Give Medical Epidemiologists a Break

Whenever we start arguing over a healthy diet - and whether
science has anything credible to say on the subject - an image of the
witch in Disney's "Snow White" pops into my head.

She's holding out an apple. It's red, it's delicious, it's
reputedly good for you, except for maybe that eternal sleep thing. But
there's a very low probability of falling into a coma. In fact, science
would tell you zero probability since research has so far failed to
confirm that black magic can turn an apple into a potent sedative. So
go ahead, dearie, take a bite.

The whole question of what science can tell us about what to
swallow is, of course, more than fantasy. It's been getting an
intellectual workout this week, following a story in the most recent
New York Times Sunday Magazine, titled "Do We Really Know What's
Healthy?"

To greatly simplify the case made by author Gary Taubes: health
studies in large populations, partly observational studies, are
complicated and produce uncertain results. Such uncertainties in
epidemiology often lead to erroneous conclusions. Taubes provides
exhaustive - and sometimes damning - detail to support those
conclusions.

As we know, the result is a medically induced mental whiplash -
learning that alcohol, coffee, salt, fat, chocolate and their ilk are
good for us, no bad, good, no partly bad, no partly good, no wait, no,
maybe good. Taubes does a thorough, even exhaustive job, of exploring
the ways that science has led us into this state of confusion. The most
consistent complaint about the story, at least from those studying
science communication, is that it is overly negative and, even worse,
anti-science.

Myself, I don't think science reporting means science boosting.
The negativity doesn't bother me. I just wish he'd been negative in a
more interesting - or maybe a more comprehensive - way. I'm not
denying that epidemiology is an uncertain science. But what isn't? It's
not just that we don't understand a healthy lifestyle or say a healthy
diet. We don't even fully understand the individual health components
of that diet.

To return to my original example of the apple - beyond the fact
that witch-poisoned fruits are probably bad - we're not even sure how
to evaluate this single fruit. As it turns out, I'm a journalist-style
expert on apples because I just researched them for the magazine,
Science & Spirit (upcoming November/December issue). So I can tell you that
apples are loaded with chemical compounds that appear to protect
against cell damage and against diseases linked to such damage,
especially cancer.

But, as it turns out, all apples are not created equal. Research
by food scientists at Cornell University shows that apples growing in
the sunny crown of the tree contain much more of the good chemistry
than those hanging in the shade. Other studies show variation between
species. Golden Delicious apples are less potent than Red Delicious
(which I personally regret because I'm not a Red Delicious lover).
Fuji apples look promising on the chemical scale, McIntosh less so. But
those apple comparison studies have barely started - meaning that no
scientist can tell a consumer which apple in the fruit bowl contains
the best chemistry or whether it would be better to replace it entirely
with, say, some cranberries.

Further, scientists are also unsure which, if any, of the healthy
chemicals consumers actually absorb. This question of bioavailability
is another important unanswered question in the realm of food and
health. How much of the good stuff goes into my body? How much does
gets absorbed by Gary Taubes? Unknown. Do the chemicals in apples boost
the healthy chemistry of onions? Does it matter when you eat the apple,
early in the day, late at night? You guessed it, more unknowns. "Most
of research papers related to health benefits of apples are based on
laboratory [testtube] or animal model studies, therefore, we are not
completely sure about the REAL health benefit of apples on humans,"
says Chang Y. "Cy" Lee, chairman of the department of food science and
technology at Cornell.

And that's just using apples as an example - one could make the
same case for any fruit, vegetable, or other component of a healthy
diet. Adds Lee, "We need a long term human clinical study with those
special foods and bioactive compounds. We need to know the up- and
down-expression of genes due to special foods and compounds. Until that
time, scientists as well as industry that related to human health must
be cautious on claiming any specific foods and compounds on health
benefit."

