Eating less salt could reduce blood volume… Who should be careful?

For health-conscious people, sodium is like a "public enemy." This is because people frequently hear advice to "reduce sodium intake to prevent high blood pressure." Consequently, some people practice eating bland food unconditionally. However, consuming only a low-salt diet without considering one's own physical condition can actually harm one's health.

Sodium plays a role in helping to eliminate waste products and regulating body fluid volume. A certain amount of sodium is essential for the body. For a body weight of 60 kg, the sodium content in the body should be 70 to 80 g.

If the sodium concentration is lower than this, various problems such as fatigue, loss of appetite, and lethargy occur. An example is people who feel dizzy or become exhausted when they sweat profusely. This is a problem that arises as the body's sodium concentration drops rapidly while sweating.

An excessively low-salt diet can be harmful, especially for people with heart problems. If sodium intake decreases sharply, fluid volume is not properly regulated, leading to a decrease in blood volume. If blood volume further declines while the heart's contractile function is impaired, blood cannot be smoothly supplied to the entire body, which can lead to serious illnesses.

In fact, there is a study by a research team at McMaster University in Canada showing that the higher the amount of sodium excreted from the body, the higher the incidence of myocardial infarction and stroke in heart disease patients. According to the study, heart disease patients with a daily sodium excretion of 8g or more had incidence rates of myocardial infarction and stroke of 6.8% and 6.6%, respectively, which were higher than those with less than 2g (5.1% and 4.9%).

Of course, the statement that moderate sodium intake is necessary should not be misunderstood as meaning that it is okay to eat salty food as you do now. It is true that Koreans need to slightly reduce their sodium intake. The daily sodium intake recommended by the World Health Organization (WHO) is 2,000 mg. According to the Korea Disease Control and Prevention Agency's "National Health Statistics," as of 2021, the average sodium intake of Koreans reached 3,080 mg, which is about 1,000 mg more than this amount.