The evolutionary reason for sugar consumption by humans is thought to be the result of survival techniques by prehistoric humans who discovered that sweetness was often indicative of safe food that provided energy, while a bitter taste more often denoted toxicity. Although living conditions and the availability of safe food has drastically changed, many scientists believe that human physiology has remained the same in terms of taste. Humans might be drawn to sugar because in prehistoric times, a sweet taste generally meant that an item contained a higher percentage of fat, which would provide energy reserves for times when food wasn’t as available. The evolutionary preference for high-fat, sugary foods is thought to contribute to the increased prevalence of obesity in modern times.
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