Calcium in vegetable-based diets

Published: 11/10/2005 - Updated: 08/13/2019

Healthy bones, strong teeth: achieving this goal is largely dependent on calcium, one of the most important and abundant minerals in the body, and whose best known source are the dairy products. But an exclusively vegetarian diet can also be rich in this mineral, always consuming the right amounts of products containing it, and proper food combinations.

Many people choose to avoid milk because it contains fat, cholesterol, allergenic proteins, lactose and frequent traces of contamination. Milk is also linked to juvenile diabetes and other serious problems. Fortunately, there are many other good sources of calcium.

Keeping your bones strong depends more on preventing the loss of calcium from the body than increasing calcium intake.

Some cultures do not consume dairy products and typically ingest only 175 to 475 milligrams of calcium per day. However, these people generally have low rates of osteoporosis. Many scientists believe that exercise and other factors have more to do with osteoporosis than calcium intake.

Calcium in the body

Almost all the calcium in the body is in the bones. There is a small amount in the blood that is responsible for important functions such as muscle contraction, maintaining the heartbeat and the transmission of nerve impulses.

Constantly we lose calcium from our bloodstream through urine, sweat and faeces, replenishing with calcium from the bones. In this process, the bones lose calcium continuously. The calcium from the bones must be replaced from food.

The calcium needs change throughout life. Until the age of 30 years or so, we consume more calcium we lose. An adequate calcium intake during childhood and adolescence is particularly important. Subsequently, the body begins to come into a "negative calcium balance”, and the bones begin to lose more calcium they receive. The loss of calcium in excess can cause brittle bones or osteoporosis.

The rapid loss of calcium depends in part on the type and amount of protein intake and other dietary choices and lifestyles.

Reducing calcium loss 

Several factors influence the loss of calcium in the body:

  • Diets high in protein cause more calcium loss in urine. Protein from animal products causes calcium loss more easily than protein from plant sources. This may be one reason that vegetarians tend to have stronger bones than meat eaters.
  • Caffeine increases the rate of calcium loss through urine.
  • Diets high in sodium increase loss of calcium in the urine.
  • Alcohol inhibits calcium absorption.
  • The mineral boron may reduce calcium loss from bones.
  • Exercise slows bone loss and is one of the most important factors in maintaining bone health.

Sources of Calcium 

Exercise and a diet moderate in protein will help to protect your bones. People who carry a vegetarian diet and have an active lifestyle are likely to have lower calcium needs. However, calcium is an essential nutrient for all. It is important to eat calcium-rich foods daily. 

Calcium in foods (in milligrams)

Cereals:

  • Brown rice (1 cup, cooked) 20
  • Cornbread (1 piece of 2-oz.) 133
  • Corn tortillas 42
  • English muffin 92
  • Wheat bread (1 slice) 18
  • wheat flour, all-purpose (1 cup) 22
  • wheat flour (1 cup) 40

Fruits: 

  • Apple (1 medium) 10
  • Banana (1 medium) 7
  • Dried figs (10 figs, 187 grams) 269
  • Orange (1 medium) 56
  • Orange juice, calcium-fortified (8 oz.) 300 *
  • Pear (1 medium) 19
  • Raisins (2 / 3 cup) 53

Vegetable:

  • Broccoli (1 cup, boiled, frozen) 94
  • Brussels sprouts (1 cup, boiled) 56
  • Pumpkin (1 cup , boiled) 84
  • Carrots (2 medium, raw) 38
  • Cauliflower (1 cup, boiled) 34
  • Celery (1 cup, boiled) 64
  • Cabbage (1 cup, boiled) 94
  • Onions (1 cup, boiled) 46
  • Potato (1 medium, baked) 20
  • Romaine lettuce (1 cup) 20
  • Sweet potato (1 cup, boiled) 70

Pulses:

  • Black beans (1 cup, boiled) 103
  • Chickpeas (1 cup, canned) 78
  • Green greens (1 cup, boiled) 58
  • Peas (1 cup, boiled) 44
  • Lentils (1 cup, boiled) 37
  • Beans (1 cup, boiled) 128
  • Soy beans (1 cup, boiled) 175
  • Tofu (1 / 2 cup natural, consistent) 258

Source: J.A.T. Pennington, Bowes and Church's Food Values of Portions Commonly Used. (New York: Harper and Row, 1989.)
* Package information

Examples

Menu Example # 1:

Breakfast: 1 cup of oatmeal with cinnamon and raisins and 1 / 2 cup of soy milk fortified
1 slice toast with 1 tablespoon of almond butter and 1/ 2 grapefruit

Lunch: wheat Pita stuffed with hummus, sliced tomato and lettuce and carrot sticks

Dinner: 1 cup of cooked beans with molasses
Sweet potato and 1 cup roasted or steamed cabbage leaves sprayed with lemon juice and Baked apple

Snack: soy milk shake with banana

Menu Example # 2

Breakfast: 3 oatmeal pancakes topped with apple porridge
orange juice enriched with calcium
fresh fruit

Lunch: corn tortillas with black bean, topped with lettuce and sliced tomato and
spinach salad with tahini-lemon dressing

Dinner:   hinese brown rice: tofu chunks, broccoli, water chestnuts and Chinese cabbage (bok choy)
Pieces of melon drizzled with fresh lemon juice and orange.

Snack: Dried figs

Source: Vegetarian Union Argentina

About the author
  • Dra. Loredana Lunadei

    Dr. Loredana Lunadei is a specialist in food, dietetics and nutrition. She studied at the University of Milan where she obtained a Master in Food Science and Technology. Subsequently, she continued her studies, completing her PhD also at the University of Milan. Linkedin.