Insulin-like growth factor (IGF-1) is a natural human growth hormone instrumental in normal growth during childhood, but in adulthood can promote abnormal growth—the proliferation, spread (metastasis), and invasion of cancer.
IGF-1 as One-Stop Cancer Shop
Why do centenarians escape cancer (people who live to be over 100 years old)?
As we get older, our risk of getting and dying from cancer grows year by year—but, once you hit about 85-90, your cancer risk starts to drop.
It kind of makes sense; I mean, if you didn’t get it by then, maybe you’re never going to get it. If you live that long, maybe it’s a sign that there’s something special about you. It seems that centenarians are endowed with a particular resistance to cancer. So, what’s their secret?
Well, every day, 50 billion of our cells die. And every day, 50 billion new ones are born. There’s a balance. Otherwise our body would atrophy, shrink, or get too big and crowded.
Now, sometimes we need to grow, like when we’re a baby, or that growth spurt around puberty. Our cells don’t get larger when we grow up; they get more numerous. A child’s hand may only be made up of about 50 billion cells, and may have to add a half trillion or so growing up.
Once we’ve already grown up, we don’t want a lot of extra cells hanging around. We still need our cells to grow and divide; out with the old, in with the new. We just don’t want to be making more cells than we’re putting out to pasture. When you’re a kid, extra growth can be good; when you’re an adult, extra growth can mean a tumor.
How do our cells know when to tip the balance in favor of more dividing and less dying, and when to come back into balance? A key signal is IGF-1, a growth hormone called insulin-like growth factor number 1. Levels goes up when you’re a kid, so you grow, and then come back down. Should your levels stay a bit too high as an adult, though, there’s this constant message to your cells grow, grow, grow; divide; don’t die; keep going; keep growing.
And so, not surprisingly, the more IGF-1 we have in your bloodstream, the higher our risk for cancer. More IGF-1, more prostate cancer; more IGF-1, more breast cancer.
Of course, it’s not the original tumor that tends to kill you; it’s the metastases. IGF-1 is a growth factor. It helps things grow, so it helps cancer cells break off from the main tumor, migrate into surrounding tissues, and invade the bloodstream.
What do you think helps breast cancer get into the bone? IGF-1. And the liver? IGF-1. Lung, brain, lymph nodes? IGF-1. It helps transform normal cells into cancer cells in the first place, then helps them survive, proliferate, self-renew, grow, migrate, invade, stabilize into new tumors, and even helps hook the blood supply up to the new tumor. IGF-1 is a growth hormone that makes things grow—that’s what it does. But too much growth, when we’re all grown up, can mean cancer.
Next, we’ll turn to how we can prevent all this.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Kerry Skinner.
Please consider volunteering to help out on the site.
- Yang SY, Miah A, Pabari A, Winslet M. Growth Factors and their receptors in cancer metastases. Front Biosci. 2011 Jan 1;16:531-8.
- Zhang Y, Ma B, Fan Q. Mechanisms of breast cancer bone metastasis. Cancer Lett. 2010 Jun 1;292(1):1-7.
- Kleinberg DL, Wood TL, Furth PA, Lee AV. Growth Hormone and Insulin-Like Growth Factor-I in the Transition from Normal Mammary Development to Preneoplastic Mammary Lesions. Endocr Rev. 2009 Feb;30(1):51-74.
- Salvioli S, Capri M, Bucci L, Lanni C, Racchi M, Uberti D, Memo M, Mari D, Govoni S, Franceschi C. Why do centenarians escape or postpone cancer? The role of IGF-1, inflammation and p53. Cancer Immunol Immunother. 2009 Dec;58(12):1909-17.
- Endogenous Hormones and Breast Cancer Collaborative Group, Key TJ, Appleby PN, Reeves GK, Roddam AW. Insulin-like growth factor 1 (IGF1), IGF binding protein 3 (IGFBP3), and breast cancer risk: pooled individual data analysis of 17 prospective studies. Lancet Oncol. 2010 Jun;11(6):530-42
- Rowlands MA, Gunnell D, Harris R, Vatten LJ, Holly JM, Martin RM. Circulating insulin-like growth factor peptides and prostate cancer risk: a systematic review and meta-analysis. Int J Cancer. 2009 May 15;124(10):2416-29.
- Gronek, Piotr ; Rychlewski, Tadeusz ; Słomski, Ryszard ; Stankiewicz, Krystyna ; Lehmann, Joanna. Insulin-like growth factor 1. Studies in Physical Culture and Tourism. 2005;12(1).
- Piantanelli L. Cancer and aging: from the kinetics of biological parameters to the kinetics of cancer incidence and mortality. Ann N Y Acad Sci. 1988;521:99-109.
- CDC Growth Charts. CDC. 2000.
Images thanks to Danielle Keller via Wikimedia Commons and SanShoot via flickr.
Why do centenarians escape cancer (people who live to be over 100 years old)?
As we get older, our risk of getting and dying from cancer grows year by year—but, once you hit about 85-90, your cancer risk starts to drop.
It kind of makes sense; I mean, if you didn’t get it by then, maybe you’re never going to get it. If you live that long, maybe it’s a sign that there’s something special about you. It seems that centenarians are endowed with a particular resistance to cancer. So, what’s their secret?
Well, every day, 50 billion of our cells die. And every day, 50 billion new ones are born. There’s a balance. Otherwise our body would atrophy, shrink, or get too big and crowded.
