Vitamins and Minerals 4 MIN READ 101 VIEWS July 27, 2021

Understanding Calcium Supplements – Their Role and Bioavailability

dietary calcium

Calcium is one of the most essential nutrients required to support the optimal functioning of your body. It carries out important tasks such as circulating the flow of blood and oxygen and blood in your body, controlling the movement of the muscles and regulating the secretion. Additionally, calcium supplements are also responsible for ensuring the proper transmission of neural messages from the brain to the rest of your body.

One of the things that makes calcium supplements so important for your body is the fact that it is found in about 99% of our body, due to its presence in both our bones and teeth. Not getting the required amount of calcium could in fact lead to severe health complications. 

Sources Of Dietary Calcium

dietary calcium

Since your body is incapable of producing and synthesising calcium on its own, you will need to consume dietary calcium from external sources such as natural whole foods in order to meet the recommended calcium needs.

Given below is a small list of foods that are rich in calcium:

  • Dairy Products: milk, cheese, and yogurt
  • Dark Green Vegetables: kale, spinach, and broccoli
  • Fortified Foods: calcium-fortified breads, cereals, soy products, and orange juice

Bioavailability Of Calcium Supplements

The bioavailability of a nutrient refers to how easily and quickly it can be absorbed and digested by our body. Since calcium is a relatively large nutrient, it takes a bit longer to be broken down by the gut. This means that while you may be consuming a lot of calcium supplements on paper, your body is actually getting lesser amounts of calcium than you think you are.

calcium content

Fortunately, there are certain foods whose calcium content is more easily absorbable by the body than other sources. 

FoodServing sizeAverage calcium content (mg)8Estimated absorption (%)9-11Calcium absorbed (mg)Servings required to equal 250 mL (1 cup) of milk
Milk calcium
Milk calcium (whole, 2%, 1%, skim)250 mL (1 cup)31032.199.51
Cheddar cheese50g (1.5 oz)33732.1108.21
Yogurt175 mL (3/4 cup)27232.187.31
Vegetables (cooked)
Bok choy125 mL (1/2 cup)8453.845.22.25
Kale125 mL (1/2 cup)4949.324.24
Broccoli125 mL (1/2 cup)3361.320.25
Spinach125 mL (1/2 cup)1295.16.615.25
Nuts & seeds
Almonds60 mL (1/4 cup)9721.220.64.75
Sesame seeds60 mL (1/4 cup)2320.84.820.75
Legumes (cooked)
White beans125 mL (1/2 cup)8521.818.55.5
Pinto beans125 mL (1/2 cup)4226.711.29
Red kidney beans125 mL (1/2 cup)2624.46.315.75
Breads & Cereals
Whole wheat bread35 g (1 slice)268221.34.75
Wheat bran 27 g19387.213.75
Fortified foods
Orange juice with calcium 125 mL (1/2 cup)15536.356.31.75
Tofu, regular, firm or extra firm, raw (prepared with calcium sulphate)85 g171*31532
Soy beverage with tricalcium phosphate250 mL (1 cup)3192476.61.25**

One of the major disadvantages to consuming plant based sources of dietary calcium is that these foods sometimes contain compounds called anti nutrients. Nutrients such as oxalates and phytates attach themselves to the calcium that you consume and make it harder for your body to absorb them.

For example, a single bowl of spinach would give you about 250 milligrams of dietary calcium but it also contains a lot of oxalates which means that only 14 grams of calcium is actually being absorbed and utilised by your body. This is the case with other forms of calcium such as milk calcium as well.

This is not to say that you should stop consuming these foods altogether, The primary goal here is to optimize your consumption of calcium products in such a way that your daily calcium needs are met. One of the safest ways to do this is to consume a healthy balanced diet in combination with calcium supplements. 

Recommended Daily Allowance Of Calcium Supplements

The Indian Medical Association recommends that the average adult consume 1000 mg of calcium supplements a day in order to support optimal functioning of the body. However, the calcium needs also vary according to the age and physical condition of the concerned individual.  Always consult with a physician before supplementing your diet with any calcium products. 

What Happens If You Don’t Consume Enough Dietary calcium

Not maintaining the right intake of dietary calcium for a long period of time, a calcium deficiency can manifest in your body, affecting its ability to absorb nutrients of any kind. Given below are a few symptoms for the same:

  • Muscle cramps or weakness
  • Numbness or tingling in fingers
  • Abnormal heart rate
  • Poor appetite

Benefits Of  Consuming Calcium Supplements

Given below are some of the benefits of including calcium supplements in your daily nutritional intake:

  • Bone health: Calcium is required for maintaining the structural density and promoting the growth of bones in our body. It also helps in forming a protective layer of enamel around our teeth to prevent it from being affected by decay.
  • Muscle contraction: Our body is signalled to release calcium upon being stimulated by a nerve. This is required to aid the protein molecules in our body to stimulate contraction and expansion of muscles. 

Additionally, calcium supplements also help with reducing the bad cholesterol levels in our body and reducing the oxidative stress exerted on the heart. This helps in preventing health complications such as heart disease and obesity.

Head on over to for calcium products and other health products that can help you stay fit and healthy.

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