Physical activity and cancer risk.

[pjoshea13]

A new UK study below [1].

"UK Biobank is a prospective population-based cohort study. 364,899 adults (51.6 % females, mean age 56.0 years) were included. The exposure variable was physical activity level derived from the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Participants were categorised at 'high' (≥1,500 MET-minutes/week), 'moderate' (≥600 MET-minutes/week) or 'low' levels of activity following standardised IPAQ-SF scoring guidance."

"Conclusions: Regular physical activity is significantly associated with reduced risk for lung, breast, hepatobiliary tract, colon and oropharyngeal cancers. Our findings highlight the importance of physical activity promotion, particularly high levels of physical activity, in cancer prevention."

So far, so good. However:

"Sensitivity analyses showed associations of higher physical activity with lower oesophageal and higher prostate cancer incidence."

Say it ain't so. & I was going to begin higher physical activity tomorrow. LOL

-Patrick

[1] pubmed.ncbi.nlm.nih.gov/326...

Cancer Epidemiol

. 2020 Jul 16;68:101780. doi: 10.1016/j.canep.2020.101780. Online ahead of print.

Physical activity and cancer risk: Findings from the UK Biobank, a large prospective cohort study

Jennifer M Murray 1 , Helen G Coleman 2 , Ruth F Hunter 3

Affiliations expand

PMID: 32683280 DOI: 10.1016/j.canep.2020.101780

Abstract

Objectives: This study aimed to investigate the association between physical activity and site-specific cancer incidence.

Methods: UK Biobank is a prospective population-based cohort study. 364,899 adults (51.6 % females, mean age 56.0 years) were included. The exposure variable was physical activity level derived from the International Physical Activity Questionnaire-Short Form (IPAQ-SF). Participants were categorised at 'high' (≥1,500 MET-minutes/week), 'moderate' (≥600 MET-minutes/week) or 'low' levels of activity following standardised IPAQ-SF scoring guidance. Primary outcome measures included incident cancers at 20 sites. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) showing relationships between physical activity and cancer.

Results: 21,816 incident cancers were identified. Significant associations were identified between high physical activity levels and lower risk of lung (HR 0.81, 95 % CI: 0.70, 0.94), breast (female only) (HR 0.85, 95 % CI: 0.77, 0.94), hepatobiliary tract (HR 0.72, 95 % CI: 0.53, 0.97), and colon (HR 0.86, 95 % CI: 0.74, 0.99) cancers compared to low physical activity levels. Moderate levels of physical activity were associated with significantly lower risk of oropharyngeal (HR 0.71, 95 % CI: 0.55, 0.93), and lung cancer (HR 0.86, 95 % CI: 0.74, 0.99) compared to low physical activity levels. Sensitivity analyses showed associations of higher physical activity with lower oesophageal and higher prostate cancer incidence.

Conclusions: Regular physical activity is significantly associated with reduced risk for lung, breast, hepatobiliary tract, colon and oropharyngeal cancers. Our findings highlight the importance of physical activity promotion, particularly high levels of physical activity, in cancer prevention.

Keywords: Cancer; Cohort; Physical activity; UK Biobank.

Copyright © 2020 Elsevier Ltd. All rights reserved.

[6357axbz]

1500 minutes/week!!!! That’s 25 hours! Who the hell works out that much other than professional athletes?

[pjoshea13 in reply to 6357axbz]

Not 1500 minutes but 1500 MET minutes. (New to me.) Can be done in under 5 hours.

"... an example:

Walk 2 days a week at 5 METS for 30 minutes per session = 2 x 5 x 30 = 300 MET-minutes

Bike 1 day a week at 7 METS for 20 minutes = 1 x 7 x 20 = 140 MET-minutes

Elliptical machine 2 days a week at 6 METS for 40 minutes = 2 x 6 x 40 = 480 MET-minutes

Total MET-minutes for the week = 300 + 140 + 480 = 920 MET-minutes"

cooperinstitute.org/2017/12...

-Patrick

[6357axbz in reply to pjoshea13]

What does MET stand for?

