The Surprising Health Problems from Not Enough Calcium
Learn the surprising ways that calcium supports our health, how much we actually need, and the best food sources (including 20 non-dairy options).
Why care about getting enough calcium from our diets? Calcium is a major structural component of bones and teeth, and also serves as an electrolyte—a type of electricity-conducting mineral needed for regulating nerve impulses, muscle contraction (including the heartbeat), blood pH, and fluid balance. Getting enough calcium is vital for protecting against osteoporosis and bone fractures, especially in conjunction with vitamin D and magnesium. But, it can also help reduce your risk of kidney stones, protect against pregnancy-related high blood pressure, lower your risk of colorectal cancer (and improve survival following diagnosis), help you maintain a healthy body weight, and even reduce PMS symptoms!
Calcium is the most abundant mineral in the human body, composing up to 2% of our total body weight—the vast majority of which is located in our bones and teeth. Along with its famous role in building strong bones, calcium serves as a second messenger in cell-signaling pathways.
Importantly, this nutrient functions as an electrolyte—a class of minerals that dissociate into charged particles (called ions) when dissolved in solution, making them capable of conducting electricity. On the whole, electrolytes help regulate fluid balance within the body, regulate nerve and muscle function (including the heart!), maintain a normal blood pH, and transmit nerve signals!
Calcium was first isolated in 1808 by Sir Humphry Davy (Britain’s leading scientist at the time, and also the inventor of the miner’s safety lamp!), who used electrolysis to isolate calcium from a mixture of lime and mercury oxide. But, humans have been using calcium long before we knew its chemical makeup! The Ancient Romans mixed calcium oxide with water to use as mortar for stone structures, and literature from the 10th century AD references plaster of paris (a mixture of calcium sulphate and dehydrated gypsum) to use for setting broken bones. The word calcium derives from the Latin calx, meaning “lime.”
Along with dairy products (particularly low-fat items), good sources of calcium are bone-in sardines, green vegetables (especially Brassica vegetables like kale, collard greens, turnip greens, bok choy, broccoli, and cabbage), and seaweed. Some other plant foods like spinach, rhubarb, and beans are also relatively rich in calcium, but also contain high levels of oxalate or phytate, which bind to calcium and inhibit its absorption. Other food sources include fortified foods like orange juice, soy milk, and certain cereals.
This article explains the biological roles of calcium, the interactions between dietary calcium and our risk of a dozen health conditions, symptoms and signs that we’re getting too little calcium, problems from too much calcium, how much calcium we need by demographic, and shares the top 25 best common whole food sources of calcium (20 of which are not dairy products!). Paid subscribers also can download a printer-friendly PDF version of this information below!
The Biological Roles of Calcium
Calcium’s two main functions are structural and regulatory: one, supporting skeletal health, and two, helping regulate
