Recent disputes about the quality standards of domestic(domestic political activities, events, and situations happen or exist within one particular country) milk(奶nǎi) have made many people think twice when drinking milk. Yet milk remains the best source of calcium, according to nutrition experts. Yogurt(酸奶suānnǎi) and cheese are good substitutes for those who can't drink milk.

Calcium is one of the major inorganic elements in the body. A lack of calcium has been linked to problems such as achy joints and bones, fatigue, poor appetite, sleeplessness and anxiousness. Osteoporosis and rickets have also been linked to a lack of calcium.

The average adult needs about 800mg of calcium a day, according to Yang Kefeng, a nutritionist from Shanghai Jiao Tong University's Nutrition Department with the School of Medicine. Pregnant women need about 1,000mg per day. Toddlers 1 to 3 years old need 500mg, children 4 to 8 years need 800mg and those from 9 to 18 years require 1,300mg daily.

Generally, the average adult is advised to drink about 250ml of milk every day. Ordinary milk is the best choice for most healthy people, while people with problems like high blood pressure, high blood fat, diabetes or metabolism problems are suggested to drink evaporated milk.

"High-calcium milk in the market is usually made by adding more calcium carbonate. Though it helps increase the calcium content in milk, it does not necessarily increase the quantity of calcium that you can absorb," Yang says.

As for the recent heated debate on pasturized milk and ultra-high-temperature processed milk, Yang suggests that both processing methods retain both the protein and calcium, while some vitamins are lost in the ultra-high-temperature processing.