Science Buddies: "Ask an Expert"

Why do we only get sugar rushes from refined sugar instead of fruit sugar? Grade 3s want to know. Thanks! How long have you worked as an expert?

Hi! Refined sugar (think candy and cakes) has no fiber to slow down its absorption, so it’s digested rapidly and enters the blood stream very quickly, causing a (blood) sugar rush/high. This sugar high, in turn, causes the body to release a surge of insulin, which quickly removes the sugar from the blood to the tissues. This is what is often known as a sugar crash or “low,” and is the body’s way of signaling that it needs a quick pick-up and the quickest pick-me-up is more sugar! This launches a vicious cycle of highs and lows that lead to a deep craving for more sugar.

At the same time, sugary foods don’t provide the body any of the nutrients it needs to feel good and to sustain energy.

Importantly, natural sugar provides a longer source of energy without crashes. Natural sugar comes packaged in fruit—and fruit is a good source of fiber, which slows down the digestion of glucose so you don’t get the energy high/insulin spike followed by a sugar crash like you do when you eat refined sugar. Fruit also contains water, which helps to prevent dehydration and the tired, drained feeling that comes with it that mimic blood-sugar dips.
(From American Council on Exercise)
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