Importance of Calcium

Calcium is a mineral in the body that is known for building and maintaining strong bones. But did you know calcium is also important for blood clotting and blood pressure regulation?

We spoke to HOI’s Registered Dietitian Nutritionist, Reema Kanda, to learn about which foods are high in calcium, its role in the body and when to take a calcium supplement.

Q: Which foods are high in calcium and Vitamin D?

A: Dairy foods such as milk, cheese, and yogurt have high amounts of calcium as they will have greater than 300 milligrams of calcium per serving. Fortified nondairy alternatives are also good sources of calcium. Also, ½ cup of broccoli, kale, and mustard greens are good sources of calcium if one does not fancy dairy foods or dairy alternatives. It’s important to highlight that increased portions are needed to be consumed from these vegetables to consume a similar amount of calcium that is in a 1-cup of milk.

Foods that are naturally rich in Vitamin D are milk, fortified juices, margarine, soy milk, cod liver oil, egg yolks, and fatty fish such as tuna, salmon, and mackerel. It’s important to note that an individual’s Vitamin D status depends mostly on sunlight exposure and secondarily on dietary intake of Vitamin D.

Q: What does calcium do in the body? Why is it important beyond bones?

A: 99% of the body’s calcium is stored in the bones and teeth. The remaining 1% has important physiologic functions. It is a mineral that is important beyond just bone health. Its function in the body is that it regulates nerve transmission, muscle contraction, bone metabolism, blood pressure regulation, and is necessary for blood clotting.

Q: What’s the role of vitamin D in boosting calcium absorption? Is there anything else people can do to boost calcium absorption?

A: Vitamin D plays a pivotal role in calcium uptake and therefore bone homeostasis or balance. The main function of Vitamin D is to maintain serum calcium and phosphorous levels within a constant range. Vitamin D is important in stimulating the intestinal calcium transport and stimulates activity of osteoclasts in bone. What this means is Vitamin D is important for increasing calcium availability.

Other nutrients such as Vitamin K is important for blood clotting, however it’s also necessary for bone formation and mineralization. It supports Calcium and Vitamin D to do its job in the body.

Q: When are calcium supplements a good idea?

A: Recommended intakes for calcium range from 1,000 milligrams to 1,300 milligrams per day, depending on age and gender. An upper limit of calcium intake has been estimated to be approximately 2,000-2,500 milligrams per day. Calcium supplements from reputable manufacturers can be of benefit only when the diet is deficient of calcium.

It is also possible to take in too much of a good thing. You do not want to take calcium in excess from diet and supplements combined to avoid toxic effects such as constipation, kidney stones, kidney failure, heart function problems, and confusion and cognitive problems. If your diet is deficient, your body will borrow it from your bones, eventually weakening them.

Q: What are your top three high-calcium foods? Why is each great?

A: My top three high-calcium foods are:

1. Low fat Greek Yogurt because you get a high-quality protein that also support bone health along with calcium and Vitamin D.

2. Kale because you get a load of other vitamins and minerals that supports good health. It contains Vitamin C which is important for collagen synthesis and collagen is the main protein in the bone.

3. Edamame or called soybeans is an unprocessed soy-based food that also contains good amounts of calcium that can be added to salads or enjoyed as a snack.