Aside from family history, diet, and exposure to toxins, disrupting the circadian rhythm can also raise breast cancer risk.
Many breast cancer patients wonder why the disease sometimes occurs even if they maintain a healthy diet and have no family history of breast cancer. Dr. Zhang Jinjian, a leading breast cancer physician in Taiwan, shared that sleep habits can also affect breast cancer risk. He also discussed the more well-known factors that increase a woman’s risk.
Typical Breast Cancer Risks
One of the main factors that raises a woman’s risk of breast cancer is family history.
Actor Angelina Jolie is an example of someone who had a high risk of breast cancer due to a family history of cancer in multiple relatives. Her aunt had breast cancer, and her mother had died of ovarian cancer. Both had tested positive for BRCA1 gene mutation, which is linked to breast cancer. Jolie was found to have the same mutated gene; doctors told her her risk of developing breast cancer was close to 90 percent, and her chance of developing ovarian cancer was over 50 percent. Therefore, she decided to play it safe and had her breasts, ovaries, and fallopian tubes removed.
Zhang said mastectomies have come a long way in terms of preserving aesthetics. With today’s advanced reconstructive techniques, surgeons only need to make small incisions around the areola and under the armpit. This approach removes the breast tissue and allows for the placement of new implants. For those considering ovary removal who are concerned about the reduction of estrogen after removal, Zhang said women can take supplements or undergo hormone replacement therapy to maintain hormone balance.
- Early menstruation
- Late menopause
- Excessive hormone supplementation after menopause
- High-fat and high-calorie diets
- Not having children
- Endocrine disrupters
Zhang explained that menstruation stimulates progesterone and estrogen, stimulating the breast glands. Because these women will have more menstrual periods that activate their hormones, they end up with a comparatively higher risk of breast cancer.
For the same reason, excessive intake of female hormone supplements or consumption of high-fat and oily foods increases the risk of obesity and inflammation, thereby raising the risk of breast cancer.
Other risk factors are often related to lifestyle choices, like exposure to plasticizers or pesticide residues (endocrine disruptors), which can contribute to the risk of developing breast cancer. Common foods containing plasticizers include drinks bottled in plastics and ready-made ultra-processed foods. Improperly washed, conventionally grown vegetables and fruits can also retain pesticide residues.
Circadian Rhythm Disruption Can Increase Cancer Risk
Zhang said night owls should be particularly cautious, as disrupting the circadian rhythm can raise the risk of breast cancer. Women who work night shifts, such as health care workers, flight attendants, and 24-hour convenience store employees, have a higher chance of developing breast cancer than those with regular daytime schedules.
Related Stories
He explained that circadian rhythm describes how humans and animals naturally follow the cycles of day and night. The circadian rhythm emphasizes a crucial point: When it’s time to rest, both the body and brain need adequate downtime. While the brain is resting, it processes the information received during the day and clears out unnecessary waste, like taking out the trash. Without deep or sufficient sleep, people may experience difficulty focusing and mental fog the next day, affecting work and daily life.
When a person falls asleep, the body begins to release melatonin. Melatonin not only helps people enter a dormant state but also has a close relationship with the wellness of the immune system. People with poor sleep quality will have reduced immunity and be more likely to get sick. They will also be under more stress, increasing the risk of other cancers.
Depression Is a Potential Cancer Risk Factor
Poor sleep quality is often caused by anxiety or depression. Although depression is not the direct cause of breast cancer, Zhang believes that the stress and poor mood caused by depression will affect the endocrine system, weakening immunity and causing autonomic nervous system disorders, which could increase the risk of all sorts of gynecological diseases.
6 Tips for Improving Sleep Quality
Zhang suggested the following for improving sleep quality:
- The mattress and pillows should have a moderate level of firmness.
- Avoid the blue light from smartphones, computers, and TVs.
- Choose soft music before bed, avoiding exciting rhythms.
- Avoid late-night snacks.
- Refrain from intense exercise before bedtime; consider stretching gently or taking a warm bath to promote sleepiness.
- Avoid arguments before bed to prevent stress.
He also emphasized abiding by the body’s natural circadian rhythm, living in the present moment, taking it easy, learning to let go, and relaxing to avoid the threat of cancer.
