Sodium, one of the seven major minerals, is essential for health

Sodium is the chemical element with the symbol Na from Latin natrium. Sodium is the sixth most abundant element in the Earth's crust and exists in numerous minerals such as feldspars, sodalite, and halite (NaCl). Many salts of sodium are highly water-soluble: sodium ions have been leached by the action of water from the Earth's minerals over eons, and thus sodium and chlorine are the most common dissolved elements by weight in the oceans.

Sodium is a type of metal that is always found as a salt. The most common dietary form is sodium chloride. Sodium chloride is commonly called table salt.

Salt and Sodium
Salt, also known as Sodium Chloride, is about 40% sodium and 60% chloride. It flavors food and is used as a binder and stabilizer. Salt is also a food preservative because bacteria cannot grow in the presence of high levels of salt. Therefore, salt is also often used for cleaning and disinfecting.

In fact, many people use the words "Sodium" and "Salt" interchangeably, but they are different. Sodium is a naturally occurring mineral and nutrient. Unprocessed foods such as fresh vegetables, Legumes and fruits may naturally contain sodium. Baking soda also contains sodium. Sodium helps balance the amount of fluid and electrolytes in the body. This balance can affect blood pressure and health. Kidney and heart health.

How much sodium does the body need?
The U.S Dietary guidelines recommend that Americans consume less than 2,300mg (milligrams) of sodium per day.

Every day, our bodies receive about 75% to 90% of sodium from salt added to foods. The human body needs small amounts of sodium to conduct nerve impulses, contract and relax muscles, and maintain the proper balance of water and minerals. Too much sodium in the diet can lead to high blood pressure, heart disease and stroke.

Guidelines for adequate intakes (AI) of sodium were established based on the lowest levels of sodium intake used in randomized controlled trials that did not show a deficiency but that also allowed for an adequate intake of nutritious foods naturally containing sodium. For men and women 14 years of age and older and pregnant women, the AI is 1,500mg per day.

A Chronic Disease Risk Reduction (CDRR) Intake has also been established, based on the evidence of benefit of a reduced sodium intake on the risk of cardiovascular disease and high blood pressure. Reducing sodium intakes below the CDRR is expected to lower the risk of chronic disease in the general healthy population. The CDRR lists 2,300 milligrams a day as the maximum amount to consume for chronic disease reduction for men and women 14 years of age and older and pregnant women. Most people in the U.S. consume more sodium than the AI or CDRR guidelines.

According to the CDC, most people in the United States consume an average of more than 3,400 mg of sodium per day, more than the AI or CDRR guidelines.

How much salt should you eat?
Although salt and sodium are different, but salt has 40% sodium and we get most of sodium from salt. Many companies and restaurants use salt to preserve, season and flavor their dishes. And, in one teaspoon of salt contains about 2,300mg of sodium, it's easy to exceed the daily value .
You can limit your sodium intake by eating unprocessed foods. You may also find it easier to manage your sodium intake by cooking more meals at home.

Amount of sodium in salt:
Finely ground salt is dense, so it usually contains more sodium than coarser salt. The approximate amount of sodium in a teaspoon of each type of salt as follows:

- Fine iodized table salt: 2,300mg
- Coarse kosher salt: 1,920mg
- Fine kosher salt: 1,120mg
- Fine sea salt: 2,120mg
- Raw sea salt: 1,560 mg
- Pink salt (Himalayan): 2,200mg
- Black salt: 1,150-2,200 mg
- Fleur de sel: 1,560-2,320 mg
- Potassium salt (salt substitute): 0 mg (contains 2,760-3,180mg Potassium).

Sources of sodium in foods
Sodium isn’t generally a nutrient that you need to look for; it finds you. Almost any unprocessed food like fruits, vegetables, whole grains, nuts, meats, and dairy foods is low in sodium. Most of the salt in our diets comes from commercially prepared foods, not from salt added to cooking at home or even from salt added at the table before eating.

According to The Centers for Disease Control and Prevention, the top 10 sources of sodium in our diets include: breads or rolls, pizza; sandwiches; cold cuts or cured meats; soups; burritos, tacos; savory snacks like as chips, popcorn, pretzels, crackers; chicken; cheese; eggs, omelets.

Low sodium diet
Your doctor will recommend that you follow a low-sodium diet if you are at risk for high blood pressure or cardiovascular disease. In this case, you should consume less than 2,000 mg of sodium per day, although the American Heart Association (AHA) recommends keeping it below 1,500 mg. You should eliminate processed foods like hot dogs and pre-made meals. Thus, you can maintain this number more easily.

