If the economy isn't grim enough for you, just
check out the February issue of the Journal of HortScience,
which contains a report on the sorry state of fruits and veggies.
Apparently produce not only tastes worse than it did in your
grandparents' days, it also contains fewer nutrients - at least
according to Donald R. Davis, a former research associate with
the Biochemical Institute at the University of Texas, Austin.
Davis claims the average vegetable found in today's supermarket
is anywhere from 5% to 40% lower in minerals (including magnesium,
iron, calcium and zinc) than those harvested just 50 years ago.
1. On the Difficulty of Comparing "Then" and "Now:"
Davis is quick to note that historical data can sometimes be
misleading, if not altogether inaccurate. Take early measurements
of iron in foods: because scientists failed to sufficiently
remove clinging soil, iron levels appeared unusually high in
certain vegetables like spinach, (which gave rise to the myth
that it contained exorbitant amounts of the mineral - a myth
further propagated by the popular cartoon character, Popeye).
Then again, good historical data provides the only real-world
evidence of changes in foods over time, and such data does exist
- one farm in Hertfordshire, England, for example, has archived
its wheat samples since 1843.
2. On the So-Called "Dilution Effect:" Today's vegetables
might be larger, but if you think that means they contain more
nutrients, you'd be wrong. Davis writes that jumbo-sized produce
contains more "dry
matter" than anything else, which dilutes mineral concentrations.
In other words, when it comes to growing food, less is more.
Scientific papers have cited one of the first reports of this
effect, a 1981 study by W.M. Jarrell and R.B. Beverly in Advances
in Agronomy, more than 180 times since its publication,
"suggesting that the effect is widely regarded as common knowledge."
Less studied, though, is the "genetic dillution effect," in
which selective
breeding to increase crop yield has led to declines in
protein, amino acids, and as many as six minerals in one study
of commercial broccoli grown in 1996 and '97 in South Carolina.
Because nearly 90% of dry matter is carbohydrates, "when breeders
select for high yield, they are, in effect, selecting mostly
for high carbohydrate with no assurance that dozens of other
nutrients and thousands of phytochemicals will all increase
in proportion to yield."
2. On the "Industrialization" of Agriculture: Thanks
to the growing rise of chemical
fertilizers and pesticides, modern crops are being harvested
faster than ever before. But quick and early harvests mean the
produce has less time to absorb nutrients either from synthesis
or the soil, and minerals like potassium (the "K" in N-P-K fertilizers)
often interfere with a plant's ability to take up nutrients.
Monoculture farming practices - another hallmark of the Big
Ag industry - have also led to soil-mineral depletion, which,
in turn, affects the nutrient content of crops.
The Lowdown:
If you're still not buying the whole "organic-is-better" argument,
this study might convince you otherwise. As Davis points out,
more than three billion people around the world suffer from
malnourishment and yet, ironically, efforts to increase food
production have actually produced food that is less nourishing.
Fruits seem to be less affected by genetic and environmental
dilution, but one can't help but wonder how nutritionally bankrupt
veggies can be avoided. Supplements may be the only solution,
but why should we subcribe to second class found sources for
vitamins at the expense of first class fruits and vegetables?
