Getting less than five hours of sleep each night is linked to higher levels of oxidative stress in your blood compared to getting seven or more hours. This means your body might be producing more harmful free radicals when you don't sleep enough.

If you have depression and consistently sleep less than five hours a night, your body's chemical balance shifts significantly toward oxidative stress compared to people who sleep normally. This suggests that poor sleep directly worsens this internal imbalance, even when factors like age and gender are taken into account.

People who are anxious and sleep less than five hours a night tend to have higher levels of oxidative stress in their blood compared to those who sleep normally. This suggests that not getting enough sleep might worsen the body's chemical balance, especially for those already dealing with anxiety.

This claim suggests that how much you sleep at night does not change the levels of a specific antioxidant enzyme in your blood. Whether you get less than five hours, five to seven hours, or more than seven hours of sleep, your body's natural defense against oxidative stress stays the same.

If healthy women between 30 and 55 only sleep 3 hours a night for two nights in a row, their skin shows more signs of cellular damage from stress—like rust forming on metal—because a chemical called malondialdehyde goes up.