TOKYO (Reuters) - Teenage Japanese table tennis player Koki Niwa has been ordered to see a dietician and consume more vegetables in the run up to this year's London Olympics to fix his sloppy eating habits.

Japan's coaches have lost patience with the pint-sized Niwa over his aversion to healthy food, local media reported on Friday.

"Looking after my diet is not something I'm all that interested in," the 17-year-old, who particularly dislikes tomatoes and carrots, told the Nikkan Sports newspaper.

"But I will do what I can to try to increase the amount of vegetables I eat," added Niwa, who shocked China's world number one Ma Long at last month's Asian Olympic qualifiers.

Japan coach Yoshito Miyazaki has booked Niwa for sessions with a dietician in a bid to get the 160-centimetre, 52-kilogram player in good shape for London.

The left-hander won the gold medal at the 2010 Youth Olympic Games and won junior world titles in doubles the same year and in singles in 2011.

Niwa, who will contest the team event with Jun Mizutani and Seiya Kishikawa, has given early indications that he is listening to the eating advice.

"My favorite food is noodles and meat," said Niwa. "But I'm going to try eating green peppers."

(Reporting by Alastair Himmer; Editing by John O'Brien)