Final answer:
The most important teaching plan topic for the nurse to prepare for a post-menopausal woman with a BMI of 19 would be osteoporosis prevention through adequate nutrition and weight-bearing exercise.
Step-by-step explanation:
The most important teaching plan topic for the nurse to prepare for this high-risk patient, a post-menopausal woman with a BMI of 19, would be Osteoporosis prevention. Osteoporosis is more common in women, especially post-menopausal women, due to the reduction in estrogen production, which promotes bone health. Prevention should start with a childhood diet that includes adequate intake of calcium and vitamin D, as well as weight-bearing exercise. Promoting proper nutrition and exercise early in life can help maximize bone mass and reduce the risk of osteoporosis.