(CNN) -- In January, Carol Highsmith, 68, began a journey of threes. She had three milestones of 50 that she planned to reach by following three simple rules:
At 175 pounds, the 5-foot-1 Highsmith was at her heaviest weight. She vowed to lose 50 pounds so she could fit into a 50-year-old dress from high school. Determined to stun all her old classmates, Highsmith saw her invitation to Minnehaha Academy's 50th reunion as the catalyst to spark a lifestyle change.