Two major effects of salt on human body
Salt dissociates into sodium ions and chloride ions in water.
On the tongue, sodium ions stimulate corresponding nerve signals through specific "sodium ion channels" and transmit them to the brain, where they are analyzed as salty. This is its contribution to taste.
Sodium ions are absorbed into blood, which is called a part of electrolyte in blood. Life activities are composed of substance transport and biochemical reactions in the body, and proper electrolyte concentration is the basis of normal biochemical reactions. This is the contribution of salt to life-sustaining activities.
How much salt does the human body need?
In order to realize the two functions of salt, the amount of salt needed by human body is different.
From the point of view of satisfying electrolyte balance, it is generally considered that 1500 mg sodium per day is enough for adults. Converted into salt, it only needs 3.8 grams.
"Proper salinity" is very important to the taste of food. In real life, different people have different standards for "appropriate salinity". Some people like "heavy mouth", others like "light mouth". But for people with light diet, 3.8 grams of salt is not enough.
Therefore, no one is worried about "insufficient salt intake", and they all consider "whether it is excessive".
When the intake of salt is too high, it will cause chronic harm to the human body-for example, a high-salt diet will increase the risk of hypertension, which has been confirmed by a large number of scientific data. From a health point of view, dietary guidelines suggest that adults should not consume more than 2300 mg of sodium per day, which is roughly equivalent to 6 grams of salt. If it is a patient with hypertension, it is recommended to control it below 4.5 grams.
"Reducing salt" is because reality has eaten too much.
For the flavor of food, 6 grams of salt is too little, and the survey data in China is above 10 grams per day on average. Therefore, "reducing salt" has become one of the basic principles of healthy diet in the whole society.
But reducing salt is not easy.
Food will eventually be eaten by consumers. "Delicious" is the primary demand of most people for food-even those who want to be "healthy" intellectually still indulge their taste buds when choosing food.
In the formulation design of food, we will explore the relationship between salt content and flavor, and the result is basically-when the salty taste is obviously reduced, consumers don't like the product.
Many "experts" recommend the use of "salt-limited spoons" to reduce the amount of salt used in cooking, and many people buy salt-limited spoons in the kitchen. But in practice, I found that the food added with salt according to the salt-limiting spoon was too weak, so I chose to quit the salt-limiting spoon.
There are many "sugar substitutes", why not "salt substitutes"
Sugar is also very harmful to health, so there are various "sugar substitutes" or "sweeteners".
For salty taste, there is no successful "salty agent" or "salt substitute" so far.
This is because the sweetness receptor on the tongue can combine with many molecules other than sugar to produce sweetness. Salty taste is produced by sodium ion through a specific channel-it seems difficult to let other ions pass through the sodium ion channel. In the periodic table of elements, the neighbors of sodium are lithium and potassium. Lithium is indeed salty, but it is toxic and expensive, so it can't be used as a substitute for salt. Potassium also has a certain salinity-1g potassium chloride is equivalent to the salinity produced by 0.6 g salt, which makes it possible to replace part of salt and reduce sodium intake. This is the concept of "low sodium salt". Ordinary low-sodium salt contains 65% sodium chloride and 25% potassium chloride, the salinity is equivalent to 80% of ordinary salt, and the sodium content is about 65% of ordinary salt. Generally speaking, low sodium salt is helpful to "reduce salt".
But when the dosage of potassium chloride is large, it will be bitter. In addition, patients with kidney disease should not consume too much potassium. Therefore, potassium chloride cannot meet the demand of "replacing salt".
It is feasible to reduce salt by "salting out"
Salty taste is produced by sodium ions, but the process of human body "perceiving salty taste" will be influenced by other tastes.
With the same amount of salt, you can make the salty taste stronger through other flavors-or you don't need so much salt to reach a pleasant salinity.
The most typical "curing agents" are monosodium glutamate and chicken essence. Their ingredients are glutamate and odorous nucleotide salts, and their umami taste can greatly increase the perceived salty taste. Many people, including many nutrition experts, think that monosodium glutamate and chicken essence also contain sodium, so it is a complete misunderstanding to regard them as the source of "invisible salt" and say that it should be used less or not to reduce salt.
In addition to the unexpected taste, spicy, sweet and sour taste also enhances the salty taste to some extent-or reduces people's demand for salty taste.
Getting used to light taste is the key.
"Heavy mouth" and "light mouth" are both subjective experiences, in order to obtain sensory pleasure and satisfaction. What kind of salinity makes you feel happy can be gradually changed. When we continue to eat salty food, we will like salty food; On the contrary, if we gradually reduce the salinity of food, we will feel happy under a more "light" taste.