In hospitalized adults with moderate to severe depression, daily exposure to bright light for 30 minutes over two weeks is associated with a measurable decrease in fasting blood glucose levels compared to exposure to dim light.

Pro

Against

Evidence from Studies

Supporting (1)

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The effect of bright light therapy on glycemic control and cortisol rhythmicity in depression: a randomized controlled trial.

Randomized Controlled Trial

Human

2026

Contradicting (0)

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No contradicting evidence found

Gold Standard Evidence Needed

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Source Study

The effect of bright light therapy on glycemic control and cortisol rhythmicity in depression: a randomized controlled trial.

Score: 67

DOI: 10.3389/fpsyt.2026.1743465

Similar Assertions

For hospitalized adults with depression, exposure to bright light each day lowers the daily fluctuation in cortisol levels by about 1.27 ng/mL compared to exposure to dim light.

80%

For hospitalized adults with depression, exposure to bright light each day lowers the average level of cortisol in the body over a 24-hour period by about 1.37 ng/mL compared to dim light, suggesting a more regular daily rhythm of this hormone.

77%

In hospitalized adults with depression undergoing bright light therapy, decreases in blood sugar levels are linked to decreases in the average level of cortisol over a 24-hour period, suggesting that the body’s daily hormone rhythm and glucose control may be biologically connected.

74%