shortenings

containing about 40% trans fats, an increase of about 5% over

cottonseed oil, and 15% over corn oil. Canola oil, processed from a

hybrid form of rape seed, is particularly rich in fatty acids

containing three double bonds and the shortening can contain as much

as 50% trans fats. Trans fats of a particularly problematical form

are also formed during the deodorization of canola oil, although

they are not indicated on labels for the liquid oil.12a

Certain forms of trans fatty acids occur naturally in dairy fats.

Trans-vaccenic acid makes up about 4% of the fatty acids in butter.

It is an interim product which the ruminant animal then converts to

conjugated linoleic acid, a highly beneficial anti-carcinogenic

component of animal fat. Humans seem to utilize the small amounts of

trans-vaccenic acid in butter fat without ill effects.

But most of the trans isomers in modern hydrogenated fats are new to

the human physiology and by the early 1970's a number of

researchers had expressed concern about their presence in the

American diet, noting that their increasing use had paralleled the

increase in both heart disease and cancer. The unstated solution was

one that could be easily presented to the public: Eat natural,

traditional fats; avoid newfangled foods made from vegetable oils;

use butter, not margarine. But medical research and public

consciousness took a different tack, one that accelerated the

decline of traditional foods like meat, eggs and butter, and fueled

continued dramatic increases in vegetable oil consumption.