Calcium in a plant-based diet
Many of us have heard over and over again that milk is an excellent source of calcium. But is it? What are other sources of calcium for individuals who do not drink milk?
Other excellent sources of calcium include green vegetables, legumes, tofu, calcium-fortified fruit juices, almonds, soy milk, and rice milk. Will eating these foods provide our bodies the daily amount of calcium we need, or would we need to take supplements as well?
Why is calcium important for the body?
Calcium is the most abundant mineral in the body. Most of that calcium is found in our bones and teeth. The remainder is found in the blood and extracellular fluids, helping to regulate metabolic functions.
Calcium keeps our bones and teeth healthy and strong throughout our lifetime. Consuming too little calcium can lead to loss of bone density, which increases the risk of breaking or fracturing our bones.
Too much calcium has its consequences, too. Having too much calcium in the body will lead to hypercalcemia, which may cause calcification in soft tissues, particularly in the kidneys—a life-threatening condition. Constipation may also occur when calcium intake is high.
What is the recommend dietary allowance for calcium?
Since calcium is the most abundant mineral in the body, it is important to make sure we are getting enough in our daily diets. For most people over the age of 50, the recommend amount of calcium is 1,200 mg per day. For those under 50 it is recommend to consume 1,000 mg per day.
There is an upper tolerable limit when it comes to calcium. You do not want to exceed greater than 2,500 mg per day.
|Recommended Daily Allowance of Calcium|
|1-8 years||200-260 mg||200-260 mg|
|9-18 years||1,300 mg||1,300 mg|
|19-50 years||1,000 mg||1,000 mg|
|51+ years||1,200 mg||1,200 mg|
|Pregnant or Lactating 19+|
Pregnant or Lactating 14-18 years old
What enhances calcium absorption?
In the average adult, only 30% of dietary calcium is absorbed by the body; it is important we do what we can to increase the opportunities for our bodies to absorb the calcium we ingest. Vitamin D, lactose, protein, sugar, and xylitol are nutrients that aid calcium absorption.
What inhibits calcium absorption?
Some inhibitors of calcium absorption include phosphorus, high levels of salt, zinc, zinc of magnesium, unabsorbed fatty acids, and diets high in fiber. Dietary fiber may cause a decrease in calcium absorption for those consuming greater than 30 grams of fiber per day.
Some other factors affecting calcium are sodium, protein, and caffeine. These inputs increase the amount of calcium lost through urination.
Signs of calcium deficiency
How do you know you are getting enough calcium in your diet? What are some signs and symptoms of calcium deficiency? Hypocalcemia, or calcium deficiency, results in tetany, which is muscle cramping that occurs mostly in the arms and legs. Hypocalcemia can also lead to osteoporosis, the weakening of the bones that causes frequent fractures and breaks. Low calcium levels (less than 500 mg per day) can also lead to high blood pressure.
Calcium plays an important role in our bodies, so it’s important to make sure we are consuming foods rich in calcium. Although the body is able to absorb calcium much easier when it is found in the foods we eat, some people who are deficient in calcium may need to take calcium supplements. Just remember, when we eat foods in their natural form, the body is better able to use their nutritive properties.
|Foods Containing Calcium|
|Food||Serving Size||Calcium (mg)|
|Almonds, whole||1/4 cup||94|
|Almond butter||2 Tbsp||111|
|Blackstrap molasses||2 Tbsp||400|
|Bok choy, cooked||1 cup||158|
|Broccoli, cooked||1 cup||62|
|Collard Greens, cooked||1 cup||357|
|Navy beans, cooked||1 cup||126|
|Orange juice, calcium fortified||8 oz||350|
|Plant milks, calcium fortified||8 oz||200–500|
|Soybeans, cooked||1 cup||175|
|Soy yogurt||6 oz||300|
|Tofu, processed with calcium sulfate||4 oz||200–420|
|Turnip greens, cooked||1 cup||249|
— Kylee Gumm, RD
Mahan, Escott-Stump, Raymond. 13th edition. Food and the Nutrition Care Process. 92–95, 359.
Winston J. Craig, PhD, RD. 2nd edition. Nutrition and Wellness. 196, 197.