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.
1 Sodium: Needed for normal cell function throughout the body. 2  Most diets contain too much sodium which is associated with high blood pressure. 3  Vitamin A: Keeps eyes and skin healthy and helps protect against infections. 4  Vitamin C: Helps heal cuts and wounds and keeps teeth and gums healthy.