Dr. Chris Magryta: Micronutrient No. 3 — Calcium
Published 12:00 am Sunday, January 31, 2016
Calcium: Third on my list of important minerals.
It is a mineral involved in many reactions in the body. It is found primarily in our bones and teeth, which are used as storage sites. The body carefully regulates calcium levels by stealing from the bones when the system needs more.
Calcium is critical for the function of blood vessels, muscles, neurologic and intracellular signal transmission. It is also critical for hormone secretion. This covers every aspect of feeling good and moving with fluidity.
Based on age, we need roughly 1000mg daily. This should be derived primarily by diet.
Current evidence suggests that supplementing above 500mg for a 70 kg human is not a good idea. Calcium supplements require acid to absorb and therefore should be taken with food. Supplemental absorption decreases with age and is poor in adulthood, at 15-20%.
Phytic and oxalic acid decrease absorption. Foods loaded with phytic acid like unsoaked beans will reduce the absorption of calcium in food or supplements.
Food sources of calcium are primarily dairy, fish with bones (salmon/sardines/smelt/anchovies), organic soy/tofu and leafy greens.
Vitamin D is necessary for gut absorption of calcium. Diets high in sodium and caffeine will decrease calcium absorption.
Deficiency states occur with disease. Kidney disease, vitamin D deficiency, GI absorption disease and certain medications (diuretics/antacids/steroids) all can lead to a deficiency state.
Symptoms of deficiency include muscle twitching and cramps, numbness in your extremities and eventually abnormal heart beats, seizures and death.
My real concern about calcium is rooted in insufficiency states. The long term consequences are bad. Osteoporosis or bone weakness is the major side effect of chronic insufficiency which in turn leads to excessive fractures.
I do not recommend supplements unless advised by a provider. Work hard to get adequate calcium through your diet (roughly 1000mg daily for adults) and make sure that you are getting adequate sun exposure daily.
Daily exercise is also critical for laying down new bone (osteogenesis).
If you do need a supplement, take calcium citrate 250mg twice daily for an adult and less for children, based on provider recommendations.
Most of your bone is laid down before the third decade of life is completed. This is important for parents to pay attention to, as inadequate calcium intake can set a child up for osteoporosis as an adult.
Take home point: Make sure that your kids are active, eating a balanced calcium rich diet and getting 20 minutes of daily sun exposure.
Magryta is a physician at Salisbury Pediatric Associates. Contact him at newsletter@salisburypediatrics.com