Many of us think of essential nutrients in relatively simple terms: protein is for your muscles, iron is for your blood, and calcium is for your bones. Though the full story is obviously more complex, it’s not a bad summary in the case of calcium. 99% of the calcium in your body is stored in and used by your teeth and bones, and this is the calcium that’s affected by your diet. The other 1%, called serum calcium, is stored in your blood and isn’t affected by diet. (1) So for our purposes, we won’t concern ourselves with the 1% (insert your favorite wealthy-person joke here).

The other 99% of our bodily calcium takes on the crucial job of keeping our bones and teeth firm and strong. Throughout our lives, our bones actually remodel themselves frequently, taking up calcium and using it to form new bone-bits. (1) That’s why we can’t just stop worrying about our calcium when we “stop” growing—our bones actually don’t stop changing. They need constant sources of dietary calcium to perform that vital work. When we don’t get enough calcium, we’re at risk for osteopenia—a thinning of bone density. (2) Left unaddressed, osteopenia can lead to full-blown osteoporosis (“porous bone”). Folks with osteoporosis have significantly less bone density than they should, and they’re at an increased risk of bone fractures. (3)

As most of us know, postmenopausal women are one of the most at-risk groups for this disease. That’s because decreases in estrogen production during menopause reduce calcium absorption and increase bone resorption (the actual process by which your body breaks down calcium stored in bone and releases it into the blood). (1) But just being female puts you at an increased risk for osteoporosis, as does being caucasian, having a small body size, and being physically inactive. It’s important for children—especially girls—to reach their peak bone mass before adulthood, because having a high bone mass as a young adult is a solid indicator that you’ll retain that bone mass throughout your life. (3)

So, now to the million-dollar question(s): What should one eat to obtain maximum calcium? And how much calcium do we need, exactly? The NIH’s recommendations are a great place to start. As a non-pregnant, non-lactating female between 19 and 50, I need 1,000 mg a day. Where can I find those milligrams? Well, I can get 400 mg in just two tablespoons of my BFF blackstrap molasses. A cup of collard greens has 357 mg. Four ounces of tofu processed with calcium sulfate can offer anywhere between 200 and 400 mg. Various beans, greens, and calcium-fortified non-dairy products are also great places to start. There are a few factors that affect calcium absorption, however:

• Vitamin D (whether food- or sun-derived) improves calcium absorption. (1)
• Phytic acid and oxalic acid, which occur naturally in some plants (e.g. spinach) can inhibit calcium absorption. (1)
• A high-protein diet can increase calcium excretion, but recent research indicates that simultaneous processes actually improve absorption, so the effects could cancel one another out. (1)

Whew! That’s a lot to think about. Let’s get to some food now.

Pumpkin Overnight Oats
Serves one

1/2 C + 1 T nondairy milk
1/3 C pumpkin puree
1 T blackstrap molasses (you can add more if you’re a fan like I am)
1 T pure maple syrup
1/2 tsp cinnamon (I actually prefer closer to 1 tsp, but again, that’s just me!)
Dash nutmeg
1/2 C rolled oats

In a mason jar or other container with a tight lid, combine all ingredients except the oats. Shake vigorously until well-combined. Add the oats and shake again. Place in fridge and cool overnight.

Diehard readers might recognize this recipe from last year’s MoFo. I have to share it again, though, because it’s a great source of calcium! One jar gives you at least 30% of your daily value (more if you load up on the blackstrap molasses). That’s a great way to start your day.

Sources cited:

(1) http://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/
(2) http://www.spineuniverse.com/conditions/osteoporosis/osteopenia-osteoporosis-there-difference
(3) http://www.cdc.gov/nutrition/everyone/basics/vitamins/calcium.html

Note:

I’m neither a doctor nor a dietitian; please don’t treat my posts as medical advice! Consult a medical practitioner for specific medical or nutritional recommendations.