Walnuts have a moderate calcium content. They can help us meet our daily needs, as a serving provides 3% of the required daily intake. Other nuts, such as almonds, are much richer in calcium, though.
How much calcium is in walnuts?
Walnuts contain moderate amounts of calcium. They contain between 61 and 98 mg of calcium per 100g, depending on the variety.
English walnuts have the highest calcium content than other walnut varieties. This common walnut variety contains 98 mg of calcium per 100g. A cup has 78.4 mg of calcium, while 1/4 cup has 19.6 mg of calcium. A handful of walnuts (about 7 walnuts) has 27.8 mg of calcium, or almost 3% of the Daily Value (DV).
On the other hand, black walnuts have the lowest calcium content. They have 38% less calcium! Black walnuts have only 61 mg of calcium per 100g. A serving provides 17.3 mg of calcium, or less than 2% of the DV.[1]
But, black walnuts have a better nutritional value than English walnuts. For instance, they have a much higher potassium and magnesium content.
Are other walnut-based foods high in calcium?
Furthermore, more walnut-based foods contain moderate amounts of calcium. Refined flours and eggs have a low to moderate calcium content. Only fortified foods and foods containing cow’s milk are great dietary sources of calcium.
| calcium (mg) per 100g | calcium (mg) per serving | % DV | |
| cookies | 33 | 37 | 3.7% |
| granola | 87 | 26 | 2.6% |
| butter | 67 | 20 | 2% |
| flour | 100 | 15 | 1.5% |
| soft cake | 56 | 10 | 1% |
| bread | 12 | 7 | 0.7% |
| brownie | 0 | 0 | 0% |
| oil | 0 | 0 | 0% |
You can buy walnut flour, butter, as well as a wide variety of other nut products on Amazon.
Do walnuts have more calcium than other nuts?
In addition, walnuts have a moderate calcium content as compared to other common nuts. Only almonds. Brazil nuts, hazelnuts, and pistachios are richer in calcium than walnuts.
Almonds are the richest nuts in calcium. A serving provides 7.6% of the DV! Actually, almonds have almost 3 times more calcium than walnuts. Almond milk is also particularly rich in calcium!
| calcium (mg) per 100g | calcium (mg) per serving | % DV | |
| almonds | 269 | 76 | 7.6% |
| Brazil nuts | 160 | 45 | 4.5% |
| hazelnuts | 123 | 35 | 3.5% |
| pistachios | 105 | 30 | 3% |
| walnuts | 98 | 28 | 2.8% |
| peanuts | 89 | 25 | 2.5% |
| pecans | 70 | 20 | 2% |
| macadamia nuts | 70 | 20 | 2% |
| chestnuts | 67 | 19 | 2% |
| cashews | 45 | 13 | 1.3% |
| pine nuts | 16 | 5 | 0.5% |
But, the richest vegan food in calcium per serving is tahini. Tahini is made of sesame seeds.
Do we absorb calcium of walnuts?
Actually, cow’s milk, dairy products, and fortified foods are the most bioavailable sources of calcium. We absorb about 30% of calcium of dairy and fortified food.
Most plant-based foods have lower absorption rates than cow’s milk and dairy, though. They contain certain compounds, which inhibit calcium absorption. For instance, walnuts, as well as other nuts, are high in phytic acid, which prevents calcium from being absorbed.
Phytic acid binds to minerals and makes them unavailable due to its chelating property. Phytic acid inhibits absorption of calcium as well as other minerals, like iron, zinc magnesium and manganese.[2]
Walnuts are particularly high in phytic acid. They have a phytic acid content between 0.2 and 6.7 g per 100g of dry weight. In fact, walnuts are considered phytic acid rich foods.
What foods inhibit calcium absorption?
Besides phytic acid, you should avoid consuming foods rich in calcium or taking calcium supplements, with foods high in oxalates.
Foods high in oxalates have the worst absorption rate of calcium. For instance, we only absorb 5% of calcium from spinach, collard greens, sweet potatoes, rhubarb, and beans, which are particularly rich in oxalates. Also, dark chocolate may impair calcium absorption, due to its high oxalate content. Moreover, chocolate is low in calcium.
The high levels of oxalic acid in these foods form indigestible salts with calcium, decreasing its absorption.[3]
Plant-based foods, which don’t contain oxalic acid, are broccoli, kale, and cabbage. Actually, these foods have a similar calcium absorption rate to cow’s milk.
High amount of caffeine and phosphorus can decrease calcium absorption as well. So, avoid consuming tea, coffee, energy drinks, or other caffeinated beverages with foods high in calcium.
How to increase the absorption of calcium?
Above all, we must have normal levels of vitamin D for proper absorption of calcium. However, there aren’t many common foods high in vitamin D. Hence, vitamin D deficiency is pretty common. In fact, many people would benefit from taking vitamin D supplements. You’ll find a wide variety on iHerb.
Moreover, soaking and rinsing seeds and nuts improves the bioavailability of calcium and other minerals. The germination of seeds and nuts improves the absorption rates of calcium. In addition, soaking and rinsing decreases their oxalate content.
How much calcium do we need a day?
The recommended daily intake of calcium is 1,000 mg for adult women and men. Only women older than 50 years should get at least 1,200 mg of calcium a day, due to increased risk of osteoporosis. Calcium absorption declines with age.
Moreover, children older than 13 years and teenagers require at least 1,300 mg of calcium a day, due to rapid bone growth.
Can walnuts help us meet our daily needs?
Although walnuts aren’t particularly rich in calcium, they can help us meet our daily needs. 14 walnuts (or 2 handfuls) a day can provide up to 6% of the DV.
We shouldn’t eat more walnuts in order to get calcium, though. Overconsumption of walnuts can make you gain weight. Walnuts have many calories.
When should I eat walnuts?
The best time to eat walnuts for weight loss is between meals, as a healthy snack. You can eat walnuts on an empty stomach. Walnuts are low in carbs and sugar. They don’t spike blood sugar levels. In fact, walnuts can control glycemic response of a meal! In addition, fiber and protein in walnuts promote satiety.
Another great time to eat walnuts is before bed. Walnuts support a good night’s sleep!
Can you get too much calcium from walnuts?
Healthy people can safely consume walnuts. We won’t exceed the maximum safe dose of calcium by eating walnuts.
In fact, calcium toxicity is rare in healthy people. High levels of calcium in the body are usually the result of cancer or other health conditions.
However, we shouldn’t get too much calcium. High amounts of calcium can cause constipation, nausea, weight loss, fatigue, renal insufficiency, and heart arrhythmias. Moreover, extremely high chronic calcium intake may increase the risk of kidney stones, cardiovascular disease and prostate cancer.
Common foods high in calcium
Cow’s milk and cheese are the main dietary sources of calcium for people who follow the standard Western diet. Fish and eggs are other animal-derived foods with decent amounts of calcium.
We can get high amounts of calcium from plant-based sources as well. Beans, seeds, nuts, whole grains, dried fruits (e.g. raisins), and certain vegetables, such as kale, spinach, cabbage, and broccoli, can help us meet our daily needs.
In any case, healthy people who follow a well-balanced diet are rather unlikely to be deficient in calcium.
Health benefits of calcium
Calcium is the most abundant mineral in the body! It’s necessary for strong bones and teeth. Furthermore, calcium is involved in muscle movement and flexibility, blood vessel contraction and dilation, blood clotting, nerve transmission, and hormonal secretion.
In addition, getting enough calcium may lower the risk of developing cardiovascular disease, hypertension, stroke, atherosclerosis, osteoporosis, and certain cancers.[4]
