What is the primary effect of excess caffeine intake?

Excess caffeine intake primarily leads to insomnia due to its stimulant properties. Caffeine works by blocking adenosine, a neurotransmitter that promotes sleep, which can interfere with the sleep-wake cycle. When consumed in high amounts, caffeine can prolong wakefulness, decrease sleep duration and quality, and lead to difficulty in falling asleep. This impact on sleep can result in a cascade of effects on overall health, as adequate sleep is essential for various bodily functions.

Although nausea, bloating, and weight gain can occur with excessive caffeine consumption, they are not the primary effects. Nausea can happen, particularly in those who consume caffeine on an empty stomach or in large quantities, but it tends to be more of a secondary response rather than a direct result of caffeine’s action. Bloating may also occur but is less common and not directly linked to caffeine itself. Additionally, weight gain is generally not associated with caffeine intake; in fact, moderate caffeine consumption is often considered to have a mild appetite-suppressing effect.