Of all the nutrients that vegans must deal with, calcium probably demands the most effort. Sure, other nutrients require attention too, but most are quite easy to obtain. For instance, your needs for Vitamins D and B12 are easily covered by popping supplements every couple of days. As for protein, many vegan foods are loaded with it, plus you can always turn to vegan protein powder if you fall short. Omega 3 needs are reliably met with a daily tablespoon of ground chia, plus perhaps a capsule or two of vegan DHA/EPA.
Meeting your calcium needs requires more effort. That’s because many foods contain virtually no calcium, and most people don’t supplement for this nutrient. Supplementing is therefore frequently a wise choice, both for vegans and non-vegans.
Dairy Industry Duplicity
Sometimes people on both sides of an argument get their main points spectacularly wrong. That’s especially true in the calcium dispute that rages dairy interests and vegans. The dairy people seem at times deliberately misleading, whereas the vegans also trot out their share of bogus claims.
Using the classic “get ’em while they’re young” strategy, the dairy industry has put calcium needs for growing children and adolescents at the very center of its marketing. By using fear-based messaging that there is a “calcium crisis,” they’ve tricked the public into believing that dairy products are the best source of this nutrient. But it turns out that many vegan foods surpass dairy as a source of calcium.
On top of this, the dairy marketing boards never seem to volunteer the fact that the vast majority of people have problems digesting milk. About 65 percent of the world’s adults are lactose intolerant. And that figure is much higher among people of African and Asian descent—around 99 percent of adults of Chinese descent are lactose intolerant.
Vegan Calcium Needs: Setting the Record Straight
Unfortunately, vegan advocates are scarcely better than dairy lobbyists when it comes to accurately discussing calcium. A number of vegan books and websites assert that dairy is, in reality, a poor source of calcium. The claim is that the substantial amount of protein found in dairy products inhibits calcium absorption. People making this argument often reference charts showing the rates of milk drinking and hip fracture in various countries. These charts present the data in a way that suggests dairy products cause increased rates of hip fracture.
This entire line of thinking has, however, been thoroughly debunked. Studies indicate that high protein intake probably doesn’t have much impact on bone health. In fact, protein has also been shown to improve calcium absorption. As for the hip fracture argument, there are confounding factors that make pointing to this statistic dishonest. For example, hip fracture rates are highest in high-latitude locations with lots of ice on streets and sidewalks—and ice is of course closely associated with falls. On top of that, the lack of winter sunlight in high latitude areas tends to reduce vitamin D levels in many people, resulting in diminished bone health.
As we’re about to see, it’s nonsense to assert that dairy plays an irreplaceable role in ensuring adequate calcium consumption. But the position some vegans take regarding calcium is equally problematic. The reality is that it’s quite possible for a daily milk drinker to see her calcium status decline by going vegan. This is especially likely if she doesn’t add calcium-rich vegan foods to replace the dairy products she has stopped consuming.
How Do Vegans Get Calcium?
No specific calcium intake recommendation is suitable to everyone. Absorption rates differ from person to person. Setting the target level for any nutrient is an inexact science. But an informed guess is certainly more helpful than no guess at all. So when governments and nutritional councils set targets they try to err on the high side. They seek to set a guideline that meets the needs of more than 95 percent of the population.
The ideal level of calcium intake varies across different ages, and is highest during adolescence and old age. The U.S. Institute of Medicine sets recommendations for calcium at 1300 mg. for people age nine to eighteen, 1000 mg for adults, and 1200 mg. for women over fifty and men over seventy. These numbers are probably not exactly right, but they’re the best estimates we currently have. It’s therefore wise to plan your diet so that you hit these recommendations.
What are the Best Vegan Calcium Sources?
Now that we know that you need something like 1000 to 1300 milligrams of calcium each day, reaching this number involves simple arithmetic. Here is what various calcium-rich vegan foods deliver:
- Tofu (½ Cup or 4.5 ounces. Must have calcium sulfate listed in the ingredients): 430 mg (90 Calories)
- Soy Milk (1 Cup, calcium-fortified, unsweetened): 300 mg. (79 Calories)
- Collard greens (1 Cup, cooked): 268 mg. (63 Calories)
- Mustard greens (1 Cup, cooked): 165 mg. (36 Calories)
- Bok Choy (1 Cup, cooked) 158 mg. (20 Calories)
- Kale (1 Cup, chopped, cooked): 94 mg. (36 Calories)
- Black Beans (1 Cup, canned) 84 mg. (218 Calories)
- Tahini (1 Tablespoon, roasted): 64 mg. (89 Calories)
- Broccoli (1 Cup, chopped, cooked): 31 mg. (27 Calories)
For comparison, whole milk supplies 276 mg. calcium per cup, and contains 149 calories. So you can see that cows’ milk is an excellent source of calcium, but fortified soy milk is too. And on a per-calorie basis, bok choy contains more than four times the calcium as whole cows’ milk.
Meeting Your Calcium Needs as a Vegan
The calcium figures above are useful to keep in mind, but they’re also a lot to remember. With many calcium-rich vegan foods, the limiting factor of how much you’d want to eat in a day isn’t related to calorie content, but instead to how bulky these foods are.
