Gabriella Rao, RD

This week’s micronutrient is calcium! Calcium is especially important for runners to promote bone density and reduce risk of stress fractures, as well as to support muscle function.

Functions of calcium:

• bone and tooth health
• muscle contraction and relaxation
• nervous system function
• dilation and contraction of blood vessels

Symptoms of deficiency:

• difficulty swallowing
• muscle cramping
• lethargy
• numbness
• weak or brittle nails
• stress fracture

Food sources of calcium:

• Cow’s milk or fortified alternative milk — 300 mg per 1 cup
• Yogurt — 330 mg per 3/4 cup
• Salmon or sardines w/ bones — 240 mg per 1/2 can
• Cheese — 250 mg per 3cm cube
• Tempeh — 110 mg per 4 oz
• Kale — 105 mg per 1 cup
• Beans — 95 mg per 1/2 cup
• Almonds — 95 mg per 1/4 cup
• Sesame seeds — 95 mg per 1 tbsp
• Spinach — 145 mg per 1/2 cup
• Gelato!!

The RDA for calcium is 1000-1200 mg for most adults. Vitamin D plays a role in intestinal calcium absorption, helping to increase the percentage of calcium absorbed.

What to do if you think you may be calcium deficient:

• Get some labs!
  • Total calcium: measures both bound and free calcium in the blood. The most typical lab to measure calcium status.
  • Ionized calcium: measures the free calcium in your blood. This lab is usually used if your total calcium labs are abnormal.
• Add more calcium-rich foods into your diet 
  • Dairy or fortified dairy alternatives, seeds, nuts, beans, cooked dark leafy greens, tofu, salmon, sardines, etc.
• If unable to improve calcium status through diet modification, work with your RD or doctor to obtain an appropriate supplement — never supplement blindly!
  • Always make sure any supplement you take is third-party approved (meaning that it has been tested in a lab to ensure that it contains the correct ingredients in the amounts advertised on the label)