麻豆影院

CU-麻豆影院 researchers show the profound effects of nighttime caffeine

Caffeine can offer more than a pick-me-up: It can keep you up and throw you off, warping time and biological rhythms throughout the body.

New research by CU-麻豆影院 scientists and colleagues shows for the first time that consuming caffeine in the evening delays the human body鈥檚 circadian clock, a natural system that influences the timing of various biological processes, including when we eat, sleep and wake.

Ingesting the equivalent of a double espresso within three hours of bedtime could delay the timing of the body clock by 40 minutes, according to the researchers.

They also showed how caffeine affects 鈥渃ellular timekeeping,鈥� namely by blocking the work of a chemical involved in sleep and energy use.

鈥淲e know we have clocks throughout our body besides our brain,鈥� says Kenneth Wright, the CU professor of integrative physiology who co-led the study. 鈥淎nd so, if caffeine is affecting the clocks in our liver and our muscles, it may be affecting how those particular tissues or organs are functioning.鈥�

Published in Science Translational Medicine in September, the study could lead to treatments for certain types of sleep disorders and help long-distance travelers mitigate jet lag, says Wright, who directs CU-麻豆影院鈥檚 Sleep and Chronobiology Laboratory.

In a 49-day experiment, the scientists tested five human subjects under low light and a placebo pill; low light and the equivalent of 200 milligrams of caffeine; bright light and a placebo; and bright light with caffeine.

Low light and caffeine 鈥� an after-dinner coffee drinker鈥檚 likely conditions 鈥� led to a 40-minute delay in the circadian clock. Bright light alone and with caffeine led to delays of about 85 and 105 minutes.

Wright co-led the study with John O鈥橬eill from the Medical Research Council鈥檚 Laboratory of Molecular Biology in Cambridge, England.

Read more about

Photography 漏 iStock/malerapaso