Ashley Graham is sharing the personal reason she decided to stop breastfeeding her twin sons when they were 5 months old.

The 35-year-old model said on "The Daily Show" Tuesday that with her first child Isaac, now 3, she thought she could "only breastfeed," but learned she had to set boundaries for her own well-being with her twin sons Malachi and Roman.

"I was like, 'I'm not doing this. This is not working here,'" she told guest host Chelsea Handler, saying breastfeeding the twins was "a lot of work."

The model said she ended up switching her twins to formula. Both sons, now 1, are currently doing just fine, she said.

"I stopped breastfeeding when they were 5 months and I gave them the best formula I could find in America," she said. "...And these little guys are so strong and so happy, so I don't think we should be telling people how they should be feeding their kids."

The U.S. Dietary Guidelines for Americans and the American Academy of Pediatrics, citing health benefits for both moms and babies, recommend infants be exclusively breastfed for the first six months, and as complementary foods are introduced, for one year or longer.

In practice though, many mothers find breastfeeding challenging, are physically not able to breastfeed or choose not to.

Many doctors suggest bottle feeding as a suitable alternative in these situations.

In the past, Graham has shared images on Instagram of herself breastfeeding her children, sharing what her life is like as a mom of three.

She told Handler she hopes to demystify the experience of motherhood.

"There's not one thing I wanted to be left in the dark, especially with how your body is changing when you're pregnant and stretch marks and saggy skin, formula, breastfeeding," she said, later adding of her experience as a mom, "This has been a journey."