Dr. Sarah Penney, ND, MSc
A Salty Diet Can Weaken Your Bones!
We all know that a high intake of sodium can affect blood pressure, but should you still monitor your amounts if your pressures are normal or even low? The simple answer is YES, as there is much more to the story of salt and our health than is apparent! I advise monitoring dietary sodium regardless of blood pressure because high intakes can also increase the risk of encountering osteoporosis – a disease that affects 1 in 3 Canadian women and 1 in 5 Canadian men in their lifetime. This condition can of course lead to serious complications including fractures and decreased mobility, and dietary intervention can be a key part of prevention and treatment.
There are a few different theories about how sodium may affect the health of our bones. What we do know is that in women who have a higher intake of sodium have been shown to lose more calcium in their urine, which means it is being excreted by the body. (1) The first theory as to why this happens involves a delicate balance of our overall acid and base levels. The body has to work very hard to ensure our blood stays in a certain range of slightly basic pH (a level of acidity), which can be particularly hard when we are consuming high amounts of acid producing elements like sodium. What can happen is that our body responds by leeching the calcium from our bones to help neutralize the acid (like using Tums when you have heart burn) to maintain the basic pH of the blood. This may show up in our urine as an increased calcium loss, and lead to a decrease in bone density. This effect may be worse as we age because our kidneys become less able to excrete and manage large acid loads. (2) The other way that sodium may increase urinary calcium loss could be by directly affecting the kidneys in a way that changes absorption of calcium before urine is created, or increases in the filtration of calcium in the kidneys, tricking our body into getting rid of it! (1)
No matter what way it works, increased sodium intake seems to foreshadow decreased bone density. This has been verified in a recent study conducted in Japan looking at sodium intake and bone health of 213 post menopausal women, average 63 years of age. They found that participants with the highest salt intake had more than 4 times the risk of a fracture in any location other than the spine! On average, the women were consuming over 5000mg of sodium per day, with the highest group consuming over 7000mg. This is a huge amount of sodium, and a bit higher than the Canadian average, but surprisingly not too hard to reach depending on your diet. To provide some perspective, the American Heart Association recommends a diet containing less than 2000mg per day for heart health.
Have you ever tried to track how much sodium you have in a day? Challenge yourself to start looking at labels and adding things up, most restaurants even provide nutritional information on their website these days if you are eating out! Surprisingly, the biggest contributor to salt in our diet aside from packaged foods in general is actually bread and bread products! A double whammy if you default to a sandwich with lunch-meat a few times per week.
If you are struggling to make positive changes to your diet or don’t know where to start, consider booking an appointment with an appoitment for nutritional counselling and other naturopathic lifestyle suggestions to help improve your bone density today! Feel free to contact me at either of my clinics or at Sarah.PenneyND@gmail.com if you have any questions about my practice. In the meantime, stay healthy!
- Dr. Sarah Penney, ND, MSc
Heaney RP. Role of dietary sodium in osteoporosis. J Am Col Nutr. 2006; 23(3):271S-27gS
Adverse Effects of Sodium Chloride on Bone in the Aging Human Population Resulting from Habitual Consumption of Typical American Diets. J. Nutr. 2008; 138(2):4195-4225.
Endocrine Society (2013, June 17). Excessive salt consumption appears to be bad for your bones. ScienceDaily. Retrieved November 18, 2013, from http://www.sciencedaily.com /releases/2013/06/130617110931.htm