Possible Clues:

• A sign of growing older: forgotten times and pressure to study
• Page studied on historical period showing development of corporation
• Cover for a fortysomething?
• Girth problem quietly studied after centuries in the past
• Historic period -- BC, apparently -- gets more weight
• Waistline concern
• Weight gain, of a sort
• Typical weight gain between 500 and 1000 years ago, before the present era