Your Guide to Getting Enough Calcium on a Vegan or Plant-Based Diet
You probably didn’t grow up hearing “drink your kale smoothie for strong bones!” or “eat your tofu to have fewer cavities!” If you’re increasingly eating more plant-based foods, you may wonder whether it's possible to get enough calcium to stay healthy.
Experts believe that plant-based or vegan diets can supply plenty of calcium, along with other important nutrients your body needs that you may believe can only be attained if you eat meat and dairy. Calcium is one of the most debated areas of nutrition, and it’s worth getting some background on why it matters, and what to eat to get your daily recommended value.
Why is calcium important?
Calcium is the most abundant mineral in the human body – and it’s key for good health, including bone health. In fact, 99 percent of the calcium in your body is stored in the bones and teeth. But it’s also a critical mineral to help your body get and maintain overall healthy cell functioning: Calcium enables blood to clot, serves a pivotal role in muscle contraction, supports regular heart rhythm, keeps nerves working as they should, and helps the cells regulate metabolism.
Calcium has a role in preventing or treating numerous conditions that are connected to cell growth and metabolism. One common finding: Calcium prevents bone fractures and osteoporosis and plays a role in maintaining healthy blood pressure and treating and preventing hypertension.
Calcium contributes to weight loss and your body's ability to maintain a healthy weight. Low calcium levels have been linked to worse symptoms of premenstrual syndrome, and an increased risk of colon cancer, according to the Journal of Obstetrics and Gynecology. It’s also associated with being deficient in other nutrients such as vitamin D since they work together to help the body absorb this vital nutrient. According to a metanalysis published in the journal Immunity, Inflammation, and Disease, low levels of calcium are predictive of worse symptoms of COVID-19.
How Much Calcium Do You Need?
The recommended daily amounts of calcium are 1,000 mg a day for adult women and men up to age 50 and after that, the recommended levels go up to 1,200 milligrams a day. Many people don’t meet those recommendations, according to numerous sources, including Osteoporosis International, even though the RDA for calcium is 1,300, set by the USDA.
Calcium for bone health
Our bodies form and reform bones daily, throughout our whole lives. Bone formation early in our lives is critical since by your mid-20s peak bone mass is achieved for the spine and hip. But other bones are still growing and maintaining strong bones requires attention.
After adulthood, bone mass declines in both men and women, and bone loss is of special concern for post-menopausal women. Getting enough calcium is critical for this process but so is healthy eating overall and other lifestyle behaviors such as exercise, according to the authors of a review in Therapeutic Advances in Musculoskeletal Diseases. High-impact exercise is a critical means of keeping bones healthy and strong.
Top Vegan Sources of Calcium from Food
If you are eating plant-based you may not be getting enough calcium in your daily meals. To prevent any calcium deficiencies, focus on eating a calcium-rich diet. “Calcium is a bit trickier to learn about and I’d recommend for vegans to become familiar with higher calcium foods,” says Nicole Stevens, MSc, RD, and owner of Lettuce Veg Out.
The 5 food categories high in calcium
1. Fortified plant-based milk
With the array of plant milks available today, there’s no shortage of fortified plant-based options to pour over cereal, add to a hot drink, or enjoy solo. Just make sure calcium is listed in the nutritional label and ingredients. Not all plant milks have added calcium. GoDairyFree.org has a helpful comparison of the calcium content in more than 100 brands of plant-based milks.
2. Calcium-set tofu
Tofu is often a go-to protein source for those on a vegan diet and can also be a rich source of calcium. For example, 100 grams of Nasoya tofu can provide around 176 mgs of calcium, according to the USDA. Similar to plant milk, not all tofu is a rich source of calcium, so be sure to read labels. Stevens says to make sure that “calcium” should be listed on the nutrition facts.
3. Low-oxalate leafy greens
“This is the most confusing category,” says Stevens. Leafy greens can be a rich source of calcium, but some are high in a compound called oxalates, which prevents calcium from being well-absorbed, she said. “Spinach, beet greens, swiss chard, and endive are particularly high in oxalates. They’re still nutritious foods but not a great source of calcium.” She recommends looking to low-oxalate greens for calcium, including bok choy, kale, broccoli, romaine lettuce, Brussels sprouts, collard greens, watercress, mustard greens, and turnip greens.
4. Beans, nuts, and seeds
There’s a wide variation of calcium in these foods from type to type, so be sure to read labels and look up amounts. Stevens says these foods provide smaller amounts of calcium but offer other important nutrients for bone health. For example, 1 oz. (or around 30g) of almonds provides about 75 mg of calcium, according to the USDA, and 100g of canned white beans contains about the same. White beans tend to be the highest in calcium, Stevens says. Stevens recommends opting for soaked or sprouted versions of beans, nuts, and seeds since soaking and sprouting increase the body’s ability to absorb calcium.
5. Calcium-fortified foods and juices
Examples of calcium-fortified foods include orange juice, breakfast cereals, some bread, and fortified snack bars. Another source is organic blackstrap molasses, which has 200 milligrams of calcium per tablespoon, or about 15 percent of your daily needs.
Aim for 3 cups worth of calcium-rich foods a day, especially the first three categories. For the leafy greens, “one cup” means “one cup after cooking.” So in the case of uncooked greens, that amount should be 2 to 3 cups, according to Stevens. “That, along with other calcium-containing foods like sweet potato, figs, oranges, blackstrap molasses, and corn tortillas, can allow vegans to consume enough calcium,” she says. Spreading your calcium intake throughout the day is best as the body can only absorb a certain amount at a time.
