Margarine is Bad, Butter is Good
Subject: The Dinkum Oil (long) was The MEAT PIE THREAD
Date: 28 Sep 94 16:11:26 +1300
Organization: Victoria University of Wellington, NZ
> Noeline McCaughan wrote:
> >: of our good NZ Butter.*
> > Practically 100% saturated fat.
Now you've done it, Noeline. You hit the hot button! So here are more
facts than you really wanted to know about beautiful butter and mucky
The article below is provided by Sally Thomson of the Dairy Advisory
Bureau. Yes, I know that's open to the suspicion of being a biased
source, but read the excerpts from her article and judge the facts
The latest controversy has been fuelled by a Harvard University
report stating that a little known fat lurks in margarine and
other processed foods that could be responsible for 1000's of
heart attacks. Dr William Willett, a leading researcher says that
people who think it is healthier than butter are being grossly
(description of butter making process omitted for space reasons - BH)
Margarines in New Zealand are generally made from imported
vegetable oils, most commonly sunflower seed, soya bean, rapeseed
(canola) and palm oil. The oils are refined to remove impurities
before being hydrogenated. This process artifically "saturates",
or hardens oils into solid fat making them more suitable for food
Oil is hydrogenated by mixing it with fine particles of nickel
(a catalyst) heating it to 180 degrees celcius and pumping
hydrogen gas through it under high pressure. After filtering the
nickel out again, the oil is bleached and deodorised. As it cools
the hydrogenated oil turns into a waxy fat, which can be minced
into pellets for blending into any recipes needing solid `dry'
The hydrogenated `hardened' fat is then mixed with oil to form
a product with the desired texture. Antioxidants prevent the
polyunsaturated fatty acids in margarine from going rancid. The
type and amount of ingredients and additives that go into
margarine are controlled by the food regulations.
FAT IN SPREADS
Butter and margarine contain the same amount of fat, but differ
in fatty acid content.
Butter contains more saturated fat than margarine or vegetable
oils - it is 81 percent butterfat and 66 percent of the fatty
acids in butterfat are saturated fatty acids.
Table margarines contain less saturated fat and much more
polyunsaturated fatty acids.
This was good news for the margarine makers - until recently when
a number of studies cast doubt over the health benefits of
The new nutritional baddie, `trans fatty acids' has recently hit
the headlines. Trans fatty acids are found in margarines and
other processed foods such as cakes and biscuits that contain
vegetable oils which have been hydrogenated.
WHAT ARE TRANS FATTY ACIDS?
Trans fatty acids are unsaturated fats that are straight like a
saturated fatty acid, rather than bent at the unsaturated bond
like the cis form of mono and polyunsaturated fatty acids. Hence
trans and cis fatty acids act in the body like saturated fats and
in the case of CHD may be even worse.
Research shows that trans fatty acids may tend to act more like
other hardened fats (mostly saturated) in affecting cholesterol
levels. The replacement of naturally occurring fatty acids with
trans fatty acids can lower concentrations of high density
lipoprotein cholesterol (HDL) as well as increase low density
lipoprotein cholesterol (LDL). Trans fatty acids may also
adversely affect platelet function, consequently predisposing to
WHAT FOODS CONTAIN TRANS FATTY ACIDS?
Trans fatty acids occur naturally in the fats of ruminating
animals, so humans have been consuming small quantities of trans
fatty acids for centuries in foods such as beef, lamb, butter and
other dairy products.
Trans fatty acids are also formed by the industrial hydrogenation
or hardening of vegetables of vegetable oils used in the
manufacture of products such as margarines.
Based on US figures foods made with hardened vegetable-origin
fats will be higher in trans fatty acids. Examples of foods which
may have more than 30 percent of total fat as trans fatty acids
include water crackers, biscuits, muesli bars, confectionary bars
and foods made with vegetable shortening and some fried foods.
Currently there is little published information on the levels of
trans fatty acids in New Zealand foods. A recent study from the
University of Otago reports that the level of C18:1 trans fatty
acids in New Zealand margarines is approximately eight percent.
(Although there is unpublished data which indicates a higher
level - BH)
MARGARINE WORSE THAN BUTTER?
According to Dr William Willett from Harvard University, products
containing trans fatty acids, especially margarine have been
heavily promoted on the basis of health claims which have never
He also states that consumption of partially hydrogenated
vegetable fats has tracked closely in time with the epidemic of
CHD in the United States and elsewhere. And a more general
concern is that a major artificial element has been introduced
into the food supply without a full understanding of all its
metabolic and health implications.
Willett recently commented that trans fatty acids could be the
cause of 30,000 deaths from heart disease every year in the US.
He suggests that these fats in margarine may be more dangerous
than the saturated fats found in butter and he's calling on the
Food and Drug Administration to add them to food labels.
