The main chemical component in monosodium glutamate is sodium glutamate. Glutamate is an amino acid and sodium is an electrolyte, both of which are inherent components of human body. All kinds of protein generally contain glutamic acid, which will be hydrolyzed and released to form sodium glutamate, and it is also contained in soy sauce.
Rumor: MSG heating can cause cancer?
The results showed that 0.2% monosodium glutamate and 2% salt solution were heated at 1 15℃ for 3 hours, and the odorless sodium pyroglutamate was only 0.0 14%. Sodium glutamate is pyrolyzed above 200℃ to produce sodium pyroglutamate, which is harmless to human body and tasteless, and may be beneficial to brain memory and cognition.
Can monosodium glutamate lead to depression and hair loss?
Studies have shown that extremely high doses of monosodium glutamate are harmful to the nervous system and endocrine system of human body. For example, a study published in the Journal of Life Sciences showed that subcutaneous injection of high-dose monosodium glutamate (4g/kg bw) can cause depression and anxiety-like behavior in neonatal rats, but this dose is equivalent to 240g monosodium glutamate (60kg) in human body. Dietary intake of monosodium glutamate (including free and bound glutamate) has little effect on plasma level. For example, the intake of sodium glutamate is 150mg/kg bw, and adults can only detect a slight increase in plasma glutamate level; Dietary intake of monosodium glutamate will not damage various organs of the human body.
Pay attention to eating monosodium glutamate
In fact, as long as you eat monosodium glutamate reasonably, it is harmless to your health. Even the European Union, which is very conservative about food safety, lists monosodium glutamate as the safest category. But when eating monosodium glutamate, we should also pay attention to the following points:
1
Patients with hypertension should not eat more monosodium glutamate.
The higher the blood pressure, the less sensitive the taste, and the stronger the taste, which is easy to form a vicious circle. Therefore, it is suggested that patients with hypertension should not eat more monosodium glutamate.
2
Intake of no more than 7.5 grams is harmless to the body.
Do not add excessive monosodium glutamate to the dishes eaten by mothers and babies within 3 months after delivery. Because sodium glutamate in monosodium glutamate enters the baby's body through milk or food, it will specifically combine with zinc in the baby's blood to generate glutamic acid that is not absorbed and utilized by the body and excreted with urine.
How should I choose the salt that suits me?
There are more and more kinds of salt in the market, including iodized salt, low iodized salt, non-iodized salt, zinc salt, low sodium salt, seaweed salt and bamboo salt.
So, what's the difference between different salts?
With these questions, let's take a look at what Li Hongyu, director of the Nutrition Department of Chengdu Second People's Hospital, said. How to choose the salt that suits you?
Dr. Li told us that although there are many kinds of salt, the main component is sodium chloride.
For example, on this basis, adjusting different iodine content becomes what we often say: non-iodized salt, iodized salt and low iodized salt. Different people have different needs for salt. Let's see how to choose the right salt:
iodized salt
Suitable: Pregnant women, lactating women and people who need iodine supplementation recommend iodine intake: 200 micrograms per day.
Dr. Li said that the fetus and infancy belong to the critical period of brain development, which requires high iodine and is very sensitive to iodine deficiency, which easily affects normal growth and development. Therefore, for women who want a baby, it is recommended to supplement iodine in advance during the preparation period, which can effectively prevent miscarriage, premature delivery and fetal malformation. Similarly, breast-feeding women should also supplement iodine in time to avoid affecting the baby's intellectual development and physical development. In addition, in the remote mountainous areas lacking seafood, the iodine content in food is relatively low, so it is recommended to eat iodized salt to maintain the normal needs of the body. Low iodized salt
Appropriate: recommended iodine intake for the general population: adult daily 150 micrograms; Children (3- 14 years old) 90- 120 micrograms per day; Baby (0- 12 months) 50 micrograms per day With the improvement of living standards, there are more and more seafood and more food. Most healthy people with normal constitution don't need to supplement iodine deliberately, but keep a diverse diet and balanced nutrition. Dr. Li told us that in developed areas, especially in coastal areas, seafood is rich in iodine, so people often take too much iodine invisibly. Long-term intake will lead to chronic exceeding the standard and increase the risk of thyroid diseases.
Therefore, this kind of people should pay special attention to the low iodine diet.
Non-iodized salt
Appropriate: Recommended iodine intake for some patients with thyroid diseases: 0 micrograms per day.
Patients with thyroid diseases should pay special attention to iodine intake.
