Breast cancer risk for women under 40

A breast cancer diagnosis under 40 is rare.  Only 4% of breast cancer cases in the UK occur in women under 40. This percentage is the same for men also (CRUK).

If you’re under 40, what may increase your risk?

• Young women who get breast cancer are more likely than older women to carry a known genetic mutation associated with increased risk, such as a BRCA mutation; they are also more likely to have a family history of breast cancer.
• Having high breast density is another important risk factor.
• Starting periods before age 12, being tall, and having certain types of benign breast disease also increase risk.
• Taking the combined contraceptive pill slightly increases the risk.
• First pregnancy in those 30 years of age or younger reduces the long-term risk of breast cancer. However, pregnancy at any age increases short-term risk. Women whose first pregnancy occurs after the age of 35 have a long-term increased breast cancer risk.
• Being underweight may also slightly increase risk.
• Other factors that increase risk at any age include a previous diagnosis of breast cancer, alcohol consumption, lack of physical activity, and exposure to hazardous chemicals such as carcinogens or endocrine-disrupting chemicals such as bisphenols found in certain plastics, epoxy resins, and thermal ink.

Sadly, not all breast cancer cases are preventable, and women (and men too) will be diagnosed through no fault of their own But studies have shown that by making changes to your lifestyle you can reduce your chances of getting breast cancer significantly.

Tips to reduce your risk of breast cancer

• Establish healthy eating patterns, which include eating a high proportion and variety of fresh fruit and vegetables and limiting the amount of processed food you eat.
• Try to limit the length of time you use oral contraceptives
• Limit alcohol consumption, the less you drink the less your risk of breast cancer
• Exercise regularly; as a minimum follow WHO guidelines
• If you’re considering having children try to have them before you’re 30
• Try to breastfeed if possible
• Minimise use of cosmetics and personal care products, especially those that contain endocrine-disrupting chemicals

For more information on how you can reduce your risk see our Everyday Life iguide and Chemicals and Environment iguide. To get your personalised prevention plan take our quick quiz. For further details on breast cancer, risk factors see our Breast cancer risk factors brief.

Chip in to help prevent breast cancer in future generations

Now more than ever, we need your help. Together we can help those we love to lower their risk of developing breast cancer. If you’ve found the information on our website helpful, then please consider making a donation today. You can help get prevention tips and advice to the next person who needs help to lower their risk of developing breast cancer.  Thank you.