Getting Too Much Bright Light at Night May Increase Your Cancer Risks. Here's Why

Research has found that exposure to artificial light at night is linked to an increased risk of breast cancer

April 18, 2025 · 1 min · 71 words · Matthew Trujillo

Table of Contents

Why Might Bright Light Exposure Increase Cancer Risk?

These increase the risk of breast cancer and accelerate tumor growth.

The problem is not bright light per se.

An illustration of a person on their phone, early in the morning.

Illustration by Mira Norian for Verywell Health

Blue light at night can suppress melatonin secretion and shift circadian rhythms much more so than white light.

2018;33(4):369-379. doi:10.1007/s10654-018-0368-x

Harvard Health Publishing.Blue light has a dark side.