Sodium chloride — better known as salt — isn’t generally a nutrient you look for; it finds you. Used to flavor and preserve food as well as act as a stabilizer, salt is in almost everything we consume. The human body requires a small amount of sodium to operate normally, but Americans on average ingest way more than our bodies need. Additionally, older adults are particularly susceptible to sodium imbalances, thanks to decreased thirst mechanisms, renal function inhibitions, diuretic medications and fluid aversion (which is when people avoid drinking enough fluids in the hopes of decreasing the need for bathroom breaks).
So how much salt is enough, and how do you find the right balance?
Why We Need Salt
Our bodies require about 500mg of sodium daily to conduct nerve impulses, contract and relax muscles, and maintain the proper balance of water and minerals. We ingest sodium through our foods and drinks, process it via our kidneys, and then expel it through sweat and urine. This would be fine and dandy if we stuck to unprocessed foods like fruit, vegetables, whole grains, meats, and dairy foods, which are naturally low in sodium. However, according to the Harvard School of Public Health, most Americans consume at least 1.5 teaspoons of salt per day, which is about 3,400mg of sodium (at least six times more than we need).
Sodium deficiency, or hyponatremia, is rare in the States, but it does occur in older adults, particularly those living in long-term care facilities who take medications or have health conditions. Symptoms of hyponatremia can include: nausea, vomiting, headaches, confusion, lethargy, seizures, and coma.
…But Not Too Much
Hypernatremia, when too much sodium accumulates in the blood, is an acute condition typically affecting older adults who are mentally or physically impaired, overly dehydrated, or on diuretic medications. The accumulation of sodium in the blood causes cells to release water into the bloodstream seeking homeostasis, and the rapid shift of fluids can cause seizures, coma, or even death.
Overall, doctors are more concerned about the long-term effects of overconsumption rather than the rarer, acute imbalances. When we consume too much salt, the kidneys struggle to keep up with the sodium/water balance our bodies need. 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. This means more work for the heart, and more pressure on delicate blood vessels. Over time, the extra work and pressure can stiffen blood vessels, leading to high blood pressure, heart attack, and stroke.
In addition to cardiovascular disease, excessive sodium intake can lead to chronic kidney disease, stomach cancer, and osteoporosis.
Tips for Managing Your Sodium Intake
About 70% of our salt intake comes from commercially prepared foods. Avoiding all processed foods is way easier said than done, so here are some tips for lowering your sodium intake and managing a healthy nutritional balance.
- Prepare your own food as much as possible. We add far less salt at home than is added during commercial processes.
- Purchase fresh food instead of processed foods.
- Choose low- or no-salt snacks
- When cooking, replace the flavor of salt with sodium-free ingredients like herbs or seasonings.
- Read nutrition labels! Sodium content can vary across the same types of food by brand. (The CDC cites that a slice of frozen cheese pizza can have between 370 mg and 730 mg of sodium; a cheeseburger from a fast food restaurant can have between 710 mg and 1,690 mg!)
- Ask about low-sodium options at restaurants.
- Eat more potassium. Sodium and potassium are closely interconnected and play opposite roles in our body. Whereas high salt intake increases blood pressure, high potassium intake can help relax blood vessels and excrete sodium while decreasing blood pressure. (Check out this study showing that a higher sodium-potassium ratio is associated with significantly increased risk of cardiovascular disease and all causes of mortality, but those with higher potassium-sodium ratios show 20% better outcomes.) Fresh vegetables and fruits are naturally high in potassium and low in sodium.
Top 10 Sources of Sodium in American diets, according to the CDC:
- Breads or rolls
- Cold cuts/cured meats
- Burritos and tacos
- Savory snacks like chips, popcorn, pretzels, or crackers