Our researchers have found that height can affect cancer risk
Today, Cancer Research UK scientists have published research showing that taller people seem to be have a higher risk of cancer.
This may seem alarming, but tall people needn’t be too worried about these results.
The results only point to a small increase in risk, and most people aren’t so much taller than average that their height would have a strong effect on their chances of developing cancer.
Let’s have a look at what the researchers found.
Height and cancer in context
Researchers have been studying the links between height and breast cancer risk since the 1970s. This study is the latest in a long line of studies that have linked being taller to a higher risk of cancer, including testicular and ovarian cancer.
The latest results come from the Million Women Study, which involves so many people that the researchers were able to investigate the relationship between height and a range of different cancers including some less common types of cancer.
They found links between height and bowel, skin, breast, ovary, womb, kidney, and brain cancers, as well as leukaemia and non-Hodgkin’s lymphoma.
The Million Women Study has given us a huge amount of useful information about cancer risk in the past. Linking even small amounts of alcohol to cancer risk, providing groundbreaking results about the effects of hormone replacement therapy, and studying weight, reproductive history and diet, the results from the study have helped us understand more than ever before about what affects cancer risk.
Why might they be linked?
Although it seems that height and cancer risk are fairly clearly linked, with a 16 per cent higher relative risk for every extra 10cm (4 inches) of height, researchers are stumped about the reasons why this might be happening. But there are several theories.
It could be that taller people simply are made of more cells, so there’s more potential for one of them to go wrong and become cancerous.
Our genetic make-up also affects our adult height, and one recent study by Cancer Research UK scientists, looking into certain genetic changes in prostate cancer risk, found that one particular change was associated with being taller, and also linked to a higher risk of prostate cancer.
There are also things in early childhood that affect how tall we’ll be as adults. Diet, hormone levels, illnesses, and how affluent or deprived we are can all have an impact. And some of these things can be linked to cancer risk as well – so height could simply be a ‘marker’ for something else that’s causing the increase.
But at the moment, there’s little evidence to support any of these possible mechanisms.
It’s likely that future research, aimed at discovering more about how height and cancer risk are linked will give us some useful insights into how these cancers start and develop – insights that may lead to ways to improve treatment and care.
How big is the risk?
Let’s take breast cancer as an example. In this study, the researchers found that every extra 10cm (or 4 inches) of height was associated with a 17 per cent higher risk of the disease.
Drinking alcohol increases breast cancer risk: every extra unit per day increases the risk by 12 per cent (and a large glass of wine is about three units).
Comparing that to the effect of weight, the risk for women with the highest BMIs is 40 per cent higher than for the slimmest women.
Having children also has an effect. Women with no children have a 43 per cent higher risk of this disease than those who have had children.
So in comparison with these risks, the effect of height seems to be much smaller.
Controlling cancer risk
There are things we can’t control about cancer risk: getting older, the genes we were born with, and our height – to name a few.
But there’s also a lot we can do to reduce the risk of developing cancer in the first place.
Experts estimate that up to half of all cancers could be prevented by lifestyle changes. Being a non-smoker, cutting down on alcohol, keeping a healthy weight, being active, eating a healthy balanced diet and enjoying the sun safely can all reduce the risk of developing cancer.
And tall people, just as much as short, can benefit from living healthily – not just by lowering their risk of cancer, but of lots of other diseases too.
It’s also important for all of us to get to know our bodies, and what’s normal for us. That way, we’re more likely to notice if anything changes.
If you do notice any persistent or unusual changes, it’s a good idea to get it checked out by a doctor. It probably won’t be cancer, but if it is, getting it checked is the best thing you could have done – spotting cancer early means that treatment is more likely to be successful.
Jess
Comments
Jess Harris July 27, 2011
Thanks for your comments, everyone. To address a couple of the points:
Firstly, our researchers didn’t set out to do a study specifically on height. As we mentioned in the post, the results come from the Million Women Study, which was set up to investigate aspects of lifestyle, reproductive history, hormones and HRT, and their relation to cancer risk. It’s already provided lots of useful results in these areas – and the results on height were another analysis the researchers did on their existing data.
Clearly, people can’t change their height – but it is useful for researchers to look into possible associations like these because they can tell us more about the disease, how it starts and develops – which all adds up to improving our understanding of cancer and developing better ways of preventing, diagnosing and treating the disease in future.
On the point that we ‘promoted’ this research – it is part of our remit to communicate the results of the research that we fund, and in this case, the research was already being put in the public domain as a result of its publication in the Lancet. We felt it was worth press releasing the results to help make sure that the media covered its publication responsibly – which broadly they did.
We know that although there are lots of things we can’t change, there are also things we *can* do to reduce the risk of developing cancer. Results like these allow us to discuss these in public. And this helps us with one of our ambitious goals for 2020 – that more people will know how to reduce the risk of cancer. And knowing more about the links between body size and cancer risk doesn’t make those healthy living messages any less useful.
