The main function of deep-sea fish oil is to lower cholesterol and prevent vascular diseases. EPA is called "vascular scavenger", which has the function of dredging and cleaning the heart blood vessels, thus preventing a variety of cardiovascular diseases.

DHA is an indispensable material basis for the formation, development and operation of brain cells, and can also help activate weak retinal cells, thus playing a role in nourishing and strengthening the brain, improving vision and preventing myopia.

In addition, DHA is an essential component in breast milk, which can enhance human immunity. Deep-sea fish oil is suitable for diseases such as hypertension, high cholesterol, hyperlipidemia, cerebrovascular disorder, myocardial infarction, arteriosclerosis, glaucoma and cataract.

The fantastic efficacy of publicity materials has puzzled many consumers, but the explanation of professional nutritionists is quite different from his boasting.

Bian Huawei, deputy director of the Nutrition Department of the Third Affiliated Hospital of Sun Yat-sen University, said that deep-sea fish oil is equivalent to ordinary plant edible oil, and vegetable oils such as peanut oil, sesame oil, soybean oil and millet oil all contain the so-called nutrients of deep-sea fish oil, that is, multiple fatty acids. Bian Huawei explained that the so-called EPA and DHA are actually abbreviations of two kinds of polyunsaturated fatty acids, which are abbreviated into English and look like that.

The instructions revealed the secret.

In fact, it's not that ordinary consumers can't see the secret in deep-sea fish oil. Ms. Xu, a Beijing consumer, is a "turtle". In the United States, Xu once bought two boxes of original deep-sea fish oil produced by American companies. After returning to Beijing, Xu bought another box of deep-sea fish oil of the same brand in Beijing, but accidentally found that the contents of the Chinese and English instructions were quite different. Ms. Xu said angrily that the Chinese manual is simply out of thin air and absurd.

According to Ms. Xu's comparison, the Chinese manual of this brand of deep-sea fish oil is compared with the English manual, and there is an extra paragraph: "Deep-sea fish oil has the functions of lowering cholesterol and preventing cardiovascular diseases, preventing blood coagulation and thrombosis, relieving stroke, reducing arteriosclerosis and hypertension, reducing blood viscosity, promoting blood circulation and eliminating fatigue. Taking this product for the elderly can reduce the possibility of developing Alzheimer's disease. " This statement means that deep-sea fish oil has therapeutic functions.

A person from the US Food and Drug Administration said that the deep-sea fish oil sold in the market belongs to health care products rather than medicines, so the efficacy promotion is restricted by laws and regulations. Relevant persons of the Food and Drug Administration think that the specific contents of the Chinese instructions for the above-mentioned deep-sea fish oil are exaggerated.

Another careful consumer found that in addition to efficacy publicity, there are three more words on the Chinese manual: follow the doctor's advice. He said that these three simple words are actually to mislead people into the framework of "this is a drug". In addition, the Chinese manual also "deliberately" missed a sentence: daily life.

The value is undetermined, which means "daily dose not specified".

On the bottle of a certain brand of deep-sea fish oil that a patient came to consult, Bian Huawei, a nutrition expert in the Third Hospital of Sun Yat-sen, found an English word meaning "No domestic sales". Bian Huawei revealed that this is an Australian brand of deep-sea fish oil.

He believes that the potential meaning of this sentence is that there are still many uncertain factors in the product, such as safety. "This may mean some hidden dangers, and international and domestic businesses do not rule out the possibility of hiding hidden dangers for commercial purposes." Bian Huawei said angrily.

Eating more may be harmful.

"I don't recommend people who come to consult nutrition to eat deep-sea fish oil." Bian Huawei said that it is not excluded that deep-sea fish oil has health care functions, but eating too much may also cause harm to the human body.

Bian Huawei said that deep-sea fish oil is actually a kind of fat, a simple polyunsaturated fatty acid, and each fat has so-called adverse reactions when used alone. Therefore, from the point of view of nutrition, doctors never advise people to eat only one kind of fat, but all kinds of fats.

For people who prefer unsaturated fatty acids in their diet, such as some vegetarians, nutrition believes that vitamin E or vitamin C should be taken properly to prevent side effects. Taking deep-sea fish oil as a health care product other than the normal diet will undoubtedly increase the calorie intake in people's diet, and it is also a eating habit that is not conducive to human health.

Bian Huawei said that the so-called role of deep-sea fish oil propaganda is true, such as softening blood vessels, but the medical community has not reached a quantitative index of softening. "It is very likely that the so-called role is not reflected, but the side effects such as fat accumulation and peroxidation are reflected."

Teacher Liu, a graduate student majoring in food chemistry at South China Agricultural University, believes that deep-sea fish oil, as a health care product, has not been verified by clinical trials, nor has it been proved to be safe for a long time like ordinary food. The effect and toxicity of fish oil are not credible only by merchants.

