Sodium

What is Sodium?

Sodium is one of the most essential minerals for life. Along with chloride, they contribute to the maintenance of charge and concentration difference between cell membranes.

While sodium serves as the principal cation or the principal positively charged ion in extracellular fluid, potassium serves as the cation inside cells. The concentration of potassium inside the cells is about 30 times than that outside cells. However, the concentration of sodium is 10 times lower than outside cells.

Sodium and Hypertension

The intake of sodium is one factor that is involved in hypertension, a condition wherein high blood pressure has developed. Some people are known to be “salt sensitive” that they need to reduce their sodium consumption in order to reduce blood pressure levels, the condition of hypertension mostly occur as people age and can be developed over time.

Excessive consumption of this mineral early in life can possibly weaken the body’s genetic defense against the development of high blood pressure. It is best not to wait for the occurrence of hypertension, but necessary precautions such as reduced sodium intake should be observed while blood pressure is still normal, as this can help decrease the risk of having high blood pressure. Healthy eating, physical exercise, stress management, maintaining ideal body weight, and the amount of mono- and polyunsaturated fatty acids in every meal, are some of the essential factors to be considered. Eating foods that are good sources of potassium, magnesium, and calcium are strongly recommended as protective measures against hypertension.

An overall eating regimen known as Dietary Approaches to Stop Hypertension (DASH) and limiting the intake of sodium to 1500mg per day can be helpful in lowering blood pressure for those individuals who already have hypertension. The National Cancer Institute and the American Heart Association recommends that the DASH diet as it is lower in sodium, cholesterol, fat, and saturated fat; and higher in calcium, magnesium, and potassium than the typical American diet.

Sodium Absorption

The sodium absorption in the small intestine plays a significant role in the absorption of water, glucose, amino acids, and chloride. It has a vital part in keeping the cells water balance and in the function of both muscles and nerve impulses.

The kidneys excrete excess sodium from the body. Excessive intake of sodium can lead to water retention or edema. Women are at higher risk of developing osteoporosis even though they have sufficient intake of calcium, when they consume too much sodium. Studies have shown that for every teaspoon of consumed salt (2,000 mg of sodium), almost the same amount of calcium is excreted in the urine.

Sodium RDA

The Food and Nutrition Board of the Institute of Medicine created an adequate intake level (AI) sodium intake in 2004. Such recommended level of intake is well below than the average dietary intakes of most people in the United States.

AGE

SODIUM (g/day)

SALT (g/day)

0 to 6 months 0.12 0.30
7to 12 months 0.37 0.93
1 to 3 years 1.0 2.5
4 to 7 years 1.2 3.0
9 to 13 years 1.5 3.8
14 to 18 years 1.5 3.8
19 to 50 years 1.5 3.8
51 to 70 years 1.3 3.3
71 years and older 1.2 3.0
Pregnant 14 to 50 years 1.5 3.8
Lactating 14 to 50 years 1.5 3.8

 

Most of the intake of sodium and chloride comes from salt. About 75% of the total consumption of salt in the United States is derived from the added salt during the manufacturing or processing of food, rather than from the actual added salt during cooking or at the table.

Sodium Rich Foods

Some of the foods that are highly rich in sodium are beef hot dog, salted pretzels, potato chips, macaroni, canned tomato juice, whole wheat bread, white bread, ham, corned beef, canned chicken noodle soup, and cereals. Foods that have low sodium content include mango, pear, carrot, tomato, unsalted popcorn, olive oil, brown rice and orange juice.

References

WisconsinColorado State University; LPI; University of Massachusetts; NIH.