His research carried out in conjunction with a team at Harvard
Medical School looked at the dietary habits of 85,000 nurses in
Massachusetts over a period of eight years, and examined the role
of trans isomers of fatty acids on CHD risk.
In this large prospective cohort study a positive association was
observed between intake of trans fatty acids and risk of CHD. The
CHD risk of women in the highest quintile of trans fatty acid
intake was almost twice that of women in the lowest quintile of
intake. This relative risk remained irrespective of the intake
of multi-vitamins, saturated fats, monounsaturated fats, linoleic
acid, dietary cholesterol, carotene or fibre.
It is important to note however that in the 1980's when the study
was carried out much of the margarine eaten in the States was
stick margarine which is much `harder' than the polyunsaturated
margarine available in New Zealand. The trans fatty acid content
of stick margarine is very high, often over 30 percent.
The study also points the finger at processed foods containing
`bakers' fats' or vegetable shortenings found in biscuits, cakes
and pastries. "Many of these foods were touted as healthy because
they contained no cholesterol or saturated fat, but the trans
fats they contained were bad too," says Willett.
SEARCHING FOR TRANS ON LABELS
However finding out whether the margarine you eat is high in
trans fatty acids is not easy. Labels on foods do not spell out
how much trans fatty acid they contain. The only hint given is
usually a mention of `hydrogenated oils' and phrases like
`vegetable oil and fat'. Vegetable shortening' or `vegetable
margarine' are likely to contain hydrogenated oil.
Manufacturers in the UK have resisted moves to declare trans fats
and have lobbied to ensure that legislation from the European
Commission to standardise nutrition labelling from 1995 will
exclude the declaration of trans fat from the list of declared
nutrients. Proposals for implementing the Directive are currently
out for consultation.
The European Commission considers it is now time for
manufacturers to declare not only the amount of trans fats in
their products, but to drop the arbitrary division of fats into
saturated and unsaturated forms and instead focus on categorising
their fat into `cholesterol raising' and `cholesterol lowering
fats'. An article in The New England Journal of Medicine has
called for a similar labelling change in the US.
"Will people be shocked?- I suspect so," says Willett. "Many
people are trying to make good nutritional decisions for
themselves and their kids and being grossly misled."
Willett urged US companies to follow Europe's lead and make
margarine without trans fats, by altering the hydrogenation
The food industry and other scientists have blasted Willett's
report accusing him of overreacting. "We have to come back to the
big picture, reduce your total fat intake to 30 percent," they
The NZ National Heart Foundation's Scientific Committee Chairman,
Peter Leslie says the report needs to be treated with caution.
"Margarine has lower saturated fatty acids than butter, which is
the important point of difference. The trans fats aren't enough
to counter the benefits to some people of using margarine rather
He went on to say that there is as much fat in margarine as
butter, to suggest otherwise is misleading. "But its a different
kind of fat and less of a building block for cholesterol than
those in butter. Both should be used sparingly and properly."
The Harvard Nurses' study has received international coverage,
and reintroduced the butter/margarine debate to consumers, health
professionals and manufacturers. Its relevance to New Zealand
Meanwhile the edible oil industry is now researching ways of
reducing trans fatty acids. Non-hydrogenated margarines are on
the market in Canada however the low trans fatty acid content of
these products is offset by higher levels of saturated fat.
So please pass the...?
1. From Milk to Dairy Products. Oct 1990. New Zealand Dairy
2. Living Earth & Food Magazine/ Checkout:11-13. February 1994.
3. Consumer Magazine. Fat Battles. April 1994. Issue 325:12-14.
4. Menzing and Katan (1990). Effect of deitary trans fatty acids
on high density and low density lipoprotein cholesterol levels
in healthy subjects. New Eng J Medical 323, 439-45.
5. Zock PL et al (1992) Hydrogenation alternatives: effects of
trans fatty acids and stearic acid versus linoleic acid on serum
lipids and lipoproteins in humans, J Lipid. Res 33:399-410.
6. Litin and Sacks (1993) Trans fatty acid content of common
foods. New Eng J Medical 329,1969-70.
7. Willett WC, MD, DR PH & Albert Ascherio, MD Dr PH. Trans fatty
Acids:Are the Effects Only Marginal?
8. Willett WC et al.(1993) Intake of trans fatty acids and risk
of coronary heart disease among women. The Lancet. 341:581 -
9. Wahle KWJ, James WPT (1993) Eur J Clin Nutr 47;828-839.
10. Enig (1989) Fats and oils: understanding the functions and
properties of partially hydrogenated fats and oils and their
relationship to unhydrogenated fats and iols, University of
Maryland publication, Dept. of Chemistry and Biochemistry. June
If anyone wants the unexpurgated article, send me an e-mail
and I will arrange it.ÿ
Brian M Harmer I Personal mission statment:
Department of Communication Studies I
Victoria University of Wellington I to retain most of my marbles
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