[monte1111 in reply to 6357axbz]

Sitting on your ass = 1 MET. If that's per hour, I'm getting a least 24 METS per day. Typing has to be worth something. Maybe I'll make it to 25 METS today.

[pjoshea13 in reply to monte1111]

Someone once told me that you burn twice the calories if you get out of your chair & move around. In that case, I told him, I shall sit here twice as long.

-Patrick

[Currumpaw in reply to monte1111]

Hey monte1111!

If sitting on your butt is 1 MET then laying down, an entire side of your body in contact with a surface, must be equal to what? How does one calculate that? --(chuckle!)

This and the fish oil study of 2013 should just be lumped together.

timotur probably nailed it--bicycles! About 20 years ago I read an article referencing studies about the dangers that a bicycle seat poses to a man, the nerve bundles and his prostate.

Currumpaw

[pjoshea13 in reply to Currumpaw]

The best thing that one can say about the bicycle? (from memory):

'With the invention of the bicycle, the village idiot began to disappear throughout Europe.'

No, I'm not suggesting that the village idiots were cycling into the sunset.

With access to a bicycle, a young man was no longer fated to breed with a first cousin.

-Patrick

[Currumpaw in reply to pjoshea13]

Hey pjoshea13!

An extra finger or toe here or there could be useful--yes? Extra finger for typing? For some of us--Yes!

Currumpaw

[monte1111 in reply to Currumpaw]

It's probably only half a MET. But if you're like me, it takes 10 METS to get up. I'm starting to understand why my stationary bicycle is stationary.

[Garp41]

Maybe higher PCa risk due to bike riding.....pressure?

[timotur in reply to Garp41]

Yes, there's studies linking cycling to both prostate and testicular cancer, abeit controversial.

bmccancer.biomedcentral.com...

texasoncology.com/media-cov...

[treedown in reply to timotur]

The second one looks like something I have read before. Haven't read anything to put me off cycling but I have spent quite a bit of time tweaking my bike for fit . I just added saddles to 2 bikes I ride most to relieve pressure on rides longer than 35 miles.

[Hidden]

Sorry, time to start getting those METs going.

pubmed.ncbi.nlm.nih.gov/287...

mayoclinic.org/diseases-con...

[AnnieAppleseed]

I just don't see how that is possible. I just SEARCHED pubmed.gov and found this article, ending with "Patient summary: This review shows that exercise/physical activity interventions can improve quality of life, fatigue, fitness, and function for men with prostate cancer." pubmed.ncbi.nlm.nih.gov/266...

There are over 1400 papers on this topic and all that I have ever examined, show benefit for men with prostate cancer, indeed any and all cancers.

[pjoshea13 in reply to AnnieAppleseed]

Well, there was another study that reported higher risk:

"Higher levels of physical activity were associated with an increased risk of prostate cancer"

"We pooled data from 12 prospective US and European cohorts with self-reported physical activity (baseline, 1987-2004)."

"Association of Leisure-Time Physical Activity With Risk of 26 Types of Cancer in 1.44 Million Adults"

jamanetwork.com/journals/ja...

-Patrick

[AnnieAppleseed in reply to pjoshea13]

I cannot think of why this would be so, can you? It's a real puzzle as there is such a body of evidence favoring exercise at all stages, ages, etc.

[pjoshea13 in reply to AnnieAppleseed]

Years ago there was a large epidemiological study that assessed PCa risk based on BMI & also calorie intake.

The results were as you might expect - except for an anomaly. Men who were in the ideal BMI range but had unexplained high energy intake had excess risk for aggressive PCa,

To me, the finding made perfect sense - the men were burning up the calories with perhaps extreme exercise, and the cancer was being driven by the abundance of some nutient in the diet, perhaps because of elevated IGF-I.

I think that IGF-I can be controlled by restricting protein intake. For someone who runs a half-marathon every week, can that be done safely? A vegan diet might offer better control, since one can readily restrict an essential amino acid.

The only thing I can think of.

