"When I sent an email to my friends from here, I think I scared them when I told them how deep those needles go," said Walt, who has shed 48 kilogrammes off his original 179 kilogrammes.

But the rest of the weight-loss treatment is similar to the West -- exercise twice a day and good nutrition, albeit Chinese-style with rice, fried vegetables, tofu, meat and soup the staples of their diet.

As they sat down for lunch in the basic canteen they eat in every day along with other Chinese people trying to lose weight, the three looked at each other and laughed when asked about the local food.

"Don't get me wrong, the food here is good. But it's just not having certain things for a certain period of time -- it wears on you," said Alonzo.

"You're thinking about all the steaks you want to have."

The three have featured prominently in local media, prompting a Chinese woman to ask to meet Walt when she saw his photo in the newspaper and subsequently proposing to him -- an offer he refused.

"I didn't come here to find a Chinese wife," he said. "I don't need a wife."

Later, as the three walked out of a bus and onto the streets during their break, locals openly stared at them as they strolled by -- a situation the three said was even more pronounced when they first arrived and were bigger.

Taxi drivers were reluctant to stop for them due to their size, they said, which meant they were at the mercy of the hospital's transport if they wanted to get around.

"For us (Chinese people), it's very hard to see such obese people," explained Su Zhixin, their doctor.

"Alonzo is the heaviest person to have come here since our hospital was set up in 1998."

Sighing, Alonzo said it had been difficult to cope with the attention when he first got to Tianjin.

"It was unbearable, I just wanted to not go out at all. But then the weight started coming off, and I thought -- I am who I am," he said.

Walt claimed that he missed driving his car more than food in the United States, but for Alonzo, it was his children and fiancee that he pined after.