Abstract: Salt and health - what’s the deal? Although there are a lot of negative health outcomes that can occur from excessive sodium intake, you do need sodium for your body to function properly. The average intake from the Western Diet - or the Standard US Diet - is about 2 times higher in sodium than the recommended intake. Excessive sodium during pregnancy can increase the risk of preeclampsia which is associated with many negative health outcomes for both mom and baby. That being said, your body requires a constant supply of sodium to conduct nerve impulses, balance your electrolytes, and maintain muscular function, therefore low sodium can be just as dangerous.
What Is Sodium And Why Do I Need It?
Chemically, typical table salt is sodium chloride, and sodium is the positively charged ion that makes up about 40% of its weight. Sodium plays a major role in our body's electrolyte balance, acid-base balance, and is essential for muscular contraction and nerve transmission.
In this article we will:
- Review sodiums role in pregnancy
- Introduce preeclampsia
- Introduce the biology of sodium metabolism in the body
- Explore supplementation recommendations regarding sodium and pregnancy
- Learn about the relationship between the food we eat and sodium
- Define recommended intake, toxicity, and deficiency
Sodium During Pregnancy
During pregnancy, your blood volume increases significantly in order to transport nutrients to the placenta and be sure both you and your baby are being nourished. Because of the increase in fluid throughout the body, the sodium levels in your blood typically decrease throughout pregnancy. Although high sodium intake is the most common concern, low intake can also be dangerous during pregnancy.
Having balanced electrolytes can support headaches, constipation, swelling of the limbs, and morning sickness. Excessive sodium intake can result in hypertensive disorders of pregnancy including preeclampsia and gestational hypertension.
One study conducted among 62,774 pregnant women found those with the highest sodium intake were 54% more likely to experience gestational hypertension and 20% more likely to experience preeclampsia compared to those with lower sodium intake.
What Is Preeclampsia?
Preeclampsia is a condition that involves both high blood pressure and elevated protein in the urine. It typically appears after 20 weeks of pregnancy and will disappear a few days after birth. It Is the leading cause of preterm birth and accounts for about 15% of infants who are growth restricted.
Not only does this condition influence birth outcomes, but also significantly affects the mother's health. This condition affects almost all of the mother's organs including the brain, heart, liver, and kidneys. If preeclampsia progresses, it can evolve into a more serious condition called eclampsia which could result in seizures or even death.
Sodium In Action: What Does It Do In The Body?
Your body has a wonderful ability to balance your blood sodium levels through a series of filtration systems, particularly within the kidneys. Although this means your body can regulate excessive amounts of sodium, in order to balance your electrolytes and Ph, the constant filtration of the kidneys with high intake can result in kidney stress or damage. This is because your body prioritizes the electrolyte balance, possibly at the cost of long-term kidney health. This means it is particularly important to balance sodium intake with water intake. This is because your kidneys are only able to excrete excess salt out through the urine if there is enough water to carry it out.
Your body has a special filtration system called The renin-angiotensin-aldosterone system (RAAS). This system is responsible for regulating blood pressure and sodium absorption and excretion from the kidneys. When there is a large amount of sodium that is being sent to the kidney cells to be filtered, the cells pull in the sodium, causing the cells to contact. When the cells are contracting the veins get smaller and tighter, resulting in vasoconstriction and eventually hypertension. This decreases the blood flow throughout the body, decreasing the movement of nutrients and filtration.
Is Sodium In Common Prenatal Vitamins?
Since sodium is found so abundant in the diet, supplementation is not necessary, nor is it recommended during pregnancy. It is more likely that you are in excess of sodium, than in need of extra. The only circumstances you may need to check your sodium levels are if you are malnourished, have a chronic illness that affects the kidneys, or experience extreme water loss due to dehydration, extreme sweating, vomiting, or diarrhea.
