Small changes in daily habits may make a difference when it comes to breast cancer risk. Research has identified links between the disease and several lifestyle factors, including prolonged sitting, alcohol consumption, diet, sleep and body weight.
Here are eight habits worth reconsidering or adopting, along with the scientific findings behind them.
Habits to cut back on
1. Sitting for six to nine hours a day: Prolonged sitting after menopause is associated with a roughly 22% higher risk of breast cancer, while sitting for 10 hours or more is linked to a 28% higher risk compared with sitting for no more than five hours a day. Those were the findings of a 2025 American study involving more than 39,000 women.
What to do: Break up long periods of sitting throughout the day. Stand up regularly, walk around for a few minutes and try performing some everyday activities while standing.
2. Working consecutive night shifts: A Finnish study published in 2026 followed more than 42,000 women and found that among those aged 50 and older, working three or more consecutive night shifts was associated with a 64% higher risk of breast cancer. The researchers emphasized that the study was observational and therefore could not establish a cause-and-effect relationship.
What to do: Where possible, reduce the number of consecutive night shifts you work.
Even one alcoholic drink a day is associated with an increased risk of breast cancer
(Photo: Shutterstock)
3. Drinking alcohol: When it comes to breast cancer, even moderate drinking is not risk-free. A major review by the World Cancer Research Fund found that consuming just one alcoholic drink a day was associated with an increased risk of the disease. Alcohol is broken down in the body into several substances, including acetaldehyde, a known carcinogen, and may also affect estrogen levels.
What to do: Cut back on alcohol consumption.
4. Causing sharp blood sugar spikes: A 2025 meta-analysis covering 26 cohort studies and approximately 2.2 million women found that a diet with a high glycemic index was associated with a 5% higher risk of breast cancer. The glycemic index ranks carbohydrate-containing foods on a scale of 0 to 100 according to how quickly they raise blood glucose levels.
What to do: Reduce sugary drinks, sweets, pastries and refined grains. Choose fiber-rich carbohydrates that are digested more slowly and help moderate increases in blood sugar.
Habits worth maintaining
5. Losing excess weight and keeping it off: An analysis combining data from 10 cohort studies involving more than 180,000 women aged 50 and older found that women who were overweight, lost weight and maintained that loss had a lower risk of breast cancer. Among women who did not use hormone therapy after menopause, even a sustained loss of approximately 2 to 4.5 kilograms was associated with a reduced risk.
What to do: If you are overweight, aim for moderate, sustainable weight loss rather than an extreme, short-term diet.
Working three or more consecutive night shifts is associated with a higher risk of breast cancer among women aged 50 and older
(Photo: Shutterstock)
6. Eating colorful fruits and vegetables: Tomatoes, watermelon, pink grapefruit, guava and other brightly colored fruits and vegetables contain carotenoids, including lycopene. A meta-analysis found that women with the highest blood levels of lycopene had a 14% lower risk of breast cancer compared with those with the lowest levels. However, the researchers classified the certainty of the evidence as low.
What to do: Regularly include red fruits and vegetables, along with produce in a variety of other colors, in your diet.
7. Sleeping in the dark: A meta-analysis of 21 studies involving more than 734,000 participants found that greater exposure to light at night was associated with a 12% higher risk of breast cancer. One possible explanation is that nighttime light disrupts the body's internal biological clock and the production of melatonin, a hormone involved in regulating sleep.
What to do: Keep your bedroom as dark as possible, switch off unnecessary lights and avoid sleeping with the television or another screen turned on.
8. Eating plenty of fiber: Dietary fiber is best known for supporting digestion and promoting feelings of fullness, but research also suggests a connection to breast cancer risk. A 2025 meta-analysis found that higher fiber consumption was associated with a lower risk of breast cancer, with the association particularly pronounced among women who had not yet reached menopause.
What to do: Make legumes, oats, whole-grain bread, fiber-rich cereals, vegetables and fruits regular parts of your daily diet.
The author is a clinical dietitian with an M.Sc. degree and a master practitioner qualification in NLP for health and weight management.