Most people consume too much salt, and a University of Iowa researcher has discovered a potential reason for this habit: it helps our mood better.
UI-based psychologist Kim Jonhson and colleagues found that when mice lack sodium chloride, common salt tablets, they rarely participate in favorite activities, such as drinking sugar or pressing a stimulating bar. pleasure in the brain.
Johnson said: 'The usual pleasant things for rats are not as interesting as usual, suggesting that the lack of salt and the accompanying cravings are one of the most important symptoms associated with depression'. .
UI researchers do not think it is a form of depressive depression because there are many other factors that need to be discussed, but the interest in normal activities is one of the most important traits in mental depression. physical. And the idea that salt is a natural substance that improves mood can explain why we often use too much salt, although it causes high blood pressure, cardiovascular disease and other health problems.
Previous research has shown that average salt consumption per capita is 10 grams per day, 4 grams higher than the amount recommended by the US Food and Drug Administration, and may exceed Body salt needs 8 grams. Jonhson, a physiologist at the School of Liberal Arts and Sciences, and Pharmacology - Carver Medical University, published a report of these findings in the June issue of Physiology & Behavior, along with Other authors are Michael J. Morris and Elisa S. Na, graduate students at the UI. The authors also commented on other studies on the reasons for high salt consumption.
The concentration of salt in everything from pastries to pasta today is very high, but in the past, salt was very rare. The consumption of salt as well as its price increased sharply around 2000 BC, when it was discovered as a food preservative. Roman fighters are paid with salt, the word 'salary' comes from the Latin salt. Even when cooling technology reduces the demand for salt in the 19th century, salt consumption is still high because people like the salt and spices also become quite cheap. Today, 77% of the salt we consume comes from processed foods and restaurants.
Evolution can play an important role in people's salt use habits. Humans evolved from salty creatures. When living on land, the body continues to need sodium colrua because minerals play a crucial role in allowing liquids to and from the cell, as well as helping neurons to transmit information through the brain and body. . But when people evolved in the hot climate of Africa, sweating reduced the body's sodium.Salt is very rare because our ancestors have a diet rich in vegetables and living far from the sea.
Johnson said: 'Most of our biological systems need sodium to be able to move smoothly, but since the species has no access to sodium, our kidneys have evolved into' savers. salt''.
Behavior also plays an important role in ensuring enough salt for the body. Animals like us have a taste system designed to detect salt and the brain can remember the location of salt sources - such as where there is salt in the pasture. The mechanism of drilling in the brain will be activated when we consume salt.
The body needs salt and knows how to find it and how to preserve it. But now scientists find evidence that salt is an addictive substance - almost like opium.
The first sign is to use a substance even when it is known to be harmful. Many people are required to reduce sodium intake due to health problems, but they are unlikely to do so because they like the salt taste and try to find low-salt foods.
Another sign of addiction is an intense craving for when not in use. Johnson and colleagues' experiments showed similar changes in brain activity when mice lacked salt or opium.
Joannson concluded: 'This shows that the need for salt and craving is related to the same mechanism as abuse and opium addiction'.
Refer:
Morris, MJ;Na, ES;Johnson, AK Salt craving: The psychobiology of pathogenic sodium intake.Physiology & Behavior, 94 (5), p.709-721, Aug 2008, 2008;94 (5): 709-721 DOI: 10.1016 / j.physbeh.2008.04.008