Eating Vegetables Doesn’t Stop Cancer

http://well.blogs.nytimes.com/2010/04/08/eating-vegetables-doesnt-stop-cancer/

by tokenadult • 16 years ago

20 23 16 years ago

well.blogs.nytimes.com

tokenadult3• 16 years ago

The underlying research article is

"Fruit and Vegetable Intake and Overall Cancer Risk in the European Prospective Investigation Into Cancer and Nutrition (EPIC)" by Paolo Boffetta, Elisabeth Couto, Janine Wichmann, et al. Journal of the National Cancer Institute Advance Access published online on April 6, 2010 JNCI Journal of the National Cancer Institute, doi:10.1093/jnci/djq072

I remember years ago reading a statement by Jerry Pournelle in Byte Magazine that he thought people eating more fruits and vegetables could prevent more cases of cancer than all the activities of the United States Environmental Protection Agency combined, but perhaps we now have to reject that hypothesis.

nickpp2• 16 years ago

Lowers risk of heart disease or stroke instead. Sounds good to me!

ZeroGravitas• 16 years ago

It also lowers the chance of cancer, which you wouldn't guess from the headline:

"Eating more vegetables was associated with a small but statistically significant reduction in cancer risk"

It's a 4% reduction for 2 extra servings of veg, which they helpfully illustrated by saying if you had 10% chance of cancer without vegetables, eating them would mean you would then have a 9.6% chance. I'm guessing that was an attempt to downplay the significance. If they'd said for every 25 people who get cancer, one wouldn't then it might have seemed more like good news.

They also claim that number could be wrong and list various factors why the results could be skewed, but never explain why they think the number would only get worse, rather than better due to these confounding factors.

tokenadult3• 16 years ago

A good discussion of the different ways to report results of medical interventions (including changes in diet) can be found here:

http://www.skepticstoolbox.org/hall/

fhars• 16 years ago

But that means people eating more fruit and vegetables will actually increase the cancer rate in the society, as fewer people die before they develop cancer (which is an almost inevitable event in an ageing body). Of course, this is related to the effect that you can double the number of people that suffer from a aggressive form of cancer by finding a treatment that makes them live twice as long after diagnosis (if you count all current cases and not only all new cases). Statistics and epidemiology are, ahm, fun is not quite the right word.

tokenadult3• 16 years ago

Looking for the "hard endpoint" of reduced all-cause mortality is always an important issue when studying a lifestyle intervention or medical intervention.

youngian• 16 years ago

Thanks for finding the weirdly cynical lining to that cloud. You gave me a good laugh.

jjs• 16 years ago

Lowers risk of heart disease or stroke instead. Sounds good to me!

Not dying from X or Y increases your risk of dying from Z!

chasingsparks• 16 years ago

There is a related paper that I can't seem to find. The gist of which was:

Studies on the cancer-fighting prowess of many antioxidants often fail to mention that your body naturally synthesizes a lot of antioxidants (e.g. melatonin and glutathione). While ingested antioxidants are known to protect cells in vitro and theoretically do so in vivo, relative to naturally synthesized antioxidants they might account for little additional protection.

(If someone could find that paper, I'd appreciate it.)

grosenbush• 16 years ago

Provocative Headlines Sell Newspapers

teye• 16 years ago

For those who've read The China Study, note that this is about increasing consumption of vegetables, not decreasing consumption of anything else (including animal protein).

nova3• 16 years ago

Oh yes, the China Study.

http://www.cholesterol-and-health.com/China-Study.html

nickpp2• 16 years ago

FUD promoted by the well known Weston A Price foundation a very successful pusher of fat in our diets. While their motives aren't yet clear (diary&meat industry lobby) their methods are clear:

http://www.care2.com/causes/health-policy/blog/who-is-the-we...

nfnaaron2• 16 years ago

However, eating fruits and vegetables is still necessary for proper bodily function and general health. There is no better reason to eat fruits and vegetables than this. Cancer fighting is a sideshow, although an important one.

There is also the potential benefit that if you eat more fruits and vegetables then you're less hungry for junk food.

nova3• 16 years ago

> However, eating fruits and vegetables is still necessary for proper bodily function and general health.

Tell that to (ancient) Inuit.

nfnaaron2• 16 years ago

Hmmm ... interesting point.

Maybe it's: if you're not eating a total (ancient) Inuit diet, then fruits and vegetables combined with the relatively small amounts of protein and fats most other peoples eat is necessary ...

Hmmm

growingconcern• 16 years ago

Garbage study. They only looked at vegetables as a group - which probably included potatoes and the like (possibly in the form of french fries). They didn't look at particular subclasses of vegetables. And they also didn't look at raw versus cooked (where previous studies have found significant reduction for colo-rectal cancer rates for raw broccoli but no reduction for cooked broccoli).

mingdingo• 16 years ago

A very valid point. I don't think people make a serious effort to eat vegetables in a healthy way. Mashed potatoes? That's a vegetable serving. Broccoli that has been boiled for 20 minutes? Another vegetable serving. I bet most of these vegetable servings were in the form of some highly cooked and highly processed dish. How healthy is a salad if it's smothered in Ranch dressing? I could be wrong, but my observations strongly suggest that most people don't eat raw or lightly steamed vegetables

And you're absolutely right: some vegetables are a lot more beneficial than others. I bet most people eat the tastier vegetables (potatoes) while avoiding the healthier ones (cauliflower).

ig1• 16 years ago

Have you read the paper or are you just speculating ?

hugh3• 16 years ago

How does that make it a garbage study? Just because it doesn't divide up "vegetables" into tinier classes doesn't mean it didn't valuably disprove a perfectly well-formed and plausible hypothesis about vegetables as a group.

mhartl• 16 years ago

It's the "vegetables as a group" part. The "vegetable group" is ill-defined because some vegetables (such as potatoes and corn/maize) have nutritional profiles more akin to grains, with higher glycemic index and lower nutrient density. I'd be very surprised if eating lots of broccoli and cabbage doesn't lower cancer rates; lots of potatoes, not so much.

mark_l_watson• 16 years ago

I am not agreeing with the article: eating more vegetables should mean that you eat less meat which I would argue is more likely to be carcinogenic. Way off topic, but: before a very strenuous hike early this morning (last 5 pictures: http://picasaweb.google.com/mark.watson/SedonaHiking2010#) I 'carbed out' with miso soup loaded up with lots of 4 different kinds of veggies. I ate nothing else, and my energy level was great.

Eating Vegetables Doesn’t Stop Cancer

Related Stories