"The Carcinogen Glycidol in Cooking Oils"
“The main purpose of frying is to produce
foods with good consumer acceptability.
However, not all acceptable foods are safe.”
Food chemists have been keenly interested in the
newly discovered toxic compounds produced by frying.
We’ve been refining vegetables oils for more than a century,
but only recently have we discovered that this can produce
concerning compounds such as 3-MCPD, and even worse, glycidol.
I talked previously about 3-MCPD.
It’s considered a nongenotoxic carcinogen with a tolerable
daily intake, whereas glycidol is a known genotoxic carcinogen,
meaning it can cause cancer by directly damaging our DNA.
If a compound is not directly DNA-damaging, it is assumed
that it acts through a mechanism which exhibits a threshold,
a so-called no-effect level may exist,
a level below which the compound may not be harmful.
But if a compound does damage DNA, historically a
non-threshold mechanism is assumed and no ‘safe level of intake’
can be derived, because it may only take a single DNA mutation
to start the march towards cancer.
So, such substances are not permitted
to be added intentionally to foods.
For so-called unavoidable contaminants the ‘ALARA’ approach
is applied, meaning that the level should be as low as
reasonably achievable or as low as reasonably practicable.
Since that’s what glycidol appears to be,
we should try to avoid it as much as possible.
An excess lifetime cancer risk of 1 in 100,000 is often used
as a figure for “acceptable” risk in a population.
Based on lab animal data, this might be exceeded
if someone weighing about 150 pounds consumed
less than a microgram a day.
Thanks to the use of refined oils in so many food products, though
the average glycidol exposure may be more than 50 micrograms.
And in children, the level of intake may exceed
acceptable cancer risk by 200-fold.
So, do people who eat more fried food get more cancer?
There is said to be strong evidence that there may be a higher risk
of developing chronic disease among frequent consumers of fried foods,
but that’s talking largely about cardiovascular health.
For example, in a study of more than 100,000 women,
frequent consumption of fried foods, especially fried chicken
and fried fish, were associated with a higher risk of
all-cause mortality, meaning such consumers lived, on average,
significantly shorter lives. But that was largely due
to cardiovascular mortality, whereas fried food consumption
was not generally associated with dying from cancer.
In men, however, a larger intake of fried food was associated
with a 35 percent increased risk of prostate cancer.
“Therefore, a suggestion may be put forward that subjects
at increased risk of prostate cancer should as a
precaution limit their consumption of fried foods.”
These refined oils are also used in infant formulas,
which presents a problem for babies who aren’t breastfed.
The German Federal Institute for Risk Assessment
has come to the conclusion that infants who are fed exclusively
industrially prepared infant milk formula
would take in harmful levels of glycidol.
And they have comparable levels of glycidol contamination
in U.S. formulas as they do over in Europe.
Yet another reason that breast is absolutely best.
Meanwhile, there are calls on the manufacturers of these products
to do everything they can to reduce levels as far as possible.
But evidently, the industry has yet to find a way
to refine vegetable oils without creating these kinds
of by-products “while at the same time maintaining the quality.”
It was therefore concluded that there are no easy solutions
to this problem, but I disagree.
We can choose to avoid the use of oils and fried foods.