Ron Klain loves Tab so much that his wife bought him a year's supply of the discontinued soda. But it's already gone.

• Ron Klain really loves Tab.
• Klain's wife bought him a year's supply of the discontinued diet soda. But it's already gone.

Being the White House chief of staff isn't easy. A definitive book on the gig found that past chiefs of staff blamed the job for a heart attack and shingles. One of President Donald Trump's chiefs told author Chris Whipple that things were 50 times crazier than what was publicly known.

The Washington Post reported on Tuesday that Ron Klain, Biden's White House chief of staff, is up at all hours. And he relies on a niche source for his caffeine fix to fuel his work: Tab, Coca-Cola's first diet soda that was a cultural staple in the 1970s and 80s.

The Post reports that Klain loves Tab so much that his wife, Monica Medina, a high-ranking State Department official, gifted him a year-long supply when news broke last fall that Tab would be phased out. But Klain told the paper he quickly guzzled through his stash.

"Tab is gone — it's a problem I've been unable to fix in my first year as chief of staff," Klain told The Post.

Politico's West Wing Playbook previously detailed Klain's decades-long love affair with the soft drink "for beautiful people."

"You quickly learn that TAB brought him a special joy," Moe Vela, who worked with Klain in the Clinton and Obama White Houses, told Politico.

Despite all the Tabaholics, demand for Diet Coke easily surpassed that for Tab in recent years, The New York Times reported. As for Diet Coke fans, former President Donald Trump reportedly loved it so much that he had a button on the Resolute Desk that could quickly summon one to the Oval Office.

"I have gotten more sympathy emails and texts about this story than the many times that Trump or Pence have attacked me. And honestly, this is definitely a harder blow," Klain wrote on Twitter in October when Coca-Cola announced it would discontinue Tab.