You have probably heard that too much salt “is not good for you”. But how much salt is too much? What health problems are caused by too much salt? Let’s look to the most recent research to answer these important questions. Also, be sure to check out the accompanying post, How to reduce salt in your diet.
Is salt really a problem?
It sure is. Americans eat on average 3400mg of sodium (salt) every day which is ~ 1.5 times the amount recommended for health and disease prevention. Children aged 6-16 years consume on average 3300mg every day. The 2015-202 Dietary Guidelines recommends 2300mg per day. This is equal to approximately one teaspoon of regular table salt.
The message is clear. Americans eat way too much salt and are suffering as a result.
How much salt should you get each day?
The Tolerable Upper Limit (UL) which is the maximum amount of salt daily intake that is not likely to cause health problems is not established. Experts suggest a maximum level between 1400 and 2300mg per day for men and women over 14 yrs. As stated above this is equal to just under one teaspoon daily. As you will learning the accompanying post, salt is hidden in so many foods especially processed and fast foods that have become staples of the average American diet.
How does salt cause problems in the body?
Do you ever notice that your hands are puffy or feel swollen, or notice that you are especially thirsty after eating a high salt meal? Our kidneys serve as a filter to regulate the amount of salt (sodium) in our body and keep levels within a specific range for healthy cell activity- getting rid of salt when there is too much and holding onto salt when there is too little. With a diet high in salt, the kidneys have trouble keeping up and sodium accumulates. The body reacts to too much sodium in the blood and tissues, by retaining water (done by the kidneys) and increasing water by increasing thirst and your drive to drink. This “dilutes” sodium and reduces the concentration to a normal range required for cell activity. You feel this as an increased thirst and drive to drink water and as swelling. Swelling is most commonly in your feet and hands because gravity allows fluid to pool in these areas of your body.
Too much salt, then, means an increase in the volume of blood in the bloodstream. This extra fluid in your blood vessels increases the pressure exerted on the vessel wall. This is why we use blood pressure as an important measure of health and disease. (Think of your artery as a water balloon. It can accommodate a certain amount of water. If you put more water in the balloon, the extra water will increase the pressure on the balloon wall, and it will expand to accommodate to keep the pressure even by expanding. The balloon can only accommodate to a certain amount of extra water. Beyond that the pressure on the balloon increases and over time the wall of the balloon breaks down and can even burst).
Over time this pressure stiffens the blood vessels leading to high blood pressure and can eventually cause heart disease. The heart is a pump and like any pump it has to work harder to pump blood through arteries with higher pressure (Have you ever tied inflating a bicycle tire with a hand pump? It is easy at first but takes a lot more effort once the tire pressure is high). The extra pressure causes damage to the blood vessel walls making them stiffer. This further increased blood pressure putting yet more stress on the heart which can cause heart disease, even heart failure. The kidneys also work harder and these too can be damaged.
What health problems are caused or worsened by too much salt?
Eating a high salt diet causes more than just heart and blood pressure problems. The following is a list of diseases or problems that can be caused or worsened by a chronic high salt diet:
- High blood pressure
- Heart disease including heart attacks and heart failure.
- Stroke- High blood pressure damages brain blood vessels
- Chronic kidney disease
- Kidney stones- Excess salt, as a mineral, precipitates in urine to form potentially painful stones.
- Osteoporosis- More calcium is lost to urine as blood sodium increases. Calcium is an important mineral for bone density and strength.
- Cancer- Chronic high salt can potentially increase risk of stomach cancer.
- Obesity- Obesity in turn causes many other health and mood problems
Hidden diseases cause by excessive salt intake.
We seldom think about “the company it keeps” when talking about health problems or benefits gained from any lifestyle change. Often times, one change or one habit is associated with another. This is why the best health benefits will come from a balanced health lifestyle, not a single quick fix. (This understanding of health though a holistic rather than reductionist single focused lens is a philosophy of health based on science and experience. Learn more about my health philosophy in, The company it Keeps). Diet is no exception. Most Americans get too much salt in their diet not because they are overusing the saltshaker but because they are eating poor quality, high salt foods such as processed pre-prepared foods and fast foods. In other words, a high salt diet contains other health robbing qualities such as:
- Too much fat especially hydrogenated oils and saturated fats
- Too much sugar or other highly processed carbohydrates with high glycemic load
- Too little fiber
- Less fruits, vegetables and whole grains meaning little nutrient rich whole foods and disease fighting antioxidants.
- High salt diets change your dietary preference leading to cravings or a preference for saltier foods.