Marine experts:

"I never spend money on deep-sea fish oil"

Mr. Yang studies the environment and is the head of the Environmental Monitoring Center of Nanhai Branch of the State Oceanic Administration. He said that from the environmental point of view, the deep sea is indeed less polluted than the shallow sea, but the specific situation depends on the location. There are many credible ingredients in the promotion of deep-sea fish oil, but it seems that there is no inevitability to associate it with food. Mr. Yang said that the fish in the sea are swimming and the sea water is flowing. There is no way to say that there is less pollution in the deep sea and the quality of fish oil is good. Mr. Yang said he didn't want to comment on deep-sea fish oil, but he said he wouldn't spend money on deep-sea fish oil because it was unnecessary.

Nutrition expert: the stability of deep-sea fish oil is worth discussing

After detailed information inquiry and research, Qing Wu, an associate professor in the Department of Food Chemistry of South China Agricultural University, concluded that deep-sea fish oil does have its unique contents, namely DHA and EPA. However, it is worth discussing whether the existing health care product deep-sea fish oil can provide these nutrients for human body. Instead of spending a lot of money on fish oil, it is better to eat fish directly.

Professor Wu said that the content of polyunsaturated fatty acids in deep-sea fish is indeed higher than that in freshwater fish, and the composition of polyunsaturated fatty acids in different fish species is also different. Professor Wu introduced that the chemical structures of DHA and EPA refer to docosahexaenoic acid and eicosapentaenoic acid respectively. Freshwater fish and vegetable oil are not necessarily available, or the content is not as good as that of deep-sea fish. For example, peanut oil is mainly eicosatetraenoic acid, so although it is all unsaturated fatty acids, its composition is different.

However, Professor Wu pointed out that the chemical structures of DHA and EPA, namely eicosapentaenoic acid and docosahexaenoic acid, are very unstable and easy to be oxidized, resulting in low storage resistance of fish oil, and air, light and metal ions during processing may lead to its oxidative decomposition.

In order to know more, we specially consulted Dr. Gu, who came back from the United States as the general manager of Shanghai Zikang Baojian Co., Ltd., and she affirmed that there has been a news release in the United States, "Preventing mercury poisoning-women and children should use deep-sea fish oil with caution." In fact, in the American market, this fish oil health product, which is eagerly sought after in China, is not very popular in the United States.

Expert reminder

Since the gutter oil incident caused public anger on the Internet, the "trump card" deep-sea fish oil in consumers' hearts has also fallen into crisis.

It is reported that "deep sea fish oil" DHA contains EPA, which will lead to precocious puberty in children, and many fish oils are made from fish leftovers, and mercury residues generally exceed the standard, which is more harmful than waste oil. Wang Dahong, a senior expert in the industry and chairman of the Market Working Committee of China Health Care Association, told the reporter of Life Times: "Whenever I see someone spending hundreds of dollars to buy so-called imported high-end goods, I feel that consumers are too innocent. Most of the domestic deep-sea fish oil has problems: the quality is unqualified, the products are not standardized, and even fraud is widespread! "

Fish oil hits the "import card"

On July 10, the reporter of Life Times visited the largest wholesale market of He Shili health products, and was deeply touched by three phenomena. One is the fire of deep-sea fish oil. It ranks with lecithin and calcium as the "staple food" in the eyes of wholesalers. Many wholesalers told reporters that such products have been selling well and are the best sellers; Second, the identity is "noble". The reporter visited seven wholesale stores, six of which claimed to be imported from the United States, Germany and Australia. , but the place of origin is written in Kaifeng, Henan; Third, the price is cheap. A bottle of deep-sea fish oil labeled "Aoqikang" in the United States, the wholesale price of 100 capsules is only in 8 yuan. The wholesale price of other brands is also around ten or twenty yuan, while the retail price is horribly expensive, which is three times or even 10 times higher than the wholesale price.

The quality of these deep-sea fish oils gives Wang Dahong a headache. "If you want to know how serious its problem is, you might as well know its two major sources of raw materials first." Wang Dahong said that in foreign countries, one is extracted from deep-sea fish such as cod and salmon, and its DHA and EPA content is generally 30%, which is called natural fish oil; The other is all kinds of miscellaneous fish. The big ones are sorted out and sent to the market for sale, and the rest are sent to feed mills for processing into fish meal, and then the incidental miscellaneous oil is made into industrial fish oil. Generally speaking, natural fish oil is safe and reliable, but the price is more expensive; Industrial fish oil is relatively cheap, but pollutants such as formaldehyde and heavy metals may be introduced in the production process, so the safety is poor.

Wang Dahong told reporters that there are many problems with deep-sea fish oil in China. The most serious thing is fraud. It is obviously produced by chemicals, but it is said to be natural. It's obviously miscellaneous fish, but it's cod. Many claims on the market are raw materials of deep-sea fish oil, which may not even be fish. In China, the raw materials of fish oil are divided into three grades: food grade, feed grade and industrial grade. In order to make huge profits, some producers who have no moral bottom line use feed-grade and industrial-grade raw materials and process them into soft capsules for sale as food.

