Kidney donors generally do well over their life span. Several scientific studies have clearly shown the subjects who donate kidney have similar life expectancy as any other healthy adult. You should exercise a healthy life style which includes non-smoking, regular aerobic exercise, maintain normal body mass index (BMI), consume healthy diet which has moderate salt content, rich in fresh fruits and vegetables and regular protein content.
I must mention that higher than recommended protein intake may theoretically increase metabolic load on your remaining kidney. Thus, you should consume probably around 0.8 to 1.0 gm/kg of body weight/day of protein. Periodic physical examination by your physician is also recommended. It should not affect your LIC policy but I suggest you contact your insurance agent to confirm this issue.