Oranges, lemons, and grapefruits are highly acidic, which can irritate an empty stomach and trigger acid reflux or stomach upset.

Rich in magnesium and potassium, bananas may increase blood levels of these minerals too quickly, potentially causing an imbalance or digestive issues.

Pears contain raw fiber that can damage the delicate lining of an empty stomach, leading to bloating or indigestion.

The high levels of tannic acid in tomatoes may irritate your stomach lining, causing acidity and discomfort when eaten without food.

Pineapple's strong enzymes, especially bromelain, can lead to heartburn or stomach upset when consumed on an empty stomach.

This fruit contains tannins and pectin, which can interact with stomach acids, forming clumps that may lead to indigestion or even gastric issues.

Although hydrating, watermelon is high in fructose and can overload your system, leading to bloating or upset stomach when eaten alone.

Mangoes are rich in natural sugars, which can spike blood sugar levels rapidly, causing an energy crash later on.

Lychees can disturb your insulin levels, potentially causing low blood sugar or discomfort if eaten in the morning on an empty stomach.