Chinese students and their anxious parents go to extreme lengths to ensure teens are in tip-top shape physically and mentally to take the National College Entrance Exam this Thursday and Friday.

Students prepare for the upcoming National College Entrance Exam at class.

Here's one for the books, however, an extraordinary case that set the nation abuzz when photos went viral, showing public school students studying in a classroom - almost each with an amino acid drip. The high school in central China's Hubei Province was specially equipped with medical stands, tubes and sterile bags of solution. Drips were administered by a nurse.

Parents prevailed on school authorities to permit the drip because students were too busy studying at night and didn't have time for this extra nutrition.

Amino acids, the building blocks of protein, also promote healthy brain function, but nutritionists say drips and supplements are unnecessary if people eat a balanced diet.

The drip is just one example of how Chinese parents are trying to inject their young scholars with everything possible to promote health. There are also "lucky foods."

The exam, likened to the ancient imperial examination, is widely considered the most important test in a student's life. It's the gateway to college and a career. A high score means a good school and preferred major.

Lucky and big meals

Traditional snacks with lucky names like zhuangyuan bing (No. 1 Scholar cake), zhuangyuan zong (No. 1 Scholar Chinese Rice-pudding) and ding sheng gao (destined for success cake) are all popular. They contain nothing special but may have a reassuring, placebo effect.

Restaurants are pushing "lucky" dishes with names, such as jin bang ti ming (name published on the success list) and bu bu gao sheng (attain eminence step by step).

When 100 used to be the top score (now it's 150), parents would feed one youtiao or fried dough stick and two eggs - 100.

On the way to the exam, students may avoid taxis with license numbers containing the numeral 6, because in Shanghai dialect the word for 6, luo, means to fall or fail. Students may carry good luck charm paper blessed by a monk.

But parents know lucky-name foods or taxi license numbers won't give students an edge. Apart from relentless study, parents swear by "real strength" - serious nutrition.

High school senior Jess Lin find meals increasingly rich in nutrition and symbolism these days. Eggs of pigeon are common pre-exam sources of protein and energy.

Big-head fish (spotted silver carp) is said to improve memory because a big head suggests a big brain. In traditional Chinese medicine, animal body parts are said to correspond to human body parts, head to head, heart to heart, and so on.

Walnuts are said to benefit the brain because the nut's outside is crinkled like the surface of the brain. In fact, walnuts, which are high in an Omega-3 fatty acid, are good for the brain.

"This is a crucial time, she needs sufficient nutrition for her final battle," Lin's mother says. "She's under great pressure, which I cannot do much about. But at least I can provide her a good meal, which may help a little."

The tradition of intense nutritional reinforcement before the big exam can be traced back to 1977 when the exam was revived after the "cultural revolution" (1966-1976).

Today a hot topic online is nutrition for the entrance exam. Internet users report nutrition changes over time: the Sugar Water Age, the Malted Milk and Egg Age, the Food Protein Age and the Nutrition Supplement Age.

The Sugar Water Age was the difficult period from 1977 to 1980 when sugar (brown or white) was the only added nutrition parents could afford. Then came malted milk powder when families had more money; they could also afford eggs. Food protein such as meat, chicken and fish became available from 1985 to 1992.

Since 1995, nutrition supplements for energy and memory have become popular and affordable, and parents have seized on them. Injecting amino acid solution, as in the case of the Hubei students, is one of the latest trends.

A recent survey among third-year high school students indicates around half take supplements, especially to fight fatigue and improve memory. The survey by students at Fudan University's Medical School covered 925 students in 10 schools, all facing the exam.

More than 20 percent of respondents said they took the supplements for health, while many others said their parents insisted, or they were just following the crowd.

"Everybody is taking reinforcement; I am afraid my boy will be left behind if he doesn't," Zhao Jianguo says of his son who will sit the test. Now the youth takes Omega-3 fish oil capsules daily and an evening cup of American ginseng tea to help him study.

Fish oil, amino acids and B vitamin complex are very popular.

Popular traditional Chinese tonics include hong jing tian (rhodiola rosea or arctic root), ginseng, and even expensive dong chong xia cao (cordyceps or caterpillar fungus).

No medical proof

Though many supplements are said to improve memory, there is no medical proof that any product is very effective, according to independent nutritionist Zeng Kaihong. Most fatigue-fighting products work for physical, not mental fatigue, she says.

Diet reinforcement is considered a safer way to ensure students are healthy but nutritionists warn against overdoing it.

Yang ("hot" energy) predominates in most teen constitutions, says Professor Sun Xiaosheng of Guangzhou University of TCM. Lots of late study and stress often cause excessive yang. Thus, "hot" foods, such as ginseng, may aggravate the problem, causing insomnia, restlessness and an over-active brain.

"A balanced diet with all the basic nutrition is enough for normal brain function," Professor Sun says. He warns against a sudden change in diet before the exam, lest unfamiliar foods cause allergy or digestive discomfort.