Taller people have a higher risk of developing cancer. The World Cancer Research Fund reports that there is strong evidence that taller people have a higher risk of developing cancer of the following parts of the body:

• pancreas
• Colon
• Uterus (endometrium)
• Ovary
• prostate
• kidney
• Skin (melanoma) and
• Breast (pre- and postmenopausal).

But why? Here you can find out what we know, don’t know and suspect.

A well-established pattern

The British Million Women Study found that for 15 of the 17 types of cancer examined, the risk of developing them increases with height.

Overall, each 10 centimetre increase in height increased the risk of cancer by around 16 per cent. A similar increase was seen in men.

Let’s put that into perspective. If about 45 out of 10,000 women of average height (about 5’5″) get cancer each year, then about 52 out of 10,000 women who are 5’9″ tall would get cancer. That’s only seven extra cases of cancer.

So it is actually a fairly small increase in risk.

Another study found that 22 of 23 cancers were more common in tall people than in short people.

Why?

The association between height and cancer risk is observed across all ethnicities and income levels and has also been examined in studies looking at genes that predict height.

These results suggest that there is a biological reason for the association between cancer and height.

Although the cause is not entirely clear, there are some compelling theories.

The first reason is that taller people have more cells. For example, a tall person is likely to have a longer colon with more cells and thus more entries into the colon cancer lottery than a shorter person.

Scientists believe that cancer is caused by an accumulation of genetic damage that can occur during cell division to form new cells.

The more often a cell divides, the more likely it is that genetic damage will occur and be passed on to the new cells.

The greater the damage, the more likely cancer will develop.

A person with more cells in their body will experience more cell division, potentially increasing the chance that one of those cells will develop cancer.

Some research supports the idea that tall people are more likely to develop cancer because they have more cells. This may explain to some extent why men are more likely to develop cancer than women (because they are, on average, taller than women).

However, it is not clear whether body size is related to the size of all organs (for example, do taller women have larger breasts or larger ovaries?).

One study attempted to find out. It found that in eight of the 15 cancers studied, organ mass explained the association between height and cancer, but in seven others, organ mass did not explain the association with height.

It should be noted that this study was quite limited in the amount of data available to it on organ mass.

Another theory suggests that there is a common factor that makes people taller while also increasing their risk of cancer.

One possibility is a hormone called insulin-like growth factor 1 (IGF-1). This hormone supports growth in children and also plays an important role in cell growth and division in adults.

This is an important function. Our body needs to produce new cells as old ones become damaged or age. Think of all the skin cells that come off when we use a good body scrub. These cells need to be replaced so that our skin doesn’t wear out.

However, you can have too much of a good thing. Some studies have shown that people with higher than average levels of IGF-1 have a higher risk of developing breast or prostate cancer.

However, this finding is not consistent for all types of cancer.

It is likely that both explanations (more cells and more IGF-1) play a role.

However, more research is needed to truly understand why tall people develop cancer and whether these findings can be used to prevent or even treat cancer.

I’m tall. What should I do?

What can you do if your height is more like LeBron James than Lionel Messi?

First, remember that height only slightly increases the risk of cancer.

Second, there are many things each of us can do to reduce our risk of cancer, and these things have a far greater impact on cancer risk than height.

We can take a closer look at our lifestyle. Try:

• eat healthily
• exercise regularly
• Maintain a healthy weight
• Be careful in the sun
• Limit alcohol consumption.

And most importantly: don’t smoke!

If we did all these things, we could significantly reduce the number of cancer cases.

You can also participate in cancer screening programs that help detect breast, cervical and colon cancer early so it can be treated successfully.

And finally, take heart. Research also shows that being taller can reduce your risk of heart attack or stroke.

This article is republished from The Conversation under a Creative Commons license. Read the original article.