For instance, kale contains a great deal of calcium per calorie. The trouble is that this calcium is accompanied by a whole lot of bulk. If you tried to satisfy your daily calcium needs solely through raw kale, you’d need to eat ten cups a day. You’d have to be deranged to attempt that! Even worse would be the prospect of trying to meet your needs through black beans alone. Just imagine what eating more than ten cups of beans every day would do to your digestion.
Tofu and Soy Milk Can Contain Loads of Calcium
There’s no question that you could get sufficient calcium by eating some combination of beans, greens, and broccoli. But your diet might feel restrictive. And it would also be bulkier than many people prefer. So instead, consider adding calcium-fortified soy milk or some calcium-set tofu to your daily diet.
Together, tofu and vegan milks can transform the task of getting sufficient calcium from tricky to easy. For example, you can meet half your daily calcium needs by drinking a cup of soy milk with breakfast, and then including a half-cup of tofu in your lunch. From there, a relatively small amount of beans and greens can put you over the top.
If you’re relying on tofu as a calcium source, always make sure the label lists calcium sulfate in its ingredients. Otherwise it’s not a good source of calcium. Likewise, check the nutrition panel of your vegan milks to ensure it contains plenty of calcium (at least fifteen percent of your RDA per serving). Some people object that eating calcium-set tofu and fortified soy milk isn’t “natural,” but this is a baseless concern. Such calcium is as well-absorbed and high quality as the calcium from dairy products or any other source.
Oxalates
Every variety of leafy green contains a substantial amount of calcium. But there’s an important caveat to keep in mind: several popular greens contain substantial amounts of oxalates (oxalic acid). This substance interferes with calcium absorption. Oxalates won’t cancel out all the calcium your greens contain, but they can prevent you from absorbing most of it.
So if you’re eating greens in order to boost your calcium intake, you should avoid spinach, chard, and rhubarb—all of which are rich in oxalates. Note also that boiling oxalate-rich greens causes some of the oxalic acid to leach out into the water. This significantly improves calcium absorption, assuming you discard the cooking water and don’t use it as soup stock.
Three greens in particular—mustard greens, bok choy, and kale—are all low in oxalates, and are therefore superb sources of calcium.
Vegan Calcium Supplements
Some people struggle to get sufficient calcium through food alone. In these cases, supplements offer an easy way to close the gap. Depending on the brand (check the label), just one tablet can give you a whopping 500 to 1000 mg. of this nutrient, enabling you to instantly elevate your intake from inadequate to excellent. Deva Nutrition manufactures an affordable vegan supplement that contains a big dose of both calcium and magnesium.
But don’t just start gobbling supplements without paying heed to your total calcium intake. Too much calcium can easily cause kidney stones (which are dangerous and excruciating to pass, sometimes necessitating surgical removal). So make sure that your combined calcium intake from food and supplements doesn’t exceed 1300 milligrams per day.
Bone Health for Vegans
Articles about bone health tend to focus on calcium consumption, but there are two other crucial factors to consider: vitamin D and exercise.
Bones contain specialized cells called osteoblasts and osteoclasts, which work together to maintain bone strength and prevent brittleness. Just like you need a steady flow of fresh oxygen entering your bloodstream, the same is true of the minerals that enter and leave your bones. Every day, osteoclasts break down a tiny portion of your skeleton. In the process, osteoblasts take calcium from your blood and assemble it into a fresh new bone matrix. Increasing the number and function of your osteoclasts and osteoblasts strengthens your bones and makes them less prone to breakage.
As you can see, calcium intake is only part of the story where bone health is concerned. So be sure you’re taking in adequate vitamin D. This nutrient is essential for proper osteoclast formation, a vital component in bone health.
The Importance of Exercise
Regular weight-bearing exercise also strengthens bones by improving the performance of osteoblasts and osteoclasts. Weight lifting of any kind obviously qualifies as weight-bearing exercise. That’s true whether you’re doing 200 kilogram bench presses or toying around with 2 kilogram dumbbells.
Not into weights? Cheap portable resistance bands deliver the same bone health benefits as weight training. There are numerous other types of weight bearing exercise. These include: walking, hiking, jogging, climbing stairs, tennis, and dancing.
The two most popular exercises that are not considered weight-bearing are swimming and bicycling. While these can work wonders in terms of aerobic conditioning, they won’t improve bone health.
If the connection between exercise and bone health interests you, check out my Guide to Vegan Fitness. You’ll discover how easy it is to get more physically active, and unlock substantial health benefits.
Three Crucial Takeaways
If you ignore calcium and never give your intake a thought, you’re likely to suffer poor bone health later in life. But you can easily reduce these risks with just a little reading and attention. Vegans can protect their bone health by following these recommendations:
- Consume 1000 to 1300 milligrams of calcium each day. If you can’t get all of this through food, then take a supplement. But don’t surpass 1300 milligrams total calcium consumption (food plus supplement) per day.
- Spend a half hour or more each day doing some type of weight-bearing exercise.
- Make sure to get adequate vitamin D. For most vegans, especially those in temperate climates, that means taking a vitamin D supplement.
Vegans and omnivores alike often pay insufficient attention to calcium, a fact reflected by the millions of bone fractures occurring due to osteoporosis each year. Fortunately, a well-planned vegan diet, including fortified foods and calcium supplements if necessary, can provide excellent calcium status. That, coupled with sufficient exercise, will help ensure good bone health later in life.