Sodium and Health
In most people, the kidneys have trouble keeping up with excess sodium in the blood. As sodium accumulates, the body holds onto water to dilute the sodium. This increases both the amount of fluid surrounding cells and the volume of blood in the bloodstream. Increased blood volume means more work for the heart and more pressure on blood vessels. Over time, the extra work and pressure can stiffen blood vessels, leading to high blood pressure, heart attack, and stroke. It can also lead to heart failure. There is some evidence that too much salt can damage the heart, aorta, and kidneys without increasing blood pressure, and that it may be bad for bones, too. Learn more about the health risks and disease related to salt and sodium:

1. Chronic kidney disease
Chronic kidney disease (CKD) shares risk factors with cardiovascular disease, with high blood pressure being a major risk factor for both. Salt sensitivity is reported to be more prevalent in patients with CKD due to a reduced ability to excrete sodium, which may lead to increased blood pressure.

Although there is evidence that links high sodium intake with high blood pressure, there is not adequate evidence that a low sodium restriction protects against or causes better outcomes of CKD than a moderate sodium restriction. One systematic review of patients diagnosed with CKD found that high sodium intakes of greater than 4,600mg a day were associated with progression of CKD, but low sodium intakes less than 2,300 mg a day had no significant effect when compared with moderate sodium intakes of 2,300-4,600mg a day.

Guidelines generally advise a moderate rather than low sodium restriction to prevent the development and progression of CKD. A daily sodium intake of less than 4,000 mg is recommended for overall management of CKD, and less than 3,000 mg daily for CKD with symptoms of fluid retention or proteinuria, a condition in which excess protein is excreted in the urine.

2. Osteoporosis
The amount of calcium that your body loses via urination increases with the amount of salt you eat. If calcium is in short supply in the blood, it can leach out of bones. So a diet high in sodium could have an additional unwanted effect—the bone-thinning disease known as osteoporosis. A study in post-menopausal women showed that the loss of hip bone density over two years was related to the 24-hour urinary sodium excretion at the start of the study, and that the connection with bone loss was as strong as that for calcium intake. Other studies have shown that reducing salt intake causes a positive calcium balance, suggesting that reducing salt intake could slow the loss of calcium from bone that occurs with aging.

3. Cancer
Research shows that a higher intake of salt, sodium, or salty foods is linked to an increase in stomach cancer. The World Cancer Research Fund and American Institute for Cancer Research concluded that salt, as well as salted and salty foods, are a “probable cause of stomach cancer.”

4. Cardiovascular disease
After conducting a review on sodium research, the Institute of Medicine concluded that reducing sodium intake lowers blood pressure, but evidence of a decreased risk of cardiovascular diseases (CVD) is inconclusive. It is clear, however, that high blood pressure is a leading cause of CVD. It accounts for two-thirds of all strokes and half of heart disease. In China, high blood pressure is the leading cause of preventable death, responsible for more than one million deaths a year.

There may be a genetic component to salt intake, as people respond differently to lower sodium intakes. Those who are “salt-sensitive” experience the greatest blood pressure reductions after following a reduced sodium diet. Those who are “salt-resistant” do not experience these changes even with significant increases in sodium intake. Studies have found that women more than men, people older than 50 years, African-Americans, and those with a higher starting blood pressure respond the greatest to reduced sodium intake. However, there is not enough evidence to make strong conclusions about specific groups who may be salt-resistant; the overall evidence supports a benefit of limiting sodium intake for everyone, even though the optimal target amount is not clear.

Observational and clinical research has found that higher sodium intakes are associated with cardiovascular diseases and related deaths. The following are key studies:

4.1. Intersalt: Researchers measured the amount of sodium excreted over a 24-hour period (a good stand-in for salt intake) among more than 10,000 adults from 32 countries. The average was nearly 4,000 mg of sodium a day. Yet the range was huge, from 200 mg a day among the Yanomamo people of Brazil to 10,300 mg in northern Japan. Populations with higher salt consumption had higher average blood pressures and greater increases of blood pressures with age. Four groups of people—the four countries with salt intakes less than 1,300 mg per day—had low average blood pressures and little or no upward trend of blood pressure with age.
The authors conducted a re-review and update on the Intersalt data. They found: 1) a stronger association than their prior study with higher sodium intakes and higher blood pressure, and 2) a stronger association with higher sodium intakes and higher blood pressure in middle age participants as compared with younger adults.

4.2. TOHP: The two Trials of Hypertension Prevention (TOHP) were conducted from 1987-1995. [9,10] They tested the impact of lifestyle changes on blood pressure, such as weight loss, stress management, nutritional supplements, and consuming less sodium. In each of the studies, small decreases in blood pressure were seen with sodium reduction over 18-36 months. Years after the trials had ended, the researchers surveyed the participants and found that:
- After an average of 10-15 years, the TOHP participants in the sodium-reduction groups were 25% less likely to have had a heart attack or stroke, to have needed a procedure to open or bypass a cholesterol-clogged coronary artery, or to have died of cardiovascular disease.