The quality of soft capsules other than fish oil particles also varies greatly. The best is extracted from cow bones and cowhide, the worst is extracted from pig skin and chicken skin, and the worst is some scraps when making leather jackets. "Like 8 yuan 100 grain of fish oil, it must be fake. The raw material is likely to be inferior salad oil with fishy smell, and the capsule is likely to be waste leather glue or recycled glue. " Wang Dahong said.

"Many products that are claimed to be imported from abroad are actually produced in China. Labeling becomes a foreign product. " On July 12, the reporter called a wholesaler of health products, who claimed that the products came from "Alaska Health Group". The other party said that the wholesale price of 100 tablets was 22 yuan, and the products were imported from the United States, with relevant national approvals. However, in the health food inquiry system of the State Administration of Pharmaceutical Products, the reporter did not find relevant information.

Alaska is hard to find "deep sea fish oil"

When it comes to deep-sea fish oil, most people in China think of Alaska. Wang Dahong said that this is actually a marketing concept played by merchants since 1998. This is because Alaska is close to the Arctic Ocean, which is relatively cold, and the deep-sea fish produced there are high in DHA and EPA. However, a survey by the reporter of Life Times found that fish oil is hard to find in Alaska, the "origin" of many fish oils.

On July 12, the reporter saw in the official website of Alaska Fisheries Development Office that the export of deep-sea fish and other seafood is its main economic force, and fish oil is only a by-product. The fish oil production in this area is less than 1% of the global total. Before 1999, the fish oil produced was mainly used for human consumption. After 2000, fish oil was more used in fishery culture-added to the feed of salmon. The reporter also contacted the Alaska Seafood Market Association, which is currently only responsible for promoting frozen Alaska salmon, cod and crabs in China, and does not involve fish oil products.

A few years ago, a reporter from Life Times went to Alaska for an interview. In a city as big as Anchorage, fish oil can't be found, and few locals have heard of deep-sea fish oil. The reporter saw in the international trade market development bureau of the government that the shelves in the hall were full of samples of various export products, many of which were fish products, smoked salmon, fish floss and caviar ... After careful reading several times, there was still no "Alaska deep-sea fish oil".

When the reporter asked about fish oil, Takaichi Tsuda, a Japanese expert in charge of the research, immediately said: "We have never verified whether the' Alaska deep-sea fish oil' on the China market is all extracted from fish caught in Alaska." According to Tsuda, most fish oil exported from Alaska is in bulk and marked as unprocessed. This fish oil can be used as feed additive or other industrial purposes, and is not the main raw material for making capsules. In the business directory of Alaska Seafood Market Association, there are nine companies that produce fish oil. But according to the reporter, most of these companies are not local companies in Alaska, some are in Seattle, and some are in California. Several export officials also speculated that some healthy fish oil on the market in China may be processed in other US states or China.

Not only is fish oil hard to find, but the concept of "deep sea fish oil" is not recognized by Americans. Fish oil is a very popular health care product in America. On the website of GNC, a national chain store, a bottle of 180 salmon fish oil costs 14 dollars, and there are often promotional activities of buy one get one free. The reporter also saw in Wal-Mart, Costco and other supermarkets in the United States that fish oil has many sub-products according to its source, such as fish oil, salmon oil and cod liver oil. , has never been collectively referred to as "deep sea fish oil". None of the major brands of fish oil such as Jian 'anxi claims to be "deep sea fish oil".

Eating fish three times a week is better than eating fish oil.

So, does fish oil have a health care function? Yang Yuexin, director of the Food Nutrition Evaluation Office of China Center for Disease Control and Prevention, and Cheng Yiyong, chairman of the China Nutrition Society, said that the DHA content of China people did not meet the intake requirements. Although the functions of fish oil in regulating blood lipid and strengthening brain have been confirmed by many studies, there is no definite conclusion that it can lower blood pressure, prevent Alzheimer's disease and reduce vision. Wang Xingguo, executive director of Dalian Nutrition Society and director of the Nutrition Department of Dalian Central Hospital, said that whether fish oil is useful depends on whether the product quality is excellent. To this end, the experts made the following suggestions:

Choose a place with high credibility. Wang Dahong suggested that it is best to go to a large reputable supermarket, shopping mall or product chain store to buy.

Don't be superstitious about importing, be sure to see the place of origin. There are only two or three kinds of imported fish oil with quality assurance. If the destination of origin is domestic enterprises, we should be more cautious. An industry expert said that he only dared to buy fish oil produced by a domestic enterprise in Shantou.

Don't buy anything below 50 yuan. Wang Dahong said that the retail price of 100 fish oil is around 50 yuan, which is more in line with the cost method. It is best to choose a big brand that not only makes best-selling nutritional supplements such as fish oil and lecithin, but also provides other health care products. From the taste point of view, good deep-sea fish oil is mainly fragrant, with a little fishy smell, and poor quality will have a more serious fishy smell.

Eat fish three times a week, so you don't have to eat fish oil. Yang Yuexin suggested that eating fish at least three times a week can basically ensure the intake of unsaturated fatty acids, and there is no need to supplement it with fish oil health products.