What Are the Symptoms of Calcium Deficiency?
Medically defined, calcium deficiency – or hypocalcemia – is a serious and potentially life-threatening condition. This “biochemical abnormality carries risks for serious errors in diagnosis and treatment," according to The BMJ. But there are less extreme forms of deficiency and the symptoms include muscle cramps, muscle aches and
Milder forms of hypocalcemia, or having a low level of calcium in the blood, can have numerous causes, such as vitamin D deficiency or thyroid issues. Routine blood tests can detect hypocalcemia before it becomes obvious, and it can typically be detected with a routine blood test.
- Muscle cramps
- Numbness and tingling in the fingertips, toes, and the perioral region
Treatment for hypocalcemia depends on the severity, but may be treated with supplements and sometimes with vitamin D. If the issue is due to an underlying condition, that must be treated.
Getting Enough Calcium on a Vegan Diet
Calcium is important for anyone following a vegan diet, especially for bone health. Some studies have found that vegans have a higher risk of fractures, for example, according to a study in BMC Medicine, and possibly a higher risk of osteoporosis, as well. But many consider this area to be inconclusive, or find that vegans can have good bone health, despite lower intakes of calcium. One study in Osteoporosis International found that “although vegans have much lower intakes of dietary calcium and protein than omnivores, veganism does not have an adverse effect on bone mineral density and does not alter body composition.”
Talk to your doctor or dietician if you have any concerns about not getting enough calcium, especially if you’re on medications, many of which can interfere with calcium absorption. Also, keep salt low and avoid smoking, both of which can interfere with calcium absorption. And be sure to get enough exercise.
Calcium-rich foods are the best source of calcium. Like many minerals, calcium levels in the body are best in a very narrow range. And as mentioned, taking a food-first approach is ideal. Add to that, a growing number of experts believe that a plant-based diet may actually be better for bone and overall health since plant-based diets can offer so many nutrients.
According to a review in Current Opinion in Endocrinology, Diabetes, and Obesity, “There is no evidence that a plant-based diet, when carefully chosen to maintain adequate calcium and vitamin D levels, has any detrimental effects on bone health. Theoretical findings suggest a long-term plant-based diet may reduce the risk of osteoporosis, through mechanisms that are currently speculative.”
Should You Consider a Calcium Supplement?
Since so many people don’t get the amount of recommended daily intakes of calcium – and that includes omnivores, vegetarians, and vegans in the U.S. and worldwide – many people turn to supplements for closing the gap, especially as they get older. Whether that’s a good idea or not, is a contentious area.
Research about the extent of calcium supplements’ helpfulness and potential harm is mixed. And getting too much calcium from supplements has increasingly come under fire in recent years. Many experts even question the safety of any calcium supplementation, according to the authors of a Clinical Interventions in Aging article, who write “We suggest that calcium supplementation should be prescribed and taken cautiously, accounting for individual patient's risks and benefits. Clearly, further studies are needed to examine the health effects of calcium supplementation to make any solid recommendations for people of different genders, ages, and ethnicities.”
Even the amount of calcium the body actually requires to function optimally is a controversial area, notes the authors of an article in the Journal of Internal Medicine. When it comes to supplementation, the best idea is to check with health professionals first, says Stevens. “Always speak to a doctor or dietitian before starting any supplements.”
If you do choose to take calcium supplements, you have a number of options. First off, check the ingredient list to make sure the source of calcium is vegan, and that there are no other non-vegan ingredients. “Calcium carbonate is cheap, easy to find, and absorbs well,” Stevens said. “Calcium carbonate should be about 40 percent elemental calcium.” It is likely to be vegan.
Elemental calcium is essentially the amount of pure calcium of the supplement. So, for example, 1,250mg of calcium carbonate contains 500 mg of elemental calcium.
“Calcium lactate is another option,” Stevens explains. Depending on the source of the lactate used, it is likely to be vegan as well but will vary depending on the products and where they are manufactured. “Calcium lactate should be about 13 percent elemental calcium.”
Another common calcium supplement is calcium citrate, which is about 21 percent elemental calcium, said Stevens. “This is typically considered easiest to absorb but is much more expensive,” she said.
“What supplement to choose depends on the person, any side effects they may experience and price point versus the amount of calcium,” Stevens said. As to whether the supplement is vegan, be sure to look at the ingredient list. You can also look for a “verified vegan” stamp to be sure and be sure to do research and contact the manufacturer with any doubts.
Most calcium supplements are best absorbed with food, so be sure to take supplements with meals.
How to make sure you are absorbing the calcium in your food
Calcium plays a vital role in the body's ability to absorb vitamin D, which is also essential for overall health. “Vitamin D helps the body absorb calcium and retain calcium,” says Stevens. There are very few natural food sources of vitamin D, vegan or otherwise,” she says. This is because humans evolved to get vitamin D from sun exposure, which is impractical for the vast majority of people.” Although some foods are fortified with vitamin D, many people will need a supplement and vitamin D3 is the preferred choice. If you are vegan, look for the vegan stamp, since it likely is not vegan unless specified. And, as with other supplements, always check with your doctor before starting a new routine.
Some plant-based foods are fortified with vitamin D (check the label) and this can be another way to ensure adequate intake. However, supplements are often needed for vegans and the general population, especially those who live farther north. Again, speak to a doctor about your supplement needs.”
Bottom Line: When starting a vegan diet, make a point to eat calcium-rich foods
Everyone needs calcium for overall health and bone health. If you are starting a vegan diet or going plant-based you may need to pay special attention to getting enough, but focus on getting it from food and consider being conservative about taking supplements.