"How to Lower Heavy Metal Levels with Diet"
We’ve previously explored
the issue of lead contamination in
calcium supplements like bone meal,
but it wasn’t just bone meal.
Substantial quantities of lead
were found in other, more common,
over-the-counter supplements.
Still, testing revealed continued
public health concern over bone meal,
but thankfully it’s not as popular these days.
So, many of us are not likely
to get directly exposed to the lead
in bone meal any more –
but may get indirectly exposed
through the animals we eat.
In the U.S., five billion pounds
of meat and bone meal are produced
as slaughterhouse by-products every year.
What do we do with these millions
of tons every year?
We feed it back to farm animals,
particularly chickens.
Now, most of the lead in the bone meal
passes right through the animals
into their waste, but then we take
that waste (cow, pig, and chicken feces)
and feed it back to the animals again.
You guessed it!
So, you can see how the levels
of contaminants might buildup in their body.
I’ve talked previously about what that might mean for
making something like chicken soup,
but the original concern about
these kinds of feeding practices,
of feeding cows to cows, and pigs and chickens,
was the spread of prion diseases,
like mad cow disease,
but it’s not just prions that
this kind of recycling can magnify;
but other toxic substances including lead.
So, a more plant-based diet
may be able to lower lead exposure,
and an even more plant-based diet
could theoretically lower exposure even more,
but you’ve got to put it to the test.
But, should we expect to find a benefit?
Yes, lead is one of the toxins found in meat,
but half of our dietary exposure
probably comes from plant foods.
Dietary modeling studies in Europe
suggest that vegetarians would be
exposed to about the same amount
of lead compared to the general population,
with the exception of those
who eat a lot of wild game,
which can end up with a thousand times
more lead than most other foods.
In fact, a vegetarian diet may even be higher in lead.
But, it’s not what you eat;
it’s what you absorb.
As we learned from the cadmium story,
the uptake of toxic heavy metals
from animal food sources into the human
intestinal lining cells may be higher
than that from vegetable sources.
That’s how you have a vegetarian
with some of the lowest concentrations
of lead and cadmium in her blood,
despite higher concentrations in her diet.
But you don’t know, until you…
put it to the test.
There seemed to be a tendency towards
higher fecal elimination of lead
following a change to a vegetarian diet,
with nine subjects on average tripling
their elimination of lead,
three unaffected, and four dropping by about half.
But, the study only lasted a few months;
the difference wasn’t statistically significant.
So, let’s try a year.
A shift towards a diet characterized
by large amounts of raw vegetables,
fruits, and unrefined foods, whole grains,
with the exclusion of meat, poultry, fish, and eggs
(though it did include fermented dairy,
like a type of soured milk),
as well as cutting back on processed foods and junk.
They took clippings of hair
before and after the shift,
and got significant reductions in heavy metals,
including cutting their lead level
nearly in half.
Check this out: this is how much
mercury, cadmium, and lead they had
oozing from their body into their hair
when they started,
and within three months,
their toxic heavy metals
went down, and stayed down.
How do we know it wasn’t
just a coincidence?
Because they went back up
a few years later
after the study was over,
after they went back to
more of their regular diet,
and their mercury, cadmium,
and lead levels shot back up
to where they were before.
Same thing with a different group after two years.
The drop in mercury is easy to explain,
presumably due to the drastic drop
in fish consumption, and the drop
in alcoholic beverages may have
contributed to the drop in lead,
but it also could have been
a cadmium-like effect,
where the decrease in hair lead content
could be due to the dietary shift
resulting in less absorption of lead
into the body in the first place.