Blood pressure can't change from one meal to the next. When weight is lost, many people lose a small amount of blood pressure. This is because when people lose weight, blood flow to muscles decreases. As a result, heart muscles pump less blood to the arms and legs, and fewer salt and sugar are pumped into the blood. Losing weight can help your blood pressure if it gradually reduces, stays less high for more than a month and does not cause bleeding (edema).