This blog post examines the physiological role salt plays in our bodies and the impact of excessive consumption on health in a balanced manner.
People say, “Food tastes good when it’s seasoned right.” In other words, the seasoning we perceive as delicious is achieved by adding just the right amount of salt. People don’t add salt because they like its salty taste; they add it because it enhances the overall flavor of the food. In cooking, salt plays a role far beyond being a simple seasoning. It not only balances the flavors of the dish but also acts as a catalyst, bringing out the inherent taste of the ingredients. This is precisely why many chefs say, “Salt is the key that awakens all flavors.” Therefore, proper salt usage is a crucial factor determining the quality of a dish.
Salt is not merely about enhancing food’s taste; it is an essential mineral for our bodies’ physiological functions. Consuming an adequate daily amount of salt is vital for maintaining life. This is because while humans can endure prolonged periods without food, they cannot survive long without salt and water. For instance, the fact that one can survive for several days on just water and salt in extreme situations, even without food, underscores salt’s vital importance.
So why does our body need salt? The chemical name for table salt is sodium chloride (NaCl), composed of 40% sodium and 60% chlorine. The sodium in table salt is essential for absorbing monosaccharides (a component of carbohydrates) and amino acids (a component of proteins) into the bloodstream. Therefore, if salt is not added to food, these vital nutrients—carbohydrates and proteins—cannot be properly absorbed into the blood and are ultimately excreted. This signifies that salt is not merely a seasoning but plays a crucial role in the body’s metabolic activities.
Most of the sodium we consume is absorbed through active transport in the small and large intestines. Nutrients like carbohydrates, proteins, and fats are broken down into glucose, amino acids, and fatty acids, respectively, and then absorbed in the small intestine due to the sodium concentration difference between intracellular and extracellular fluids. Sodium plays a particularly crucial role for glucose. Intestinal epithelial cells absorb sodium by utilizing the concentration gradient between the sodium ions in the small intestinal lumen and those within the intestinal cells. During this process, nutrients like glucose and amino acids bind to one part of a protein transporter with two binding sites, while sodium binds to the other part. They then move together through the cell membrane into the cell. This complex process clearly demonstrates how vital sodium absorption is for maintaining normal bodily functions.
If sodium is absent in the intestine, vital nutrients like glucose and amino acids present there cannot be absorbed into the bloodstream and are ultimately excreted from the body. The opposite is also true. That is, if sodium is sufficient in the intestine but nutrients like glucose or amino acids are lacking, sodium absorption does not occur properly. When sodium absorption is impaired, various diseases can occur. For example, diseases like cholera and dysentery cause vomiting and diarrhea, leading to rapid fluid loss. This reduces plasma volume and lowers blood pressure. In such cases, blood circulation becomes impaired, putting the body in a critical state.
Children, especially, can develop circulatory shock if they experience diarrhea during summer, and without prompt treatment, it can be fatal. To prevent fluid loss from diarrhea, maintaining consistent body fluid levels is crucial, which requires sufficient sodium absorption. When sodium is sufficiently absorbed in the intestines, blood osmotic pressure increases. This triggers an osmotic effect, causing water to move from the small intestine into the blood plasma, thereby increasing the water content in the plasma. Thus, sodium is not merely a nutrient but plays a vital role in maintaining the body’s physiological balance.
However, salt should be consumed in moderation to benefit health; excessive intake can lead to various health problems. The most well-known disease caused by excessive sodium intake is hypertension. Furthermore, excessively consumed sodium can contribute to cardiovascular disease and obesity. Consequently, experts recommend a daily sodium intake of 200mg to 1,000mg. Converted to salt quantity, this equates to approximately 0.5g to 2.5g. This amount can generally be sufficiently obtained through a variety of foods, meaning one should be cautious about excessive intake.
In Korean food culture, many dishes like soups, stews, noodles, and side dishes are high in sodium, making maintaining a low-sodium diet an important way to protect health. Especially fermented foods like kimchi and soy sauces have high sodium content, so consuming them in appropriate amounts is necessary for health. Recently, more households are using low-sodium kimchi or low-sodium soy sauce to reduce sodium intake, and the food service industry continues to develop low-sodium menu options. Consciously reducing sodium intake is crucial for health, and to achieve this, minimizing salt use and building a diet centered around natural foods is advisable.
