Reduce your risk of developing breast cancer after the menopause by maintaining a healthy weight throughout your life
- The more weight you gain in your life, the higher your risk of developing breast cancer after the menopause
- By keeping to a healthy weight, you can reduce your risk of breast cancer after the menopause
How does my weight affect my risk of developing breast cancer?
Your risk of developing breast cancer increases if you are overweight or obese after the menopause. The menopause is when you stop having periods and are not able to get pregnant naturally.
In the UK the average age of the menopause is 51, but it can range from 45 to 55 years of age. Putting on weight throughout adulthood also increases your risk of developing breast cancer after the menopause.
The more weight you gain over the course of your adult life, the higher your risk. Being obese when diagnosed with breast cancer can increase the risk that your cancer will recur (come back after treatment). It can also reduce your chances of surviving the disease.
Research also suggests that being overweight or obese before the menopause slightly reduces your risk of developing breast cancer before the menopause, although these links are not as clear.
But it’s important to know that breast cancer risk increases with age, so the effect of breast cancer risk is most important after the menopause, which is when four out of five breast cancers occur. Keeping to a healthy weight throughout your life will reduce your risk of developing breast cancer at this time.
What is my BMI?
The most common way of assessing if you are a healthy weight is by working out your BMI (Body Mass Index). BMI is a measure that uses your height and weight to work out if your weight is healthy.
The table below shows the different ranges of BMI. BMI may not be an accurate way to assess weight for pregnant women or athletes.
You can calculate your BMI using the Healthy weight calculator from the NHS.
How much does my weight affect my risk?
The higher your BMI after the menopause, the higher your risk of breast cancer will be. We can show this in the graph below. This shows how many women out of 100 will probably develop breast cancer after the age of 50, depending on their BMI.
Graph showing the estimated number of women out of 100 who will probably develop breast cancer at age 50 or above
- In a group of 100 women with a BMI between 22.5 and 24.9 (within the healthy range), about nine will probably develop breast cancer at age 50 or above. Find out how age affects breast cancer risk
- But in a group of 100 women with a BMI of 30 or more (in the obese range), about 11 or 12 will probably develop breast cancer
- So, being obese causes about two or three extra women out of every 100 to develop breast cancer at age 50 or above
Your waist size can also be important to consider. For women, a waist circumference of up to 31.5 inches (80 cm) is considered healthy. A measurement above this is regarded as high. It is likely that carrying more fat around your waist (for example, having a high-risk waist size) slightly increases your risk of breast cancer. This may be true even if your BMI is within the healthy range. You can find out more about waist size from the NHS website.
So, the higher your BMI after the menopause, the higher your risk of developing breast cancer. By keeping to a healthy weight throughout your life, you can reduce this risk.
How can I keep my weight healthy?
You can keep to a healthy weight by:
- Eating a balanced diet rich in fruit and vegetables
- Eating less sugary or fatty processed foods
- Eating and drinking the right amount for you and consuming the right amount of calories. Find out more about calorie intake from the NHS website.
- Taking part in regular physical activity
We have more information and tips to keep your weight healthy in our blog - Making healthy food choices.
Taking part in regular physical activity is another way to reduce your risk of developing breast cancer. Learn more about the benefits of being more physically active and ideas to get you started.
If you are worried about your weight, we recommend that you speak to your doctor for advice on how to manage your weight and introduce good habits into your day-to-day life.
How do we calculate our data?
We base our calculations on evidence that we judge to be reliable and of most relevance to the UK population. We’d like to thank the Statistical Information Team at Cancer Research UK for providing us with baseline data (June 2017).
Note: Some figures have been rounded up for clarity.
Health Survey for England 2015: Adult overweight and obesity
Information last reviewed: November 2017
Next review due: November 2020
Breast Cancer Now's health information is covered by NHS England's Information Standard quality mark. Find out how this resource was developed.