Professor Wu Yangfeng reported that between 1985 and 2000, the rate of overweight and obese children increased 28-fold.
His comments were published in a special Chinese edition of the British Medical Journal.
Research shows that now a fifth of the world's overweight and obese people are from China, and that number is rising fast.
Professor Wu Yangfeng told BBC that this was a serious health problem, asking Chinese authorities to act now to prevent it from worsening.
The cause seems to come from increased economic development in China. There are the changes in diet and a decreased amount of exercise.
Other Chinese health problems addressed in the British Medical Journal involves the impact of passive smoking on Chinese women, the long-term impact of the one child policy and the SARS crisis.