- The higher the ratio of potassium to sodium in a participant’s diet, the lower the chances were of developing cardiovascular trouble. This suggests that a strategy that includes both increasing potassium and lowering sodium may be the most effective way to fight high blood pressure.

4.3. TOHP Follow-up Study: A continuation of the two previous TOHP trials in 2000 that looked specifically at CVD or deaths from CVD. When participants with sodium intakes less than 2,300 mg daily were compared with those who had intakes of 3,600-4,800 mg, there was a 32% lower risk of developing CVD. There was also a continuing decrease in CVD-related events (stroke, heart attack) with decreasing sodium intakes as low as 1,500 mg daily.
4.4. DASH: The Dietary Approaches to Stop Hypertension (DASH) trials, begun in 1994, were major advances in blood pressure research, demonstrating the links between diet and blood pressure.
- In the first study, 459 participants were randomly assigned to either 1) a standard American diet high in red meat and sugars, and low in fiber, 2) a similar diet that was richer in fruits and vegetables, or 3) the “DASH diet,” which emphasized fruits, vegetables and low-fat dairy foods, and limited red meat, saturated fats, and sweets. After eight weeks, the fruits and vegetables diet and DASH diet reduced systolic (the top number of a blood pressure reading) and diastolic (the bottom number of a blood pressure reading) blood pressure, with the DASH diet producing a stronger effect.

- The second study found that lowering sodium in either the DASH or standard American diet had an even stronger impact on reducing blood pressure. The DASH study contributed much of the scientific basis for the Dietary Guidelines for Americans 2010, which recommends reducing daily sodium to less than a teaspoon.

4.5. A meta-analysis of clinical trials found that a moderate sodium reduction to about 4,000 mg a day for at least one month caused significant reductions in blood pressure in individuals with both normal and high blood pressure. Further analysis showed that blood pressure was reduced in both men and women and white and black races, suggesting a benefit for the total population.
Assessing people’s sodium intakes can be tricky, and the most accurate method known is to measure 24-urine samples over several days. This is the method Harvard researchers used when pooling data from 10,709 generally healthy adults from six prospective cohorts including the Nurses Health Studies I and II, the Health Professionals Follow-up Study, the Prevention of Renal and Vascular End-Stage Disease study, and the Trials of Hypertension Prevention Follow-up studies. They looked at both sodium and potassium intakes in relation to cardiovascular disease (CVD) risk (as noted by a heart attack, stroke, or procedure or surgery needed to repair heart damage), and measured two or more urine samples per participant. After controlling for CVD risk factors, they found that a higher sodium intake was associated with higher CVD risk. For every 1,000 mg increase of urinary sodium per day, there was an 18% increased risk of CVD. But for every 1,000 mg increase of potassium, there was an 18% lower risk of CVD. They also found that a higher sodium-to-potassium ratio was associated with higher CVD risk, that is, eating a higher proportion of salty foods to potassium-rich foods such as fruits, vegetables, legumes, and low-fat dairy.

Signs of Deficiency and Toxicity
1. DeficiencyA deficiency of sodium in the U.S. is rare because it is so commonly added to a wide variety of foods and occurs naturally in some foods. Hyponatremia is the term used to describe abnormally low amounts of sodium in the blood. This occurs mainly in older adults, particularly those living in long-term care facilities or hospitals who take medications or have health conditions that deplete the body of sodium, leading to hyponatremia. Excess vomiting, diarrhea, and sweating can also cause hyponatremia if salt is lost in these fluids that are expelled from the body. Sometimes too much fluid abnormally collecting in the body can lead to hyponatremia, which might stem from diseases such as heart failure or liver cirrhosis. In rare cases, simply drinking too much fluid can lead to hyponatremia if the kidneys can’t excrete the excess water. Symptoms of hyponatremia can include: nausea, vomiting, headaches, altered mental state/confusion, lethargy, seizures, coma.

2. ToxicityToo much sodium in the blood is called hypernatremia. This acute condition can happen in older adults who are mentally and physically impaired who do not eat or drink enough, or who are sick with a high fever, vomiting, or infection that causes severe dehydration. Excessive sweating or diuretic medications that deplete the body of water are other causes. When sodium accumulates in the blood, water is transferred out of cells and into the blood to dilute it. This fluid shift and a build-up of fluid in the brain can cause seizures, coma, or even death. Extra fluid collecting in the lungs can cause difficulty breathing. Other symptoms of hypernatremia can include: nausea, vomiting, weakness, loss of appetite, intense thirst, confusion, kidney damage.

Compiled and penned by Crocus Media