The recent melamine-contaminated Sanlu milk powder incident has received a lot of attention, with a small number of infants and children suffering from kidney stones, hydronephrosis, and even kidney failure resulting in death. However, many adult patients in our clinic asked if they also consumed milk powder and dairy products for a long time, and some milk powder was also detected to contain melamine, so they were worried whether they would also develop similar kidney stones, and whether they could continue to consume milk powder in the future. According to national statistics, so far, no adult cases of urinary stones due to consumption of melamine-containing dairy products have been clinically detected. Why is this? First, the diet of adults is completely different from that of infants and children, and dairy products are not a major food source for adults. Even if adults consume melamine-containing dairy products, their intake is extremely limited and their concentration in the body is very low, so they can be excreted through the kidneys. Moreover, the filtration function of the kidney and the peristalsis of the ureter are better in adults than in infants, so it is not easy to form stones. In addition, experts from the US FDA have evaluated the safe amount of melamine intake in humans and found that a 60 kg adult consuming no more than 2.5 kg of milk powder containing 15 mg/kg of melamine a day will not cause urinary damage, and generally speaking, an adult’s daily intake is much lower than that amount, so the possibility of urinary stones is very small. It should be clarified that many people think that melamine is a “cyanide” and is highly toxic, but this is actually a misunderstanding. There is no evidence of tumor induction in humans. Therefore, adults need to be aware of the dangers of melamine to the human body, especially to infants and children, and to stay away from “tainted milk powder”, but there is no need to panic and look at “milk” with fear. The actual fact is that milk and dairy products are an important source of nutrition.