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On September 17th, 1998 the Ithaca Journal ran its first "Ask A Scientist!" article in which Professor Neil Ashcroft , who was then the director of CCMR, answered the question "What is Jupiter made of?" Since then, we have received over 1,000 questions from students and adults from all over the world. Select questions are answered weekly and published in the Ithaca Journal and on our web site. "Ask A Scientist!" reaches more than 21,000 Central New York residents through the Ithaca Journal and countless others around the world throught the "Ask a Scientist!" web site.

Across disciplines and across the state, from Nobel Prize winning scientist David Lee to notable science education advocate Bill Nye, researchers and scientists have been called on to respond to these questions. For more than seven years, kids - and a few adults - have been submitting their queries to find out the answer to life's everyday questions.

Previous Week's Question Published: 24 July, 2003 Next Week's Question
You may look like what you eat
Question
Will your skin change color if you eat enough of a colorful food? (For example, if you eat a lot of carrots, will your skin turn orange?)

Question
The answer to this question depends on the colorful food that you eat. The example you mention, carrots, is one of the many cases where it is true; you will turn a bit orange. Carrots are orange because they have lots of a colored biochemical (a "pigment") called, cleverly enough, carotene. Pure carotene has a deep orange color. It dissolves in oil but not in water, and it is stored in body fat. Carotene also absorbs ultraviolet (UV) light from the sun that can damage body tissues such as skin. The skin of people who intentionally consume pure carotene does change color, but just a little. They don't look like walking carrots, but rather the overall change in the color of their skin is measured by a device that measures the amount of each color of the rainbow that the skin reflects.

Many of the red, orange, and yellow pigments in colorful foods act in similar ways to carotene. Another example is the red color in ketchup, called lycopene. Some deeply green foods, like spinach and broccoli, have several colors including carotene. People who consume colorful foods, which are rich in these compounds, tend to have skin that is slightly less sensitive to the sun, though no one should stay in the sun too long just because they ate a big bag of fries with ketchup.