Most nutrition that the human needs can be obtained from our daily diets. In order to ensure the normal functioning of our bodies,we should eat only healthy food and ensure the reasonable menu which have the suitable quantity and total kcal of food.Some food seems to be healthy, such as leftovers, leafy green vegetables, shrimps and crabs. In fact, they may harm our bodies so that we have to take more care of our daily diet. 1. LeftoversLeftovers can be easily polluted by microbial so that it must be kept in the fridge under low temperature, and being heated before having it.2. Leafy green vegetablesWhen farmers are using fertilizer, leafy green vegetables may be polluted by Norwalk virus. It’s easy for us to be infected when eating this kind of raw vegetables which haven’t been cooked.We must wash them before eating, it is better to wash it buy boiling water for a while.3.Shrimps and crabsShrimps and crabs are the major allergens to Chinese. The kind of protein that it contains may cause itchy skin, or serious asthma to our bodies.So that it is not suitable for those kind of people to have shrimps and crabs.4.cantaloupeDangerous factors: there are many cracks on the skin, which is easy infected by bacterial.There are bacteria in the skin. So if you cut the cantaloupe, the internal part will also be infected.Solution: Clean it before eat it. But it is not the best way to solve the problem .You should carefully store the half cantaloupe.It is because it is east to breed large numbers of bacteria under standard temperature so we must store it in the fridge.5.sushiDangerous factors: the serious problem of eating sushi is the infection caused by the parasite, flatworms and roundworms inside. One example is the parasite of Striped Snakehead.Although safety of eating raw fishes cannot be guaranteed, dipping sauces or Wasabi can slightly kill the bacteria.Solution: Fishes should be cooked under 145 degrees Celsius for at least 1 minute and it can kill all parasites.But that isn’t sushi at all. The only way eat raw fishes safely is to eat the product made by frozen fishes.The U.S. food and Drug Administration recommended us to freeze the fishes under 31 degrees below zero for 15 hours so as to kill all parasites.6. Packed green vegetablesDangerous factors: The leafy green vegetables including lettuce and spinach are the cause of several diseases in recent years.The most serious one is the spread of Escherichia coli in 2006,involves packed spinach,lead 199 people suffering from it,3 people dead.The are many ways for the Escherichia coli and Salmonella to infect the agricultural products such as by the discharge of animal’s feces in water or soil or by the picking and packing processes.Generally, washing them cannot solve these problems.