In Anthony Bourdain’s 2000 book "Kitchen Confidential," he exposed the secrets of the restaurant world, and advised customers not to order fish on Mondays. At the time, fish markets were closed on Friday nights in New York City, so fish served on Monday was the same fish the restaurant had on Friday — but this may not be true today.

A decade after "Kitchen Confidential," Bourdain changed his stance on eating fish on Mondays, citing changes in the industry. The chef told Insider Tech that the fish special at the local pub still might not be the best to order on Mondays, but added that freshness standards in the larger industry had improved since he published his book.

Bourdain also said that American consumers have developed a better appreciation for what constitutes good seafood in terms of taste, appearance, and cooking methods. If you do order fish on Mondays, try to do so at a reputable restaurant by the water, meaning the fish likely traveled a lesser distance and is therefore fresher.