Now, sometimes we need to grow, like when we’re a baby, or that growth spurt around puberty. Our cells don’t get larger when we grow up; they get more numerous. A child’s hand may only be made up of about 50 billion cells, and may have to add a half trillion or so growing up.
Once we’ve already grown up, we don’t want a lot of extra cells hanging around. We still need our cells to grow and divide; out with the old, in with the new. We just don’t want to be making more cells than we’re putting out to pasture. When you’re a kid, extra growth can be good; when you’re an adult, extra growth can mean a tumor.
How do our cells know when to tip the balance in favor of more dividing and less dying, and when to come back into balance? A key signal is IGF-1, a growth hormone called insulin-like growth factor number 1. Levels goes up when you’re a kid, so you grow, and then come back down. Should your levels stay a bit too high as an adult, though, there’s this constant message to your cells grow, grow, grow; divide; don’t die; keep going; keep growing.
And so, not surprisingly, the more IGF-1 we have in your bloodstream, the higher our risk for cancer. More IGF-1, more prostate cancer; more IGF-1, more breast cancer.
Of course, it’s not the original tumor that tends to kill you; it’s the metastases. IGF-1 is a growth factor. It helps things grow, so it helps cancer cells break off from the main tumor, migrate into surrounding tissues, and invade the bloodstream.
What do you think helps breast cancer get into the bone? IGF-1. And the liver? IGF-1. Lung, brain, lymph nodes? IGF-1. It helps transform normal cells into cancer cells in the first place, then helps them survive, proliferate, self-renew, grow, migrate, invade, stabilize into new tumors, and even helps hook the blood supply up to the new tumor. IGF-1 is a growth hormone that makes things grow—that’s what it does. But too much growth, when we’re all grown up, can mean cancer.
Next, we’ll turn to how we can prevent all this.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Kerry Skinner.
Please consider volunteering to help out on the site.
- Yang SY, Miah A, Pabari A, Winslet M. Growth Factors and their receptors in cancer metastases. Front Biosci. 2011 Jan 1;16:531-8.
- Zhang Y, Ma B, Fan Q. Mechanisms of breast cancer bone metastasis. Cancer Lett. 2010 Jun 1;292(1):1-7.
- Kleinberg DL, Wood TL, Furth PA, Lee AV. Growth Hormone and Insulin-Like Growth Factor-I in the Transition from Normal Mammary Development to Preneoplastic Mammary Lesions. Endocr Rev. 2009 Feb;30(1):51-74.
- Salvioli S, Capri M, Bucci L, Lanni C, Racchi M, Uberti D, Memo M, Mari D, Govoni S, Franceschi C. Why do centenarians escape or postpone cancer? The role of IGF-1, inflammation and p53. Cancer Immunol Immunother. 2009 Dec;58(12):1909-17.
- Endogenous Hormones and Breast Cancer Collaborative Group, Key TJ, Appleby PN, Reeves GK, Roddam AW. Insulin-like growth factor 1 (IGF1), IGF binding protein 3 (IGFBP3), and breast cancer risk: pooled individual data analysis of 17 prospective studies. Lancet Oncol. 2010 Jun;11(6):530-42
- Rowlands MA, Gunnell D, Harris R, Vatten LJ, Holly JM, Martin RM. Circulating insulin-like growth factor peptides and prostate cancer risk: a systematic review and meta-analysis. Int J Cancer. 2009 May 15;124(10):2416-29.
- Gronek, Piotr ; Rychlewski, Tadeusz ; Słomski, Ryszard ; Stankiewicz, Krystyna ; Lehmann, Joanna. Insulin-like growth factor 1. Studies in Physical Culture and Tourism. 2005;12(1).
- Piantanelli L. Cancer and aging: from the kinetics of biological parameters to the kinetics of cancer incidence and mortality. Ann N Y Acad Sci. 1988;521:99-109.
- CDC Growth Charts. CDC. 2000.
Images thanks to Danielle Keller via Wikimedia Commons and SanShoot via flickr.
Republishing "IGF-1 as One-Stop Cancer Shop"
You may republish this material online or in print under our Creative Commons licence. You must attribute the article to NutritionFacts.org with a link back to our website in your republication.
If any changes are made to the original text or video, you must indicate, reasonably, what has changed about the article or video.
You may not use our material for commercial purposes.
You may not apply legal terms or technological measures that restrict others from doing anything permitted here.
If you have any questions, please Contact Us
IGF-1 as One-Stop Cancer Shop
LicenseCreative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Content URLDoctor's Note
This video seems like a departure from the last five videos, which describe an Ex Vivo Cancer Proliferation Bioassay, but those who’ve seen my full-length presentation, Uprooting the Leading Causes of Death, know that this all circles around in the end. I’ve touched on IGF-1 before, in Daily Hormonal Interference and Meat Hormones & Female Infertility, but soon you’ll know everything you wanted to about it (but may have been afraid to ask!).
For more context, be sure to check out my associated blog posts: Eating To Extend Our Lifespan; Stool Size and Breast Cancer Risk; Animal Protein and the Cancer Promoter IGF-1; Estrogenic Chemicals in Meat; and How Do Plant-Based Diets Fight Cancer?
If you haven't yet, you can subscribe to our free newsletter. With your subscription, you'll also get notifications for just-released blogs and videos. Check out our information page about our translated resources.