Vegan Foods With Calcium / Plant-based Calcium
Calcium-rich foods are of enormous importance for our body. Calcium is an essential mineral for strong bones and healthy teeth. To avoid calcium deficiency, the mineral needs to be consumed through diet. However, with a varied vegan diet, it is very easy to obtain sufficient calcium.
For a table of vegan and calcium-rich foods, click here.
Below are some calcium-containing foods that should be regularly consumed in a mineral-rich diet. These are plant-based or vegan foods high in calcium. However, it should be noted that the absorption of calcium from foods is negatively affected by certain acids found in plant-based foods - see the next two sections.
Oxalic acid inhibits calcium absorption
In addition to the calcium content in the selected foods, the bioavailability also plays an important role. Bioavailability refers to how well a nutrient can ultimately be absorbed by the body from the food. This should be considered when selecting foods. For example, spinach, chicory, chard, rhubarb, as well as amaranth and quinoa contain a relatively high amount of calcium, but it is bound to oxalic acid, which prevents calcium absorption 1. Studies have shown that only a very small proportion, 5.1%, of the calcium in spinach can be absorbed 2. According to the study, out of 200 mg, only 10.2 mg of calcium could be absorbed. The calcium absorption by the body is inversely proportional to the oxalic acid content in the foods 3. Therefore, the more oxalic acid is present, the less calcium is absorbed. The bioavailability of calcium is thus poor.
Below are some examples of how the absorption rates for calcium in plant-based foods vary 4:
|Food||Absorption Rate (%)|
|Sesame seeds, hulled||20.8|
Phytic Acid Reduces Calcium Absorption
Another obstacle to absorption is phytic acid, which, similar to the antinutrient oxalic acid, binds to calcium, making it poorly absorbed by the body 5. Therefore, plants or vegan foods with low levels of phytic acid and oxalic acid should be chosen, as emphasized in this article as well.
By cooking, steaming, or fermenting the respective foods, the negative properties of the acids are significantly reduced 6. However, some calcium is lost when cooking the respective foods 7. Therefore, calcium-rich foods should be cooked for as short a time as possible.
Calcium in Vegetables
The best plant-based sources of calcium with highly absorbable calcium are green vegetables such as kale (150 mg per 100 g), Brussels sprouts (42 mg), cress (120 mg), fennel (49 mg), okra (82 mg), and broccoli (47 mg) 8 9. Kale is particularly noteworthy in this regard. The calcium contained in kale was found to be excellently absorbed during studies because this extremely healthy vegetable contains few oxalates 10.
Other vegetables with higher calcium content include root vegetables such as parsnips (36 mg) and radishes (25 mg). Especially vegetables from the cabbage family have a high calcium bioavailability 11. Recommended calcium sources are pak choi (also known as bok choy, with 105 mg), napa cabbage (77 mg), and cauliflower (22 mg). Dandelion leaves (187 mg) and horseradish are also rich in calcium and should therefore be included on the plate more often.
Dark green vegetables also have the advantage of containing a lot of vitamin K1 and potassium. Both micronutrients are also needed for strong and healthy bones.
For the table with calcium-rich vegetables, click here.
From the group of culinary herbs, dark green herbs such as basil (177 mg), rosemary (317 mg), dried marjoram (2 g), oregano (1.6 g), dill (208 mg), thyme (405 mg), and parsley (138 mg) are extremely rich in calcium.
Seeds and Nuts with Calcium
Nuts and seeds contain phytic acid, which hinders the absorption of calcium. However, there are also good sources with absorbable calcium. These include pecans (70 mg), flaxseeds (255 mg), poppy seeds (1.44 g), as well as chia seeds (0.63 g) and shelled hemp seeds.
It is worth noting brazil nuts (160 mg), which, according to studies, are a very good source of bioavailable calcium 12.
Legumes are also calcium-rich foods. Kidney beans (143 mg), black beans (123 mg), chickpeas (57 mg), and lentils (35 mg) are suitable as calcium-rich foods. Soybeans (277 mg) contain high amounts of oxalic acid and phytic acid, which hinder calcium absorption. 13 14. For this reason, soy milk, plant-based yogurts, and tofu are often fortified with calcium.
Calcium Occurrence in Grains
Grains and grain products contain low levels of calcium. Additionally, grains have higher amounts of phytic acid, which cannot be digested by humans. 15. The best sources are brown rice (33 mg) and wheat (34 mg). White rice only contains 2 mg. However, calcium from white rice was found to be absorbed at 63.6% in vitro, while calcium from brown rice was absorbed at 27.6% 16. Since rice is often consumed in larger quantities in a varied vegan diet, it also contributes to meeting the daily calcium requirements.
The South American pseudo-cereal canihua is low in phytic acid and contains a significant amount of calcium, at 110 mg.
Fruits as calcium-rich foods
Available calcium is also found in fruit - albeit in smaller quantities. The best representatives in this group are figs (35 mg), lemons (26 mg), strawberries (16 mg), pineapples (13 mg), apricots (13 mg), cherries (13 mg), mangoes (11 mg), grapes (10 mg), plums (6 mg), apples (6 mg), and bananas (5 mg).
Berry fruits like dried goji berries (190 mg), black currants (55 mg), blackberries (29 mg), and raspberries (25 mg) contain calcium in smaller amounts.
To access the table with calcium-rich fruit, click here.
Calcium in Processed Products
Processed products now also contain calcium or the particularly calcium-rich algae Lithothamnium. Another supplement in vegan foods is often vitamin D, which is necessary for the absorption of calcium from food.
Calcium supplements can also be found in plant-based drinks and fruit juices. They are also suitable for meeting the daily calcium requirement. Tofu and breakfast cereals, depending on their preparation, can also contain high amounts and can be considered as calcium-rich foods. Checking the ingredients and nutritional information provides more details. Tofu enriched with calcium is proven to be a good source of bioavailable calcium according to studies 17.
Two other good sources of calcium are mineral water (33 mg) and oatmeal (351 mg).