As far as Jonathan Bagley’s comments on passive smoking are concerned: one study (http://www.ncbi.nlm.nih.gov/pubmed/15741188) estimates that passive smoking may kill over 11,000 people every year in the UK from cancer, heart disease, strokes and other diseases. Reducing exposure to second hand smoke will help lower this figure. So we think that stopping smoking in public places is a great step forward for public health.
And Simon, we think it would be great to put in absolute risks. Unfortunately in this case it wasn’t possible, because the absolute risk we have is for the population as a whole, so it applies to everyone, not just the shortest people (Jonathan, that’s why applying a 17% increase in risk to the 12% lifetime risk for breast cancer doesn’t give a true picture). We’ve tried to give the risks some context by comparing the height-related risk with some other risks that people can understand a bit more easily.
Finally, there’s an excellent write-up on the NHS Choices website about this story which is well worth a read too: http://www.nhs.uk/news/2011/07July/Pages/tall-people-at-slightly-greater-risk-of-cancer.aspx (although they have put in some absolute risks in this post, the figures come straight from the study which only involved post-menopausal women, so aren’t applicable to the population as a whole.)
Michael De Podesta July 23, 2011
Chris G is right. Just like the information that using mobile phones and drinking coffee could ‘possibly’ cause cancer, this information is unhelpful. Actually being tall but in the normal range is a sign of general good health.
I know that cancer UK does much good work, but cancer is so scary for most people that it behoves Cancer UK to tread gently. This ‘tall’ news story promotes Cancer UK by making people associate thoughts of Cancer with every aspect of their lives. And that is pernicious.
Suppose Cancer UK set up a study to see if eating bananas caused cancer and concluded that they couldn’t detect any effect. Then the news headline would be “No evidence that eating bananas causes cancer” which would immediately associate bananas with cancer.
And by the way, even though bananas are radioactive, you really shouldn’t worry.
http://protonsforbreakfast.wordpress.com/2010/08/31/would-you-eat-a-radioactive-banana/
Chris G July 21, 2011
I saw the news this monring and thought, well I’m stuffed (given that I’m over 6 foot tall). Then I thougt about it harder. I don’t think that this kind of information is very helpful to the public at large – just makes us worried about something we can do nothing about!
Jonathan Bagley July 21, 2011
So a 1.17 relative risk which, as noted above, raises the absolute risk for breast cancer from 12% to 14%, is considered small by CRUK. Yet CRUK considers that a claimed (almost certainly the wrong order of magnitude) increase in absolute risk for lung cancer from 0.5% to 0.6% from 20 years of passive smoking for 4 hours a day justifies a ban on smoking in all non-residential buildings, including private smoking clubs and well-ventilated smoking rooms. You should decide whether you want to be a respected scientific body or a Fake Charity propaganda organisation. I stopped my donation two years ago.
Hippietwiggy July 21, 2011
Sorry but the information i have just heard on the news regarding taller women being at a higher risk of getting cancer is just ridiculous! The average women is 5ft 7in so there are less women over this height than below so of course the percentage would be higher. That’s just like saying that there is a higher increase for the risk for women with red hair than blonde or brown because there are fewer of this colouring! Ridiculous!
Simon K July 21, 2011
It’s a little disappointing that all of the figures given here are framed as relative rather than absolute risks.
Saying, for example, that “every extra 10cm of height was associated with a 17 per cent higher risk [of breast cancer]” is likely to be a very worrying message for taller women.
But framed differently, this could equally well have said that the absolute risk only rises from around 12% to around 14%.
Andrew Jack July 21, 2011
A recent post by the MacMillan organisation highlighted some disappointing news for UK residents.
Cancer is expected to jump from one in three to four in ten.
We have recently launched an app on the apple apps store called Healthy Living Tracker, this can help a person to spot for the sigs of cancer and other life shortening diseases.
Andy.
Dr Ellen CG Grant July 21, 2011
Once again the biggest cause of the cancer epidemic in women is omitted from the news. No mention at all that the large increases matching the increases in hormone use with occasional decreases when hormone use falls after warnings. How long is this cover up going to continue? The increases in breast cancer since 1962 seen at my website – http://www.harmfromhormones.co.uk in a lecture slide from the progesterone and breast cancer lecture. As most women now have taken progestins at some time or other, there are few never ever user for controls. This mean studies come out with misleading results. Progesterone use is much more carcinogenic than the body’s growth hormone.
protonsforbreakfast July 27, 2011
Jess:
I don’t know who you are but I guess you are a Cancer UK insider.
The words you are looking for are “Sorry, we got that press release wrong”. Admitting you got something wrong is how you learn not to do it next time.
Writing 500 words pretending you are right and this criticism is unjustified will not help you make a better decision next time.
Sincerely
Michael