So let's give the medical epidemiologists a break. But only a
short one. We need to encourage medical researchers to spend more time
exchanging information with food scientists, like Lee, and experts from
other down-in-the-field specialties. It's from that kind of
cross-disciplinary exchange of information - which occurs too rarely in
science - that the important questions are often answered. And I
suspect we'll need that and more if we really want to keep the witch
from the door.

Comments

[TonyOrlando]

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It has gotten to the point that I am afraid to ingest anything bought from the grocery store. It's a good comparison of the complete lack of accountability in our current government administration, and the food / Drug industry. The People always believe this rosy image that the public servents we select to serve us, do so. The FDA is a joke, and that is an understatement.

The food / drug industry will say what ever they want to get yuou to buy, period.

What I did weas hire a nutrionalist from a hospital. Had her meet me at the grocery store; and she brought clarity to all the lies, the spin.

Don't buy farm raised anything; look at the pale colors of the flesh. Buy darker fruits; just like the wild seafood, the more color, the more nutrition. No transfat, look carefully. Sugar causes diabeties. While caffine is such a strong drug, just up until several years ago, the Olympics tested for caffine. In fact caffine is as addictive as herion. It causes the body to max out on it's nervous system. So next time you are streed, ypour body has less room to accomadate.

I'm feed up. Hugo Chavez went into the People's grocery stores, and kicked out the corporate greed that cares nothing of it's fellow neighbors, only their bottom lines.

Genetic food by Monsanto; this is where it gets really scary. The hundreds of varieties of rice in India has gone to just a handful. Thank Monsanto, and they are located in Texas, just like the rest of the cobal..

[unitron]

The more important question is "Do We Really Know What's Healthful?".

The health of anything we ingest is pretty much a moot point by the time it's being digested.

[Purple Girl]

It amazes me when I hear scientific findings that support what my grandmother told me." Red wines good for your blood." We spend millions on questions that are really irrelevant. I'd rather have them test my food for safety. My weight can fluxuate 15-20- not because of what I'm eating, but how much and type of exercise I get on a daily basis. I eat what I want (usually in moderation) and try to keep my self moving. i think more health problems are related to toxins in our envirnoment and unsafe food supplies/ handling.
The apple's not killing you and neither will that peice of chocolate (unless your diabetic)

[NickHP]

Good on you. The precision and clarity of your explanation is wonderful. Quite different from most of the bogus articles I've seen and commented on elsewhere. Especially a bad one done by a homeopathic 'doctor' advocating 'common sense foods as medicine'. Whatever homeopaths are.

[Newfycrat]

You forgot to mention that an apple a day really does keep the doctor away, one study in England found that people who ate an apple a day had less lung problems (like bronchitis) then those who only took vitamin C or who made no difference in their diet.
What is interesting to me is that many of the wild versions of our foods are higher in most antioxidants, flavonoids and all the rest then our current commercial foods. Although the individual yields would be smaller (ie a smaller apple) the nutrition might be more dense. Also, without looking up the specific numbers, we as humans used to eat hundreds of different types of vegetables and fruits compared to only relatively few now. So not only are commercial foods giving us less nutrition, a smaller variety is also not helping.
I do not believe science will be able to understand the relationship of nutrition to our body in my lifetime. The body is too complex and the interactions are too complicated and impossible to measure accurately. And nutritional science is as or more biased then other sciences.
But I will say that it was the epidemiological studies of hunter and gatherer societies that really flipped my brain about human nutrition -this after a major revelation about the best way to feed dogs. There is nothing like being on a message board of a bunch of people with unhealthy dogs eating kibble having their dogs health turned around (in incredible ways) by eating a species appropriate diet (bones and raw foods) to make you realize just how important (proper evolutionary) nutrition is to your immediate and long term health.

[Danny]

We need more research into the mysteries of food science. But will the agrobusiness interests get in the way? Probably.
After all they are pushing genetically modified crops. Why would they give a sh*t if it's good for us even if not,as long as there's money to be made. Indian farmers are committing suicide by the thousands because of what GMOs are doing to them.