New Book Explores Best Times For Almost Everything

Published October 14, 2009 at 4:11 PM EDT

Journalist Mark Di Vincenzo has written a book full of answers to questions that begin "When is the best time to...?"

The carefully annotated Buy Ketchup in May and Fly at Noon addresses activities from when to buy a house to when to defrost your freezer.

So, when should you defrost that freezer? "When the ice buildup reaches one-quarter-inch deep," Di Vincenzo tells NPR's Robert Siegel. "You waste energy if you do it more or less often than that."

The title of the book begs answers, too, such as: Why is May the best time to buy ketchup?

Di Vincenzo says May is the beginning of picnic season, and you can find ketchup, mustard and relish on sale. Stores want to get customers in the door so they'll buy other items.

And why fly at noon? "Airport rush hour mimics highway rush hour — fewer people, shorter lines, less stress and aggravation," he says.

The book also delves into when students learn best — depending on whether they're exercising long-term or short-term memories.

For long-term, the best time is from 8 p.m. to midnight. The nervous system is "particularly aroused" at 8 p.m. and long-term memory improves over that time, Di Vincenzo says. For short-term memories, it's the morning.

The most surprising thing he learned in the course of researching the book, Di Vincenzo says, is that the best time to put ice on a burn is "never."

"[When] I grew up, if you had a burn on your arm or on your skin, you would just put ice on it right away," he says. "It turns out that it does more harm than good; it slows the healing process and can even cause frostbite."

And he's following his own advice: "I can tell you I stocked up — got a year's worth of ketchup in May."

But Di Vincenzo says he can't take credit for coming up with the idea for his book.

"My wife is one of those people who comes up with 10 great ideas a day," he says. "Unfortunately, I don't listen to all of them, but I listened when she said, 'Hey, you should write a book about the time to do things or buy things or go places.' "