Sunday, February 11, 2018

Bad to the Bone! Are you at risk for Calcium and Vitamin D Deficiency?

"I wish I knew now what I didn't know then."  These words have never rang more true to me.  A couple of months ago, I was in the midst of training for my fourth marathon (and before I go on, for my non running friends, all marathons are 26.2 miles, but no two marathons are alike.  The course vary, as does the weather, the runners energy level, and so on).  Typically, a runner trains for about 4 months in order to prepare for a full marathon.  I was about half way through this process.  I had been running aggressively with some extremely fast and decorated runners (you know who you are), and my goal was to get my marathon time down on order to possibly, maybe qualify for the Boston Marathon, which is the pinnacle for most runners.  I was on course for my goal, running hills, pace runs, pick ups, and long runs. I was up to the 18 mile point and had a successful long run despite the late heat and humidity in the fall, and the fact that I was getting less sleep than needed because my son was  playing his final senior season of football.  During that 18 mile run, I noticed that I had a pain in the back of my leg almost behind my Achilles tendon, maybe a bit higher.  I went home and started the RICE method (Rest, Ice, Compression, and Elevation), thinking that it must be Achilles tendonitis, which isn't uncommon in marathon runners.  I rested all of Saturday and Sunday (meaning that I didn't work out except for yoga) and returned to my training on Monday with a 7 mile run.  By Wednesday, my leg was highly aggravated and it hurt to walk.  So I took Thursday and Friday off and attempted to run my Saturday long run.  I made it a mile before I was in excruciating pain.  I had to turn around and hobble back to my car.  Disappointed and dismayed, I knew it was time to see the doctor.

Long story short, I found out that I had developed a stress fracture in my tibia, one of the larger bones in the lower leg.  This would be my second stress fracture in two years (the first was in my femur, the long bone in the thigh area) which I was diagnosed with after my second marathon.  What is significant about these fractures is that they were both in substantial bones that are atypical of stress fractures; smaller bones are much more susceptible to small stress fractures.  Besides learning that my goal of completing the marathon I had been training for was over, I also learned that I had a condition called osteopenia.  Osteopenia is diagnosed with a bone density test and is absolutely the least invasive medical test that I have ever experienced.  Osteopenia occurs when calcium has leached out of the bone or possibly there was never an adequate supply ther in the first place.  Calcium is best absorbed during childhood and adolescence when the bone is still growing and calcium absorption is at it's highest.

Unfortunately, I was not a registered dietitian (Or even a healthy eater) during my adolescence years and I replaced milk at school lunch early on with sodas possibly contributing to my osteopenia.  Sodas (it doesn't matter which ones) have an additive called phosphoric acid, which helps to maintain the "fizz" of the soda.  Phosphorus is an important mineral in the diet and needed for multitudes of biochemical pathways in the body, however, because of food additives found in sodas and even packaged bakery products, it is easy to consume more phosphorus than calcium consumed (Other food sources of phosphorus include edamame, mushrooms, potatoes, rice, cereals, milk, meats, beans, and eggs).  Ideally, calcium and phosphorus would be consumed at a 1:1 ratio.  It is estimated that the average American consumes a calcium to phosphorus more like 1:3 because of the vast variety of foods naturally containing phosphorus and the addition of phosphoric acid in processed foods to maintain extended freshness.  This unbalanced ratio creates an undesirable absorption scenario where less calcium is absorbed.  In addition, calcium is found in a lesser variety of foods, such as milk, yogurt, cottage cheese, salmon, and almonds.  As a teen, I did not drink milk, eat yogurt, cottage cheese, and rarely ate salmon, nor did I supplement calcium.

Bone growth is extremely interesting.  During adolescence, calcium is absorbed in the bone like a water into a dry sponge, but sometime in late teens to early 20s, that sponge becomes resistant to absorbing calcium and continues to decrease.  Complicating matters even more for females is pregnancy and lactation.  Calcium intake during pregnancy is vital for both mom and baby.  If mom is not consuming adequate dietary calcium, the calcium will be leached from mom's bones and teeth.  Prenatal vitamins generally contain 100% RDI for iron and minimal calcium.  This is because iron deficiency is the most prevalent acute deficiency during gestation.  Calcium is not added at the full RDI because it will inhibit the iron absorption.  The best alternative is to take the prenatal vitamin (or if you are not pregnant and take a multivitamin/multi-mineral supplement) at one end of the day and a calcium supplement at the opposite.  For example, I eat dairy products more often at breakfast, so I would take the calcium supplement in the morning and the iron containing supplement at bedtime to reduce and chance of interaction.

Vitamin D is also an important part of the equation to bone health.  Vitamin D controls calcium content in the blood, bones, and urine.  As an East Texan, I like to relate Calcium and Vitamin D to a pasture full of cattle.  Let's pretend that you were given 100 acres of land with 100 cows included , but no fence.  Would you expect the cows to remain on your 100 hundred acres?  Of course not.  The fence is needed to keep the cows in and to also deter others from freely stealing the cows off of the land.  In this made up scenario, the cows are representative of the calcium that should be stored in the bone and fence represents Vitamin D.  In this example, it would not matter how many cows were continually replaced, it would be an endless loss.  This is what happens when adequate calcium is either consumed from food or supplement, without adequate Vitamin D.

Vitamin D is even more elusive in foods than calcium.  Nutrition experts once thought Vitamin D deficiency was rare, however, current research has reveled that more than 3 million cases of Vitamin D deficiency is diagnosed each year, dramatically increasing in adolescence throughout the lifespan.  Although Vitamin D can be produced in the skin with exposure to sunlight, desk jobs, computerization, sunscreen, and limited exposure to outdoors have contributed to low Vitamin D levels. It is only found in fortified foods and beverages (fortified means it is added to a product and that it is not naturally found there).   The most common foods that are fortified with Vitamin D are generally dairy foods, which is both good and bad news.  The good news is that calcium and Vitamin D are found in the same foods.  The bad news is that calcium and Vitamin D are found in the same foods; therefore, if milk or dairy products are not consumed or tolerated, then potential deficiencies of calcium and vitamin D are likely to coexist, unless supplemented.  Vitamin D and calcium can be supplemented easily with traditional dietary supplements or newer versions, such as Viactiv calcium chews fortified with Vitamin D.  The Viactiv chews are often preferred to traditional supplements, as the chocolate or caramel chew is more palatable and delivers the same dose contained in the more traditional supplements.

Since being diagnosed with osteopenia, I have become more aware of my calcium and Vitamin D intake.  I currently eat a wide variety of foods, including yogurt, cottage cheese, and almonds.  In addition, I do supplement with calcium and Vitamin D, as recommended by my doctor after having serum levels checked.  Also, I am limiting my intake of foods and beverages containing phosphoric acid, including processed foods and sodas.  In addition, it is important to partake in strength training (weight lifting and/or using one's own body weight) to strengthen the bones and supporting muscles. 

I have had lots of well meaning non-running friends advise me to quit running, pointing out that running caused my stress fracture.  The fact is, however, challenging my running intensity and duration was not the only cause the stress fracture.  My stress fracture was actually predicated by my poor diet during those vulnerable years and would have eventually happened with or without the running.  I actually think by having the stress fracture, and then being diagnosed with osteopenia early may be a blessing as I became aware of a problem and now I can earnestly work to improve my bone health before it become osteoporotic.  I am currently back on the road, running slower, but more appreciative of every mile.  I can't wait for my next marathon!

Full disclosure:  Leslie Goudarzi is not affiliated with any product mentioned and does not receive any monetary benefit from such products.

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