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Morning sun is best for weight loss

Photo of a cloud illuminated by sunlight.
Photo of a cloud illuminated by sunlight.
Ibrahim Iujaz from Republic Of Maldives This file is licensed under the Creative Commons Attribution 2.0 Generic license by its author.

People that have a moderate exposure to natural light in the morning have a better chance of losing weight and maintaining weight loss according to new research conducted by Kathryn Reid, research associate professor of neurology at Northwestern University Feinberg School of Medicine and Dr. Phyllis C. Zee, the Benjamin and Virginia T. Boshes Professor of Neurology and director of the Northwestern Medicine Sleep and Circadian Rhythms Research Program at Northwestern University Feinberg School of Medicine, that was published in the April 2, 2014, edition of the journal Public Library of Science.

The effect of exposure to natural light was found to be independent of age, sex, time of year, sleep timing, physical activity level, or caloric intake. Light accounted for 20 percent of body mass index measured in trial participants.

The researchers found that exposure to natural outdoor light for 20 to 30 minutes a day at a minimum of 500 lux produced the optimum effect on BMI. The indoor lighting that most people are exposed to during work or at home can only produce 200 to 300 lux and this level of light is not sufficient to promote weight management. Lux is a measure of luminous flux per unit area and is equal to the amount of light produced by a candle.

The researcher’s previous work has demonstrated that light and the circadian rhythm have a regulatory role in hunger and metabolism.