The low incidence of large and small bowel cancer in India

is often attributed to natural antioxidants, such as curcumin in the diet,

the yellow pigment in the spice turmeric, which is used in curry powder.

However, it is imperative to recall that beneficial effects attributed to diets

are seldom reproduced by administration of a single ingredient in that diet.

For example, diets rich in beta-carotene lower the risk of tobacco-related cancers,

but the administration of beta-carotene pills does not.

That doesn't stop researchers from trying, though.

Back in 2001, in a last ditch attempt to save the lives of 15 patients

with advanced colorectal cancer that didn't respond

to any of the standard chemotherapy agents or radiation,

they started them on a turmeric extract.

It appeared to help stall the disease in a third of the patients, 5 out of 15,

suggesting turmeric extract may cause clinical benefit in at least some patients

with advanced refractory colorectal cancer.

Now, if we were talking about some new kind of chemo,

and it only helped one in three,

you'd have to weigh that against chemo side effects,

losing your hair, sloughing of your gut, intractable vomiting, maybe being bed-ridden.

So in a drug scenario, a one in three benefit

may not sound particularly appealing,

but when we're talking about a plant extract shown to be remarkably safe,

even if it just helped 1 in a 100, it would be worth considering.

With no serious downsides, a one in three benefit

for end-stage cancer is pretty exciting.

To see if colon cancer could be prevented, five years later,

researchers at Cleveland Clinic and Hopkins tested two phytochemicals,

curcumin (from turmeric) and quercitin (found in red onions and red wine),

in people with familial adenomatous polyposis.

Colon cancer forms from polyps,

and there's this disease that runs in families

in which you develop hundreds of polyps,

which will eventually turn into cancer

unless you have your colon prophylactically removed.

So they took five such patients who already had their colons removed,

but still either had their rectum or a little intestinal pouch,

which were still packed with polyps.

This is where they started out, between 5 and 45 polyps each,

and this is where they ended up after six months

of curcumin and quercitin supplements.

On average, they ended up with fewer than half the polyps,

and the ones that they had left, shrunk in half.

Here's a representative endoscopic photograph before-and-after.

Kind of now-you-see-it-now-you-don't.

But what about patient one?

Got rid of all their polyps by month three,

but then they seemed to come back.

So they asked them what's what,

and it turned out the patient stopped taking the supplements.

Darn it!

So they put them back on the phytonutrient supplements for another three months,

and the polyps came back down,

all with virtually no adverse events and no blood test abnormalities.

By studying people at high risk for colon cancer

there were able to show noticeable effects within just months.

But polyposis is a rare disease;

they were only able to recruit five people for the study.

Thankfully, smokers are a dime a dozen.

Another five years later, researchers put 44 smokers on turmeric/curcumin supplements alone,

for a month and measured changes in their colorectal aberrant crypt foci,

which may act like precursors to polyps,

which are the precursors to cancer.

And we can see just after one month there was a significant drop

in the number of these abnormal crypt foci

in the high dose supplement group

but no change in the low dose group, with no dose-limiting side effects,

although the stools in the participants did turn yellow.