We know that calcium is needed for tooth and bone support. What you may not know is that calcium doesn’t work on its own, requires other vitamins and minerals to do its job. Like the three musketeers, calcium needs magnesium and vitamin D to be effectively absorbed. The body doesn’t produce calcium, so the mineral must be sourced form the foods you eat.
How It Works
Calcitonin is a hormone produced by the thyroid gland that regulates blood calcium and potassium levels. Calcitonin also inhibits bone cell breakdown. The more calcium in the body, the more calcitonin is produced (1).
When these nutrients are taken together, each component can do its job for bone health: calcitonin stalls bone cell degeneration while new calcium is absorbed. Magnesium, on the other hand, affects bone mineral density: as calcium moves into the bone cells, magnesium makes sure it stays there.
You could say that without necessary amounts of magnesium, your calcium levels are almost inconsequential.
When Your Bones Get Weak
Osteoporosis is a condition in which bone density is low, making bone and bone tissue weak and susceptible to fracture. Fractures from osteoporosis are more common than the incidence of breast cancer, stroke, and heart attack combined (2).
There are no symptoms of osteoporosis and it’s a cumulative condition so it’s important to ensure you regularly get enough calcium, vitamin D, and magnesium in your diet to keep osteoporosis at bay.
Many people take calcium supplements to keep their bones strong. Supplements do have their place in a healthy lifestyle but the best source of nutrition is always whole foods.
Depending on the kind of supplement you buy, the calcium it contains may not be bioavailable and will collect in your arteries and kidneys instead of in your bones. This can lead to cardiovascular problems and kidney stones—not a happy scenario.
A researcher in New Zealand went so far as to say, “Evidence that calcium supplements prevent fractures is weak and inconsistent.”(3). This goes for fortified foods like milk, too.
Any processed food with added vitamins—D included—is almost always made using synthetic materials.
Other important nutrients for bone health are vitamin K2, which is responsible for transporting calcium through the body, and omega 3 fatty acids, which improve bone strength (4, 5).
The body may not produce calcium, but it does create its own vitamin D— All you need is sunshine. Twenty percent of your skin exposed to sunlight for thirty minutes a day is enough to get your daily dose. The sad fact is that most people don’t spend enough time outside to get that much.
Foods vs. Supplements
Fruits and vegetables often contain the appropriate combinations of nutrients to support each other.
That’s why it’s so important to each a variety of them each day. While not an exhaustive list, below are common foods that contain significant amounts of calcium and vitamin D.
It’s also a good idea to eat leafy vegetables and green grasses, which contain chlorophyll—a pigment that makes them green. The central atom in chlorophyll is magnesium.
Example of bone-healthy foods include:
- Almonds
- Brazil nuts
- Collard greens
- Cottage cheese
- Eggs
- Kale
- Dried wheat grass or barley grass
- Okra
- Parsley
- Sardines
- Salmon
- Sea vegetables: hijiki, wakame
- Seaweeds: kelp, kombu
- Spirulina
- Sunflower seeds
- Turnip greens
- Watercress
- Yogurt and other fermented dairy foods, like kefir
Food sources high in magnesium include:
- Seaweeds, fresh and dried
- Beans
- Beet greens
- Broccoli
- Cucumbers
- Whole grains
- Nuts
- Peas
- Seeds
- Squashes, including pumpkin
- Leafy greens
It’s also important to avoid foods that strip your body of these nutrients, like refined sugars ,which inhibit the absorption of calcium and magnesium.
How much calcium, magnesium, and vitamin D you need on a daily basis depends on your sex and age.(6,7)
When it comes specifically to bone health, weight-bearing exercise strengthens bones and helps to maintain their density. Even moderate exercise like walking makes a difference for bone health.