A 100-year-old influencer shared the secrets to her long life, such as a dark sense of humor and travel

• 100-year-old Mildred Kirschenbaum has 100,000 followers on Instagram.
• She advises younger people on how to lead as long a life as possible.

Neither Mildred Kirschenbaum nor her travel agent could understand why she kept appearing as an "accompanied minor" when they tried to book a flight.

It took a while, but they finally caught on. The airline's computer system couldn't register her birth year as 1923. Instead, it thought she was born in 2023.

Kirschenbaum, who turns 101 in August, told Business Insider that the unusual situation was somewhat typical of life as a centenarian.

"It was the kind of thing that might drive people crazy," she said. "But I always see the funny side."

She said it was "all about attitude" — a mantra she shares as one of the oldest influencers on Instagram, with 100,000 followers.

Now, the grandmother of nine has published a book, "," outlining her life lessons. Here are three highlights.

Don't stay angry

Kirschenbaum described her late husband, Gerald, as "her best friend," despite them arguing "every day of the week."

But, she said, they drew a line under the acrimony in time for bed.

"We'd fight about something, and the next question might be, 'Do you want salad with your meal later?'" she added. "The door was closed on the argument."

The New York native said your marriage could be in trouble if you stewed on negative thoughts. "If you're angry the first night, you could be thinking of divorce by the second night."

She also said it was important "not to go your grave with regrets." She told BI she'd been a "tough mother" to her daughter, Gayle, and had recently asked for "forgiveness."

"She accepted," Kirschenbaum said.

Develop a sense of humor

The centenarian said she had a dark — and often self-deprecating — sense of humor that has smoothed her path through life.

She said she called Gayle, who lives in Manhattan, "about 10 times a day" from her home in Florida.

"I told her, 'When I die, bury me with my phone so you can call me.'" she said.

One of her followers recently asked how she stayed fit at 100. "I exercise my mouth," she responded.

Meanwhile, strangers laugh when she makes a toast at a bar — she enjoys "Meatball Night," especially when there's a "Happy Hour" — and says, "Here's to those who wish me well, and those who don't can go to hell."

Travel the world — even if you have to wear an adult diaper

Kirshenbaum, a former secretary and model who once ran a travel agency, has visited dozens of countries worldwide.

She recently went to India — for the second time. "I flew up to the Himalayas," she said. She went to the UK in 2023 and cruised to Mexico earlier this year.

"Most people my age are afraid of traveling," she said. But, to her, it's "no big deal."

"They'll say things like, 'I won't be able to lift my suitcase or get around the airport,'" Kirshenbaum said. But, she said, strangers are "happy to help."

"I've lost some strength in my hands," she said. "If I have trouble opening a bag of pretzels or other snacks on the plane, I just ask the person next to me to open it for me."

The 100-year-old said that if you have a "leaky bladder" because of your age, invest in adult diapers before you leave. "Wear Depends," she said. "Don't let it stop you from going out and doing things."

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