Best, -Patrick

[AnnieAppleseed in reply to pjoshea13]

Thanks Patrick. We all find cancer confusing. I've been in this world of it for 27 years and I still don't grasp anywhere near as much as I wish to. Be well.

[Currumpaw in reply to pjoshea13]

Hey pjoshea13!

Nice observation! Ruth Heidrich! Vegan! An Ironman at her age!

_________________________________________________________________________________________

Ruth Heidrich: The 81-Year-Old Triathlete On Going Vegan ...

renaissancehumans.com/ruth-...

__________________________________________________________________________________________

Currumpaw

[pwallace in reply to AnnieAppleseed]

wow, ann! so surreal to see your response here! i was just reading about your cancer journey on another site (a family member forwarded us the post). what an inspiration! thanks for your ongoing contribution to the field.

[AnnieAppleseed in reply to pwallace]

I am glad if any part of my story or work was helpful. Our website is being redone, should be up within the next week. annieappleseedproject.org

[treedown]

In a book I recently read prostate cancer is noted as requiring a higher met load then other cancers. Based on last week I calculated 176 Mets biking and 28 Mets walking I guess I am at higher risk forPC, oh wait....... Anyway not planning on making any changes. Also based on my calculation to hit 1500 Mets (not sure what MET-minutes are but I am by no means a educated on this) would be 62 hrs on the bike approx.

[LearnAll in reply to treedown]

My take on excessive biking is that it creates continuous friction in area where prostate gland is. This may have something to do with it.

[treedown in reply to LearnAll]

I agree it might but only if your doing it wrong IMO. I am not seeing friction wear on my bike shorts where the prostate is. Unless your referring to some kind of internal friction. I could speculate heat or pressure as well but none of that changes my mind. The benefits outweigh any speculated risks.

[PhilipSZacarias]

There is an association with prostate cancer and exercise. It is an association no claims of statistical significance were made. Phil

[Graham49]

Patrick

They say "sensitive analyses showed" but don't give the statistics for prostate cancer, perhaps the increase in cancer was not statistically significant.

If it was statistically significant could it be that a high level of exercise is good for survival after getting cancer but leads to a higher risk in getting the cancer?

Why only prostate cancer higher risk? I wonder if there were systematic differences in the diet between the high and low exercise groups, particularly affecting prostate cancer.

Graham

[pjoshea13 in reply to Graham49]

PCa is different in a fundamental way. Why is it that established type 2 diabetics have more cancer of every type - except PCa, where they have less? Could it be because a burn out of insulin-secreting cells is protective? & as I mentioned to Annie, the IGF-axis might be implicated (insulin-like growth factor.) Very well documented in the literature. & insulin itself can promote cancer.

It may be prudent to avoid extreme exercise that significantly increases energy intake. Alternatively, limit protein intake so as to control IGF-I.

-Patrick

[LearnAll]

Glad you posted this study. Thanks. This type of findings may help SOC "tunnel vision" fellows out of their tunnel vision.

A study done in Poland about metastatic prostate cancer and overall survival reached similar conclusion.

Patients were divided into two groups..first..who will not play soccer and second.ones who will play soccer 45 minutes each day. It was found that length of survival was significantly

more in group which played soccer daily for 45 minutes.

[fluffyfur]

No idea. My husband is very thin, super active, has a BMI of 22 and still has prostate cancer. He takes supplements, or took them until I had him throw them all in the trash. And no he doesn't bike ride.

[monte1111]

My mother lived to be 88. I never seen her exercise in my whole life. And she never got prostate cancer.

[pjoshea13 in reply to monte1111]

& yet, although rare, cancer of the female prostate (Skene's gland) does occur [1].

& I was only reading a few days ago that the ejaculate from the gland contains PSA [2]:

"The fluid also contains prostate specific antigen (PSA) and could have antibacterial properties that serve to protect the urethra."

-Patrick

[1] pubmed.ncbi.nlm.nih.gov/325...

[2] x-mol.com/paper/12846305965...

[monte1111]

Wow. You never cease to amaze me Sir.