Obese women 40 per cent more likely to get cancer

Cancer Research UK

Obese women have around a 40 per cent greater risk of developing a weight-related cancer in their lifetime than women of a healthy weight, according to new figures* released by Cancer Research UK.

"Losing weight isn’t easy, but you don’t have to join a gym and run miles every day or give up your favourite food forever. Just making small changes that you can maintain in the long term can have a real impact." - Dr Julie Sharp

Obesity increases a woman’s risk of developing at least seven types of cancer – including bowel, post-menopausal breast, gallbladder, womb, kidney, pancreatic and oesophageal cancer.

The new statistics find that obese women have around a one in four risk of developing a cancer linked to weight in their lifetime.

In a group of 1,000 obese women, 274 will be diagnosed with a bodyweight-linked cancer in their lifetime, compared to 194 women diagnosed in a group of 1,000 healthy weight women.

Approximately a quarter of UK women are obese** which puts them at a greater risk of cancer. There are different ways that obesity could increase the risk of cancer, and one possibility is that it is linked to a fat cell’s production of hormones –especially oestrogen. This hormone is thought to fuel the development of cancer.

In the UK it is estimated that 18,000 people develop cancer as a result of being overweight or obese each year***.

Tracey Tanner, a mother of one and property manager, aged 35, from London, kick-started her healthy lifestyle after she finished treatment for Hodgkin’s lymphoma in 2011. Since then she has lost six stone. She said: "My cancer diagnosis was a massive wake up call for me. After cancer I admitted to myself that I was more than overweight, I was obese.

“I knew I had to do something about changing my lifestyle so I began eating more healthy and exercising – I felt better and better. I’ve made other healthy changes too, giving up fizzy drinks and junk food. I’ve slowly worked myself up to take part in Race for Life and am now in training for my first marathon, which will be a huge milestone for me.”

Dr Julie Sharp, head of health information at Cancer Research UK, said: “Losing weight isn’t easy, but you don’t have to join a gym and run miles every day or give up your favourite food forever. Just making small changes that you can maintain in the long term can have a real impact. To get started try getting off the bus a stop earlier and cutting down on fatty and sugary foods. Losing weight takes time so gradually build on these to achieve a healthier lifestyle that you can maintain. And find out about local services, which can provide help and support to make lifestyle changes over the long term.

“We know that our cancer risk depends on a combination of our genes, our environment and other aspects of our lives, many of which we can control – helping people understand how they can reduce their risk of developing cancer in the first place remains crucial in tackling the disease.

“Lifestyle changes – like not smoking, keeping a healthy weight, eating a healthy diet and cutting back on alcohol – are the big opportunities for us all to personally reduce our cancer risk. Making these changes is not a guarantee against cancer, but it stacks the odds in our favour.”

ENDS

For media enquiries contact the Cancer Research UK press office on 020 3469 6189 or, out of hours, on 07050 264 059.

Notes to Editor

There are filming opportunities available throughout the summer at Cancer Research UK’s Race for Life events. Cancer Research UK's Race for Life 5k, 10k or Pretty Muddy Race for Life events, which run across the UK this summer, are an ideal way for women to begin to increase their physical activity to help maintain a healthy weight. Race for Life events are accessible to all women, regardless of their age, shape or fitness level, so you can walk, jog or run – the most important thing is being there and as well as the health benefits, women can raise money to help us beat cancer sooner.

* Calculated by the Cancer Research UK Statistical Information Team, February 2015. Based on lifetime cancer risks for 2009-2011 in the UK, proportions of overweight and obese women aged 16 and over from 2011-2013 in the UK, and body-weight associated cancer risks from Parkin DM, Boyd L,  Cancers attributable to overweight and obesity in the UK in 2010. Br J Cancer 2011.

BMI ranges for bodyweight have been defined as 18.5-25 for healthy weight, 25-29 for overweight and 30 plus for obese.

Body-weight is a risk factor for oesophageal adenocarcinoma only which accounts for more than half of all oesophageal cancers.  Bodyweight is a risk factor for endometrial cancer which is around 9 in 10 of all uterine cancers. Lifetime risks have been calculated using oesophageal and uterine cancer respectively. 

Cancer type

Relative risk

Absolute lifetime risk (per 1,000 women)

 

Overweight

Obese

Cases in healthy weight women

Cases in overweight  women

Cases in obese women

Percentage change (%)

All body-weight linked cancers

n/a

n/a

194

229

274

41

Breast (post-menopausal)

1.12

1.25

99

111

124

25

Bowel

1.15

1.32

50

58

66

32

Pancreas

1.14

1.30

13

15

17

31

Oesophageal (adenocarcinoma)

1.55

2.40

6

9

14

133

Uterus (endometrium)

1.52

2.31

16

24

37

131

Kidney

1.31

1.72

9

12

16

78

Gallbladder

1.23

1.51

0.1

0.1

0.2

100

 

** http://www.cancerresearchuk.org/cancer-info/cancerstats/causes/overweight-obesity-statistics/#by

*** http://www.cancerresearchuk.org/cancer-info/cancerstats/causes/preventable/ based on Parkin DM, Boyd L. Cancers attributable to overweight and obesity in the UK in 2010. Br J Cancer 2011;105(S2):S34-S37.