Duggar, who has 19 children, told the Christian Broadcasting Network that the warnings are a "lie".
"The idea of overpopulation is not accurate," she said.
"Because really, the entire population of the world, if they were stood shoulder to shoulder, could fit in the city limits of Jacksonville. So if you realise that aspect of it, you realise that we're nowhere near being overpopulated."
Duggar said that her family acts responsibly by buying used goods and shopping in thrift stores, adding that she is teaching her children to be "helpers and servers, givers instead of takers".
She explained that she is shocked when people say there are too many children in the world, adding: "I agree with Mother Teresa when she says, 'To say there are too many children is like saying there are too many flowers'. That's the truth of it.
"Our world needs more joy and more purpose and just the next generation to be encouraged by those that are going to make a difference for good in our world. That's our prayer for our children - they're going to be the ones making a difference."
Duggar suggested that other countries have asked for help persuading their people to have more children, adding: "I think we are so deceived when we believe [that the world is overpopulated].
"That's not true, it's a lie. And so I think the goal needs to be we need to focus on loving people and trying to reach out and make a difference for good in our world."
Duggar suffered a miscarriage late last year and recently described the news as "devastating".
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