Flaxseed & Flaxseed Oils for Omega-3 and EFAs
http://www.countcarbs.com/advice/LCT_flax_omega3_EFAs.htm
Flaxseed and flaxseed oil are currently recognized as appropriate
sources of omega-3 fatty acids by several US government agencies,
including USDA and NIH. These agencies have held conferences and
workshops on the importance of omega-3 fat , which have included
recommendations for consuming flaxseed.1
There are, however, present-day challengers on the Internet to the
use of flax as food. The Now Age Press website is a typical example.
Critics take issue with any statement made in recent years that refers
to flaxseed as having a history as a ˇ°stapleˇ± food in any culture. These
critics will admit only to the use of flaxseed as food in times of
famine. In addition to their challenge to the notion of the use of
flaxseed or flaxseed oil as food in antiquity, as well as to aspects of
safety related to the presence of lignans and various anti-nutrients
such as cyanogenic glycosides in flaxseed, the writers for these
websites make substantive mistakes about composition, stating, for
example, that hemp oil has levels of omega-3 fatty acids as high as flax
oil. Actually, flax oil contains about 60 percent of total fatty acids
as omega-3 fatty acids, compared to about 20 percent for hemp oil.2
When we search out historical documents written a century ago,
however, we are presented with another view. The 1911 edition of the
Encyclopaedia Britannica reported that ˇ°Linseed [flaxseed] formed an
article of food among the Greeks and Romans, and it is said that the
Abyssinians at the present day eat it roasted. The oil is to some extent
used as food in Russia and in parts of Poland and Hungary.ˇ±
The article also describes concern voiced over ˇ°. . . direct
adulterations. . . [by]. . . admixture of cheaper and inferior
oil-seeds. . . .ˇ± In 1864, a union of traders of linseed oil was formed
in England to prevent this adulteration by monitoring all imported
oil.3
The more recent Cambridge World History of Food records the use of
flaxseed oil for cooking in Russia in the 19th Century and the use of
seeds for making tea.4
A recent text on flaxseed, edited by researchers at the University of
Toronto, contains discussions of historical uses as a food, both
directly and indirectly. In the introduction, we learn that the edible
flaxseed was the one predominantly grown in India, that flaxseed is
consumed in the diet as oil in China, that it is consumed in Ethiopia in
a stew (wat), as a porridge (gufmo), and as a drink (chilka), and has
been part of the traditional foods in Egypt since the time of the
Pharaohs.5
In the US, the earliest record in Food and Drug Administration (FDA)
writings raises the question of GRAS status for flaxseed use in foods.
This appears in correspondence to the FDA in 1948 when the food industry
initiated an inquiry about the use of flax in cereal foods. The FDA
originally declined the GRAS status request because the use of flax, as
(or in) food prior to 1958, was in other countries and not in the US. In
addition, the FDA indicated concern about untreated flaxseed being a
source of toxic hydrocyanic acid and posted an import alert in 1978;
this decision was abandoned in 1982 when the import alert was canceled
and flaxseed was permitted in bread in levels of 10-12 percent. The
agency stated that there was no concern that there would be ˇ°. . . any
more exposure to hydrogen cyanide than from other foods such as lima
beans, fava beans, chickpeas, cassava, yams, cashews or almonds. . .
ˇ±6
Researchers from two universities evaluated flaxseed powder
consumption in women and reported that the lignans, which they
considered as protective against certain cancers, were normally
metabolized by the microflora in the gut. These researchers reported
that the possible cyanide exposure from 60 grams of raw flaxseed in
healthy individuals is not hazardous; further they indicated that raw
flaxseed is traditionally consumed in 10-gram amounts (approximately 1
tablespoon).7
So how much flaxseed, or flaxseed oil is appropriate and
unquestionably safe? The recommendation from the US government agencies
is usually 2 tablespoons of flaxseed per day to supply omega-3 fatty
acids for a 2000 kcal diet. (The flaxseed needs to be ground in order
for the proper digestion of the seeds to take place.) Two tablespoons of
flaxseed is about 20 grams of seed and since there is about 40 percent
oil in the seeds and about 50-60 percent omega-3 in the oil, 20 grams of
seed could provide about 8 grams of flaxseed oil and about 4 grams
alpha-linolenic acid, the basic omega-3 fatty acid. Four grams of
omega-3 fatty acids is about 36 calories, which is slightly more than
the usual recommendation of 1.5 percent of calories for a 2000 calorie
intake. The amount of flaxseed oil needed to provide this much omega-3
is about 1.5 to 2 tsp per day.8 If you are getting omega-3 fatty acids
from other sources in your diet, then the recommended amount of flaxseed
oil would be less.