The facts about… obesity and womb (endometrial) cancer

Cancer is no longer something we’re afraid to talk about. Breakthroughs in treatment and increased awareness mean that – thankfully – breast cancer is a fairly common topic of conversation.

And while that’s great progress, it’s important it doesn’t stop there. Discussions about gynaecological cancers still take place behind closed doors and are often swept under the carpet. This is affecting women’s health adversely and we need to stop being afraid to discuss them openly.

Womb cancer (sometimes known as endometrial cancer) is the fourth most common cancer in women and the most common gynaecological cancer. There are 9,300 new cases of endometrial cancer – which affects the lining of the womb – in the UK every year, and of these there are 2,100 deaths. The incidence has doubled since mid-nineties. An alarmingly high number for a disease which doesn’t often make the headlines.

Research has proven there is a direct link between obesity and endometrial cancer, and one way of tackling the rising numbers of cases of this cancer is to educate women of the importance of keeping to a healthy weight.

That can often be easier said than done. I know from personal experience that it can be very difficult to get motivated and shed the pounds. And it’s not helped by the media: we are fed a confusing diet of images of super-thin models alongside articles about being proud of who we are and not letting our shape or size affect us.

So let’s be clear. I’m not talking here about shape or size or looks or body confidence. I’m talking about the simple science of trying to keep to a healthy body mass index (BMI) for your age and height in order to prevent the likelihood of diseases such as endometrial cancer, as well as others including diabetes.

We should be thinking of obesity as addiction to food the same way as some people are addicted to smoking. We need the same strong will and determination that ex-smokers have.

What is a healthy BMI?

The World Health Organisation (WHO) defines overweight as BMI greater than or equal to 25, and obesity as a BMI greater than or equal to 30. A BMI over 40 is classed as morbid obesity.

Your BMI is calculated as your mass per unit of surface area. If that sounds a bit baffling, there are plenty of online calculators you can use to work out your own BMI.

What are the symptoms of endometrial cancer?

Signs and symptoms can include:

  • Vaginal bleeding after menopause
  • Bleeding between periods
  • An abnormal, watery or blood-tinged discharge from your vagina
  • Pelvic pain

If you’re worried about any of these symptoms, it’s always a good idea to see your GP to get yourself checked out.

Why does obesity contribute to this type of cancer?

Oestrogen is the female hormone that builds the endometrium (lining of the womb). This is followed by progesterone putting a limit on building more endometrium, and preparing it to receive the fertilised egg for pregnancy.

Excess free oestrogen causes continuous building of the endometrium, and this may lead to cancer. Fat contributes to this process by increasing the level of oestrogen in the following way:

  • Fat cells can convert male hormones (androgen and testosterone) in the body (women also have some male hormones) to variants of oestrogen.
  • Obesity also increases the resistance to insulin, which means a high level of insulin but the tissue is not utilising it. Then, through a series of changes in the liver, excess insulin means there is excess free oestrogen.

Therefore, obesity increases the level of oestrogen in the body though more than one route and eventually increases the build up of endometrium – and as a consequence development of cancer.

While this is well known in the medical community, it is not necessarily widely known to the general population – which is why these are important conversations to have.

Can losing weight still help after a woman has been diagnosed? 

Yes, absolutely. Residual cancer cells may still be there in the blood or tissue but it is not always possible to detect them. Getting rid of extra fat will stop further stimulation of these cells. It can also reduce the risk of post-operative complications if you need surgery.

It isn’t easy to face up to the possibility that you might be overweight, or that this may cause medical issues further down the line. But it’s important to be realistic and arm yourself with the facts so you can make informed decisions.

Gynaecological cancers still seem to be the last word in taboo subjects. By bringing them into the forefront of conversations and not being afraid to address the issues surrounding them, we can reduce their prevalence and ultimately save lives.

Suha Deen

About Suha Deen

I'm a consultant/visiting professor in gynaecological pathology. I'm passionate about improving women’s health and keen to give back to women what I have learnt throughout my career, of what is well-known but not widely known.

  • Imogen Jamieson

    This is a really interesting read Suha. You are right, most people talk openly about breast cancer – which is great – but anything gynay related is usually cloaked in embarrassment and awkwardness and women hesitate to seek advice. An additional worry however, is that our GPs seem so over stretched these days that sometimes they are too busy to listen to a woman’s concerns – after she has plucked up the courage to go to see them in the first place – so what would be really useful is perhaps some thoughts on how to best approach these ‘difficult’ subjects when you go to the doctor so you can be sure they really ‘hear’ you….. I don’t know what others think

    • Suha Deen

      Thanks Imogen for the your note which is spot on! that is why cases sometimes get missed. Being young and healthy may work against you and the doctors may think, probably not serious!
      I will try to approach your question in the next article.