Iodine excess is the cause of severe thyroid diseases, which can stimulate molecular growth and aggravate tumors. Seriously, it will also make the originally hidden thyroid self-excitation appear. Therefore, Dr. Li suggested that patients with thyroid diseases should follow the doctor's advice and choose a low iodine or iodine-free diet. In addition, Dr. Li also mentioned that the word "non-iodized salt" in non-iodized salt is generally on the packaging, which clearly indicates that there are not many in the market and it may be difficult to buy. At this time, ordinary salt can be poured into the pot and stir-fried for five minutes, and the iodine contained in it will volatilize a lot.
Low sodium salt
Suitable for: patients with hypertension
Excessive intake of sodium ions in salt will release a factor from adrenal gland and brain tissue, which will increase blood pressure, blood vessel wall pressure and cell edema, leading to a continuous decline in blood pressure. Therefore, Dr. Li suggested that patients with hypertension should pay attention to a low-salt and low-sodium diet, and try to control the daily salt intake below 3-4 grams, which is helpful to balance blood pressure.
salt-free diet
Suitable for patients with abnormal renal function.
Dr. Li stressed that patients with abnormal renal function should pay special attention to low sodium and potassium, strictly control potassium intake according to doctor's advice, and adopt a salt-free diet directly if necessary. Because too much sodium and potassium intake will accelerate kidney damage, resulting in urine can not be discharged, aggravating the condition.
Patients with uremia need to be more cautious. It is recommended to consult the competent doctor and nutritionist directly and make a reasonable diet according to the arrangement.
Dr. Li said that although no salt tastes fresh, we must pay attention to the intake of salt.
Because foods containing too much salt will reduce the viscosity of protective mucus in the stomach, so that its protective effect on the stomach wall will be reduced, and various harmful factors in food will more easily act on the stomach wall and promote the occurrence of gastric cancer. In addition, excessive salt intake will also lead to a large loss of calcium in our bodies, leading to "brittle bones", and the symptoms of osteoporosis in middle-aged and elderly people will be more obvious. Therefore, the salt intake not only varies from region to region, but also varies from person to person. The daily salt intake of healthy adults should not exceed 6 grams. Dr. Li made an analogy. A flat iron beer lid is just the salt intake needed by healthy adults in a day, which is about 5 to 6 grams. For some patients with chronic diseases, half a cover is generally enough.
Pay attention to these misunderstandings of salt.
Myth 1: Is sea salt more nutritious than well salt? Are all kinds of added salt more nutritious than ordinary salt?
Dr. Li said that the salt in our country is generally divided into two categories, namely well salt and sea salt. It's just that the origin is different, the nutrition is similar, and the iodine content of sea salt is relatively high. Dr. Li stressed that we should not think that it is good to contain all kinds of added salts. If the ingredients in salt are added too much, it is easy to cause electrolyte disorder and lose nutrition. Try to choose the salt produced by regular national manufacturers. Ordinary snowflake salt is enough to supplement a variety of minerals and is suitable for most ordinary people. In short, buy salt, only the right one, not the expensive one.
Myth 2: Can eating soy sauce without salt reduce salt intake?
Dr. Li told us that 5 ml of soy sauce is equivalent to 1 g of salt, which is more likely to lead to excessive salt intake.
Therefore, it is suggested that people with heavy taste should constantly strengthen their health concept, change their cooking and eating habits, reduce the amount of salt by measuring (quantitative salt spoon), eat less pickled food, and gradually cultivate a light taste.
In addition, chicken essence, lobster sauce and oyster sauce are all salty condiments, so don't mix them when cooking.
When is the best time to put salt in cooking?
Dr. Li told us that the nutrients contained in salt are easy to volatilize at high temperature. If the salt is put too early and volatilizes during cooking, the salty taste of the salt will be reduced. After cooking, people will think that the dishes are not salty and add salt again, which will easily lead to excessive salt intake. In addition, if the salt is put too early, the iodine inside will volatilize, which will also lead to the blackening of the vegetable water and affect the appearance of the vegetable. Therefore, it is recommended to put salt when the dish is almost cooked.
How to preserve salt?
Dr. Li said that iodized salt is easily oxidized and decomposed under the influence of heat, light and wind. In order to better retain the nutrients in table salt, it is suggested to keep it in ceramics and glass bottles and put it in a dry and dark place to avoid sun exposure and air moisture absorption.
Of course, it is also a good idea to eat while buying. Buy less at a time to avoid long-term storage. In short, salt is a good thing, but it can't be excessive; Iodine can be added, but it should be supplemented according to the crowd.