Just two weeks ago, he visited an orphanage as part of his work as the North Korea program director for the relief organization Mercy Corps.
He said the last protein children had eaten was in January -- eggs.
"That tells us not only are they not getting a balanced diet but in terms of the rations, they're getting only about 60% of what a child needs," he said.
Austin describes widespread severe malnourishment and "an entire generation" that is "stunted physically, developmentally because of chronic malnutrition."
According to Austin, in seven visits since 2007, he has been to dozens of orphanages and hospitals and more than 19 private homes.
He says he is troubled that the United States plans to call off a massive shipment of food aid as a result of the anticipated rocket launch by North Korea between now and Monday.
Pyongyang insists that the rocket is necessary to put a weather satellite in orbit, but Washington and Seoul consider it a ballistic missile test in disguise. Such launches by North Korea breach U.N. Security Council resolutions.
Under a recent food deal with the United States, North Korea agreed to refrain from long range missile launches and nuclear tests. In exchange, the United States would provide what Austin described as a year's worth of corn-soy porridge mixed with vegetable oil for children younger than 10 and pregnant women.
The food "wouldn't taste delicious but it saves lives," Austin said, noting that it would have helped 2.4 million people.
At the White House, President Barack Obama's aides suggest their hands are tied after Pyongyang announced the launch just weeks after the food deal was agreed.
The North Koreans' "blatant disregard for their commitments makes it impossible for the United States to provide the nutritional assistance that it had hoped to provide for the North Korean people," said Jay Carney, the White House press secretary.
Some observers have doubts about the White House's approach.
"I have real questions about whether we should have linked humanitarian food assistance to the nuclear missile program in the first place," said Mike Green, who was senior director for Asian affairs at the National Security Council during the Bush administration. "It is not the fault of the average North Korean who needs the food, who is at starvation level, that the regime is developing nuclear missiles."
He said the threatened missile launch was a "provocation that should have been predictable."
But Green acknowledged that if the North Koreans flaunt the deal, sending the food "would be a political liability for the administration at home, and it would look weak internationally."
Austin of Mercy Corps was careful not to criticize the Obama administration. But he did say the administration had previously made it clear it would send food to North Korea if there was a verified need for that aid.
"We know there is a need and we know we can met the need. As a humanitarian organization we are saying there is an opportunity to do that," Austin said. "I don't want to assign blame. But I'm saying there is an opportunity to engage positively and constructively with a group of people the White House describes as innocent and starving, and we can do that."
