Among people who as young adults neither drink alcohol immoderately nor smoke, those who never marry live as long as those who marry.

• 在不吸烟喝酒的年轻人里，不结婚的和结婚的活得一样长。这正好说明是因为不吸烟不喝酒而活得长的，而不是因为结婚活得长，支持结论。