By T. Jared Bunch, MD
Published Aug 19, 2014
We all have heard about sodium. Sodium and chloride are the primary components of salt. Often when I talk to my patients about lifestyle changes that they can make to improve their heart health; the first thing I am told is they have stopped adding salt to their meals. In this sense, most of us have in our minds that too much salt is a bad thing for our health.
In Western cultures salt is in almost all of our food sources. We use if for taste, as a preservative, and also for texture. When people get serious about lowering their salt, they are often amazed at how much they consume. Look on nutrition labels for all your food sources. Salt will be listed by serving. Make sure you also look at the label if you drink soda, including diet drinks, as well as coffee and tea.
We all need salt in our diets. Salt helps us maintain our blood pressure, keep our cells healthy, and allows our body to conduct electrical signals in our heart, gastrointestinal tract, and nervous system. Unfortunately we often get too much. The Dietary Guidelines for Americans recommend limiting sodium to less than 2,300 mg a day. If you are older than 51, black, or have high blood pressure, diabetes, or kidney disease your diet should have less than 1,500 mg.
What Is Sodium Sensitivity?
This is the elevated blood pressure response with salt intake. It is quite variable in each of us. The variations are driven by our genetics and age. Unfortunately, salt sensitivity increases with age and this is what drives the recommendation to lower your daily salt after the age of 50. Also, people who are obese, black, have metabolic syndrome, or chronic kidney disease have higher rates of salt sensitivity, the DASH-sodium clinical trial showed.
Sodium Intake and High Blood Pressure Risk
High blood pressure (primary hypertension) is often of reflection of where we live. It is seen frequently in societies that on average consume 2.3 grams of sodium a day or more. But it is almost never seen in societies than consume less than 1.2 grams of sodium a day, studies show. In addition, when people who live in low sodium societies migrate to high sodium societies, they often develop high blood pressure. These observations provide powerful insight into the role of lifestyle and dietary choices on our health. By lowering your sodium by 1.0 gram per day for 4 weeks a study of patients with high blood pressure showed that you could typically lower your blood pressure by 5/3 mmHg. In addition, many of the commonly used blood pressure medications are more potent or effective when used in combination with salt restriction.
Why is it important to worry about blood pressure, even early in life, and even you are a very active athlete? High blood pressure is a very common cause of atrial fibrillation, heart failure, coronary artery disease, stroke, dementia, and kidney disease. If you consider all of these disease states, it accounts for most of the common reasons we die.
Sodium as a Cause of Cardiac-related Death
In a new article, Dr. Mozaffarian and colleagues from Tufts University examined the role of global sodium consumption and cardiovascular death, published in the New England Journal of Medicine. They performed dietary surveys in 66 countries.
With these surveys they reported amazing findings.
Global average sodium consumption per day was 3.95 gm. This is nearly 2 times greater than the recommended amount, and nearly 3 times greater than the recommended amount in people over 50 or those with other diseases.
Women on average consumed less salt per day than men (3.77 gm versus 4.14 gm).
People over 70 consumed more salt than younger people on a daily basis (4.07 gm versus 3.97 gm).
The greater your income, the more salt you ate. The highest incomes consumed 3.88 gm per day compared to the lowest incomes that consumed 2.91 gm per day.
The study highlights several important items. First, we consume way too much salt globally. Second, people who may be at the highest risk of high blood pressure from salt, due to salt sensitivity, consumed more than those people at lower risk.
What Are the Consequences of Salt Consumption?
The most sobering details of the study from Tufts University were the global consequences of too much salt consumption. The group estimated that 1.65 million deaths from heart causes were attributed to high sodium intake. These deaths account for approximately 1 of every 10 deaths related to the heart. Of these deaths 4 of 5 were in lower income countries and 40 percent were before the age of 70. In general, the highest death rates were seen in Central Asia, Eastern and Central Europe followed by East Asia and Southeast Asia. The country with the highest death rates attributed to sodium was Georgia.
How to Prevent Cardiovascular Complications and Death from Sodium Intake
The Mayo Clinic has an excellent resource to follow to lower your salt intake.
Recommended steps include:
Eat more fresh foods (remember salt is preservative and frequently is added to processed food products).
Choose “low” sodium products.
Remove salt from recipes when possible and always from your table when you eat.
Minimize the use of condiments that are often sodium rich (soy sauce, salad dressing, ketchup, mustard, relish, and sauces/dips).
Replace salt with herbs and other spices to improve salt (do not substitute with sea salt as this contains the same amount of sodium as typical salt).
Learn how to read nutritional labels.
Sodium-free or salt-free: < 5 mg of sodium/serving. Very low sodium: <35 mg of sodium/serving Low sodium: <140 mg of sodium/serving Reduced or less sodium: At least 25 percent less sodium than the regular version Lite or light in sodium. At least 50 percent less sodium than the regular version Unsalted or no salt added. No salt is added during processing of a food, but the food source itself may contain sodium. Don’t forget your breads. Bread often contains a lot of sodium. I often see people buy whole grain or multigrain bread as a healthy food choice. Again, be careful to read the back label to see how much sodium per slice is in the bread. It can be up to 100 mg/slice.