Eating Sodium During Pregnancy: Best Low Salt Snacks For Pregnancy
Only a small portion of the United States' sodium intake comes from table salt and at-home cooking. Many ready-to-eat foods such as TV dinners, frozen pizza, delicious meats, and even many pre-made dressings and sauces are extremely high in sodium. The biggest culprit of high sodium intake is from dining out!
This is part of the reason why, when possible, it is best to make these items on your own. If you are not able to, it is a good practice to learn to read nutrition labels. Sodium is required to be listed on a nutrition label including at restaurants with 20 locations or more.
5 Best low-salt snacks for pregnancy:
- Homemade fruit and yogurt parfait (plain yogurt, berries, topped with nuts and seeds)
- Homemade bean dip and veggie sticks (hummus, black bean dip, red bean dip)
- Apples or celery and peanut butter or other nut butter
- Yogurt dip with whole-grain crackers
- Guacamole and pita bread or veggie sticks
Balance is key! It is not necessary to never eat a frozen pizza again, learn moderation, and listen to your body's needs.
Dietary Guidelines for Americans, 2022-2025:
How Much Sodium Should I Take And How Much Is Too Much?
Throughout this article, we have explained the need for sodium in the diet, and the harm that having too much sodium can cause the body. A Daily Recommended Intake (DRI) for sodium adequacy, Adequate Intake (AI), has been set at 1500 mg for all healthy adults, women, pregnant, and lactating.
The American Heart Association and Chronic Diseases Risk Reduction levels defined by national academies recommended a maximum intake of 2300 mg/day. Most Americans consume an average of 3,393 mg of sodium per day which is well above the recommended intake, and even well above the maximum recommendation!
Did you know? One plate of the Applebee’s chicken nachos has almost 3.5 times (4980 mg) the amount of recommended sodium you need for the entire day?!
What Happens If I Don’t Have Enough Sodium?
A deficiency of sodium is very rare as most foods we eat, particularly in the traditional American diet, are high in sodium. However, a deficiency of sodium is quite harmful. Inadequate intake can lead to a condition known as hyponatremia. This condition is can be caused by a variety of medical problems, excessive energy expenditure, or excessive plain water intake.
Symptoms of hyponatremia include:
- Dizziness and confusion
Some extreme athletes are at risk for hyponatremia due to the large amounts of water lost through sweat. In such extreme physical activity events, it is important that athletes intake more than just plain water, such as using gels, eating pretzels, or consuming sports drinks throughout to provide adequate sodium for electrolyte balance. Other conditions that are associated with severe dehydration such as excessive vomiting or diarrhea also increase the risk of hyponatremia.
Conditions that influence your body’s filtration system, such as diseases that affect your kidneys, liver, or heart, can increase the risk of hyponatremia. Finally, those who take certain medications such as diuretics are at increased risk.
Although there are a lot of negative health outcomes that can occur from excessive sodium intake, you do need sodium for your body to function properly. It is common for most Americans to intake too much sodium, mainly due to processing, manufacturing, and eating out.
Excessive sodium during pregnancy can increase the risk of preeclampsia which is associated with many negative health outcomes for both mom and baby. That being said, your body requires a constant supply of sodium to conduct nerve impulses, balance your electrolytes, and maintain muscular function, therefore low sodium can be just as dangerous.
Learning moderation with high sodium foods is a good practice to reduce overall sodium intake. Additionally, learning to read food labels will help you make informed decisions about your dietary choices.
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- Avanelle Kirksey, Ruth L. Pike, Jacqueline A. Callahan, Some Effects of High and Low Sodium Intakes during Pregnancy in the Rat: II. Electrolyte Concentrations of Maternal Plasma, Muscle, Bone and Brain and of Placenta, Amniotic Fluid, Fetal Plasma and Total Fetus in Normal Pregnancy, The Journal of Nutrition, Volume 77, Issue 1, May 1962, Pages 43–51, https://doi.org/10.1093/jn/77.1.43
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