Wu Xiangping, academician of the Chinese Academy of Sciences, unveils the top 10 science myths at the ceremony.

2018’s top 10 science myths in China were unveiled on Wednesday at a ceremony held by People’s Daily. All these myths have been debunked by doctors, professors, and scientists during the last year.

Myth 1: Human bodies are either acidic or alkaline

People adopting this view believe that most human diseases are caused by "acid constitution." This conclusion was propagated by certain health product vendors, quickly becoming "medical common-sense." Even the rumor that parents with higher alkaline levels are more likely to give birth to a son became common knowledge.

The truth is that acids and bases are well balanced in the human body in a complicated mechanism. It is impossible to change a person's body makeup by merely eating designated foods. In other words, abnormal blood pH is the result of disease, not a reason for it.

Myth 2: Foot pastes expel endotoxins from the human body

People holding this view believe that foot pastes effectively dispel body toxins and humidity. These pastes become black after being used on human feet, the color indicating the efficiency of the treatment. The pastes are said to be effective in removing skin stains, and may even relieve constipation and other diseases.

The truth is that by just adding a drop of water to the paste, it will start to darken.

Myth 3: Coffee causes cancer

An article said that acrylamide, a carcinogen found in coffee, could cause cancer.

The truth is that a small amount of acrylamide is released when food is heated at a high temperature. However, in China, more than half of acrylamide comes from stir-fried dishes rather than coffee. Additionally, a report by the IARC (International Agency for Research on Cancer) in 2016 said that there was not enough evidence to prove that drinking coffee could increase the risk of cancer.

Myth 4: Keeping onions in the room could prevent flu

The story goes that many years ago, a doctor visited a number of farmers during a particularly harsh flu outbreak. Every family seemed to be suffering from the bout of influenza, apart from one. The only difference between the healthy family and their less-healthy counterparts was that the former kept an unpeeled onion in every room. They explained that onions could absorb germs, and therefore the household managed to avoid the flu completely.

The truth is that onions do contain organic sulfides, which can, to some extent, inhibit bacteria. However, as influenza is a viral infection, onions would be pretty useless in this scenario.

Myth 5: Shopping receipts cause cancer

Apparently, cups and shopping receipts contain too much bisphenol A, a cancer-causing chemical. People are suggested not to hold receipts in their hands for a long time and wash their hands after coming in to contact with one, especially if their hands are wet or greasy.

The truth is that there are only 0.0139 grams of bisphenol A in a gram of receipt paper, and the amount absorbed by people who hold onto them is even smaller. For example, the daily bisphenol A intake of a cashier who works 10 hours a day is 42 times lower than the safety cut off.

Myth 6: Nicotinamide mononucleotide (NMN) could increase life expectancy to 150 years old

An article circulated online said that an affordable pill could increase life expectancy to 150. The article also attached a screenshot of the original English media report to make the claims more believable.

The effect of the pill has been widely exaggerated. Two scientists did indeed experiment on two mice in 2017, respectively aged six months and 22 months old. Results showed that NMN could admittedly slow down the process of aging and keep people energetic. However, the sample size of this experiment was too small, and human trials were never carried out.

Myth 7: Too much rice could cause diabetes

Research indicated that Chinese and Japanese people typically eat more than three servings of rice each day. The study suggests that those who eat more rice are 55 percent more likely to get diabetes, while Americans who consume one or two servings of rice per week only incur a 12 percent risk increase.

There are multiple reasons a person may get diabetes. People in northern China eat much less rice than those in the south, but diabetes morbidity in northern China is much higher.

Myth 8: Milk causes cancer

A rumor has circulated online that milk contains chemicals, makes humans mature faster, decreases brain power, stimulates cancer growth and shortens life.

Surveys on the relation between milk and cancer have proven that a cup of milk per day won’t increase the risk of cancer.

Myth 9: Table salt is not edible

In an online article, a professor related the rise of transaminase, total bilirubin, and creatinine in his blood to potassium ferrocyanide, an anti-caking agent found in table salt. He then concluded that salt in China contains this ingredient, which is poisonous and inedible.

Potassium ferrocyanide is, in fact, a legal food additive. To activate the chemical, it needs to be cooked at around 400 degrees Celcius, at which point your dinner would have already burnt to a crisp.

Additionally, potassium ferrocyanide won’t hurt an adult's health unless their daily intake surpasses 1.5 milligrams, which means consuming 150 grams of salt, while the recommended daily intake is no more than 20 grams. Therefore, regular consumption of salt should not cause any health issues.

Myth 10: Roasted garlic causes cancer

When roasted, garlic undergoes a chemical reaction in which it releases acrylic amide, which is said to cause cancer. However, the truth is that the amount of this chemical produced during the cooking process is too small to cause any risk.