a narrow opening produced by cleavage or separation of parts. 2. cleavage (def 1). 3. Anatomy. a natural division or groove in an organ, as in the brain. verb (used with object), fissured, fissuring. 4. to make fissures in; cleave; split.
A diet rich in potassium helps to counterbalance some of sodium's harmful effects on blood pressure. Foods that are good sources of potassium are listed in the Food Sources of Potassium table on the next page.
Potassium is a crucial nutrient, playing key roles in muscle strength, nerve function and heart health. And if you don't get enoughâ4,700 mg a dayâit could lead to a deficiency, complete with fatigue, muscle cramps, heart palpitations and dizzy spells. Yikes. You've probably heard that bananas are packed with potassium, which is true. This tasty staple is a great option for an ample dose of the nutrient, with 422 mg in each medium-sized serving according to the USDA Nutrient Database.