Better sleep, less cancer risk: The power of nightly rest

Quality sleep isn't just a nightly recharge—it's a proven way to lower your cancer risk. People who get enough restful sleep are much less likely to develop cancer, while those with poor or disrupted sleep face higher risks. Making sleep a priority is one of the simplest steps you can take to protect your long-term health.

In our fast-paced world, sleep is often sacrificed for productivity or screen time. But new research reveals that quality sleep is far more than a luxury—it's a powerful ally in cancer prevention.

Leading health authorities have confirmed the link between sleep and cancer risk. The World Health Organization's International Agency for Research on Cancer now classifies shift work with circadian disruption as a probable carcinogen, highlighting how seriously experts take this connection. The English Longitudinal Study of Ageing, which followed over 10,000 people for eight years, found that poor sleep quality increased cancer risk by 59%.

Poor Sleep Surge Cancer risks

Cancerworld data provides further evidence for the sleep-cancer relationship across multiple cancer types. Colorectal cancer risk rises by more than 50% among people with sleep disorders—sleep apnea alone increases risk by 76%, while insomnia boosts it by 54%. For women, short sleep duration is linked to nearly five times the risk of breast cancer compared to those who get enough sleep.

A 2023 study led by Dr. Deng Ning, involving nearly 15,000 participants, found that people sleeping less than six hours per night had a 41% higher risk of cancer than those sleeping 6 to 8 hours. If total sleep was less than seven hours, the risk jumped to 69%.

On the flip side, healthy sleep patterns can be powerfully protective. The UK Biobank study, analyzing data from 380,042 participants, showed that people with good sleep and lifestyle habits had a 28% lower overall cancer risk. For specific cancers, the benefits were even more striking: a 78% lower risk for lung cancer, 47% for liver cancer, and 39% for bladder cancer. 

Dr. David Gozal, chairman of pediatrics at the University of Chicago Comer Children's Hospital, put it simply: "This study offers biological plausibility to the epidemiological associations between perturbed sleep and cancer outcomes. The take-home message is to take care of your sleep quality and quantity like you take care of your bank account".

Melatonin's Protective Role

Melatonin, produced primarily during nighttime sleep, is both a sleep regulator and a potent anti-cancer agent. This hormone enhances immune function, inhibits tumor angiogenesis, and provides antioxidant protection against DNA damage. Sleep disruption significantly reduces melatonin production, compromising these protective effects.

Our internal biological clock regulates DNA repair, gene expression, metabolism, and hormone production. When circadian rhythms are disrupted, DNA damage can accumulate while cell growth becomes dysregulated, creating an environment conducive to cancer development.

Quality sleep strengthens your immune system. It boosts natural killer cells and other defenses that help spot and destroy early cancer cells. On the other hand, chronic sleep deprivation weakens this protection and disrupts immune balance.

Aim for 7–8 hours nightly in a cool, dark, quiet room, avoiding blue light, caffeine, alcohol, and large meals before bed. If sleep problems continue, see a healthcare provider, as untreated disorders like sleep apnea can sharply raise cancer risk. Ultimately, quality sleep works best alongside other healthy habits—not smoking, moderate drinking, healthy eating, and regular exercise—to give your body its strongest cancer defense.

Alongside healthy sleep and lifestyle habits, early cancer screening is essential. Detecting cancer early, often before symptoms appear, significantly improves treatment success and survival. Regular screening for cancers such as breast, colorectal, and lung cancer is widely recommended and can make a real difference in outcomes.

About BGI Genomics

BGI Genomics, headquartered in Shenzhen, China, is the world's leading integrated solutions provider of precision medicine. Our services cover more than 100 countries and regions, involving more than 2,300 medical institutions. In July 2017, as a subsidiary of BGI Group, BGI Genomics (300676.SZ) was officially listed on the Shenzhen Stock Exchange.