In honor of National Women’s History Month, I came up with my quick and dirty guide to the top 5 nutrients women should pay special attention to.

Here’s #2:

Calcium

Calcium is the mineral you have the most of in your body. You probably know it’s responsible for forming bones and teeth, but did you know it’s also vital for vascular contraction and dilation (and thus plays a role in blood pressure regulation), muscle function, nerve transmission, intracellular signaling, and hormone secretion? The good news is few people have low serum (blood) calcium levels, because the body is good at making sure you have enough free-flowing calcium to keep these functions running smoothly. The bad news is, if there is inadequate dietary calcium intake, the body takes the calcium it needs out of your bones.

Your bones are reworking themselves constantly, throughout your lifetime. During childhood and adolescence, your body is generally laying down more bone tissue than it removes, as periods of growth take place. In your early 20s, your max skeletal mass has been laid down, and the two processes (building of bone and breakdown of bone) happen pretty much equally. In older adulthood (especially for post-menopausal women), however, the breakdown of bone exceeds the rebuilding of bone, and the resulting weakened bone can increase the risk for osteoporosis.

With the exception of pregnancy and lactation, the calcium needs of adults are the same until about age 51 (or earlier, if menopause has occurred). Pregnant, lactating, and post-menopausal women need 1200mg of calcium per day, compared to 1000mg per day for their male counterparts.

Good sources of dietary calcium are milk, yogurt, and cheese. Nondairy sources include vegetables such as Chinese cabbage, kale, and broccoli. Spinach provides calcium, but its bioavailability (the body’s ability to absorb it) isn’t great. Most grains in the US aren’t high in calcium, but because Americans tend to eat them often, they do contribute to our calcium intake. Many fruit juices, tofu, and cereals are fortified with calcium.