Watermelon’s high potassium level is a plus for people who do not get enough of the nutrient, but too much potassium is not good for the body. In rare cases, consuming too much potassium can lead to a health condition called hyperkalemia, which can have pretty serious side effects, according to Medline Plus. This is known to happen in individuals whose kidneys have trouble filtering out excess potassium, either because of an illness or as the result of some medications. People who suffer from hyperkalemia can experience nausea, chest pains, difficulty breathing, and heart palpitations, so individuals with high potassium levels will definitely want to limit their watermelon intake.
Additionally, lycopene is also healthy in moderate doses, but can cause issues in high amounts. Eating more than 30 mg of lycopene has been shown to cause gastrointestinal distress, gas, bloating, and indigestion, per Live Science. Additionally, watermelon is high in fructose, which may also lead to stomach issues in high does, per Eat This Not That. For most people, it would take quite a bit of watermelon to reach this point, but those with sensitive stomachs may want to be extra mindful of the amount of watermelon they consume.
For most people, watermelon is a healthy choice that provides many important vitamins and minerals. It can be a nutritious and tasty snack, but, like most foods, moderation is the key to ensuring you get the most benefits out of the satisfying fruit.