Calcium, Vitamin D, & Osteoporosis

Last week I started the 4-part series discussing potential complications with a plant based diet and how to prevent them. Today, we’ll continue with part 2 and discuss calcium and vitamin D and preventing osteoporosis.

A plant based diet is generally considered safe and an extremely healthy option. Following a balanced, mostly whole food plant based diet almost guarantees positive health outcomes with no negative side effects.

However, every single person is different; two people may be on the exact same diet, and one person’s body responds differently than the other one. It’s important to discuss all diet choices with your physician, consult a dietician, and get regular blood work and routine checkups.

What is calcium and vitamin D?

The most abundant mineral in the body, calcium is essential for every cell and to maintain strong bones. 99% of the calcium in our body is stored in our bones and teeth. Additionally, calcium plays a key role in blood clotting, muscle contraction, nerve contraction, and helping our hearts to beat properly.

The body loses calcium every day, and it cannot make more on its own. When we do not get enough calcium from the food we eat, our body takes the calcium from the teeth and bones. When this happens over time, it can lead to osteoporosis: where the bones become weak from calcium depletion and break more easily.

In addition to calcium, vitamin D also plays an important role in bone health by helping the body absorb calcium. Most vitamin D is obtained from sunlight, but some can be ingested with food and supplements.

The skin makes vitamin D in reaction to the sunlight, and then stores it in fat for later use. The amount of vitamin D produced by the skin depends on time of day, season, latitude and location, skin pigmentation, age, whether or not sunscreen is applied, and other factors.

Recommended Daily Intake

Calcium

• 1,000 mg daily: women aged 50 and younger; men aged 70 and younger
• 1,200 mg daily: women 51 years and older; men 71 years and older

Vitamin D

• 400-800 IU daily: women and men age 50 and younger
• 800-1,000 IU daily: women and men 51 years and older

Osteoporosis

The most common symptom of calcium deficiency over the long term is osteoporosis. Osteoporosis is characterized by low bone mass and structural deterioration of bone tissue. This leads to increased bone fragility and significantly increases the risk of bone fractures.

Bone is living tissue and is continuously “rebuilt.” Bones are broken down and replaced through reabsorption and depositing calcium into new bone. This absorption and deposition changes with age. In aging adults, loss of old bone exceeds creation of new bone, which results in bone loss. Post-menopausal women are at increased risk due to the decrease in estrogen.

Because vitamin D increases calcium absorption, inadequate vitamin D in the body can contribute to osteoporosis as well.

Additional risk factors for developing osteoporosis include being thin, inactivity, smoking, high salt intake, drinking excessive amounts of alcohol and caffeine, and having a family history of osteoporosis.

The dairy industry and the U.S. government

Before the coronavirus pandemic hit, dairy farmers in the U.S. were already seeing a 40% drop in prices over the last 6 years. This is largely due to the increase in large scale factory farming and increase in demand for plant based dairy alternatives (which is up 61% in the past several years). Additionally, since 1970, the number of U.S. dairy farmers has declined by 93% (to about 40,000 dairy farmers today.)

The United States government has an active role in assisting the U.S. dairy industry. But, they care less about Farmer Joe down the street and more about large factory farms. Not only are factory farms poorly regulated, but they also receive federal farm subsidies.  And most recently, bailout money during the pandemic.

Think about it this way: the American people have drastically reduced milk and dairy consumption. (There are literally hundreds of millions of pounds of surplus in cheese, butter, and milk). However, our tax dollars are continuing to be used to bail out the very industry that has seen a decline in demand. Just one example: in 2016, the USDA spent $20 million to buy excess cheese from dairy farmers.

As every vegan knows, it is extremely difficult to find products that do not contain milk. From potato chips to medications, dairy products are hidden everywhere. And this is by design. 

Large factory dairy farms spend millions of dollars each year paying off politicians to find new ways to promote dairy and increase milk consumption. One strategy is to hide milk in countless products (and often, these products should logically contain no dairy whatsoever.)

Lies of the Dairy Industry

The federal government is helping to sustain the dying dairy industry. Together, through lies and savvy marketing, they managed to convince us that milk is necessary for strong bones and healthy bodies. This myth has been disproven time and again.

We need to stop blindly following the government’s dietary guidelines and educate ourselves. They do not have our best interests in mind; their main concern is the almighty dollar. Thousands of studies exist that disprove everything the federal government is (quite literally!) trying to shove down our throats.

Lactose intolerance occurs because our bodies are not made to consume and digest cow’s milk. Among other things, studies have shown that dairy consumption can actually increase your risk of cancer. As if that weren’t enough, cow’s milk is pumped full of antibiotics, hormones, and chemicals. The meat and dairy industries are using the exact same marketing and sales tactics that the tobacco industry used for years. Let that sink in for a minute…

Preventing Osteoporosis

Most vegans eating a balanced, mostly whole food plant based diet consume an adequate amount of calcium and do not have issues with osteoporosis. However, many researchers agree that vegans are at increased risk for low calcium, but they also admit more research must be conducted. On the contrary, plenty of research already exists to advocate for a plant based diet.

Vegans with higher rate of fractures evidence:

• Study of more than 34,000 participants of meat eaters, vegetarians, and vegans found a slightly higher risk of fractures in vegans than the other populations.
• Compared with omnivores, this study found vegetarians and vegans had lower bone mineral density in the neck and spine, and vegans had higher fracture rates.
• Study of 177 individuals older than 65 years old found a strong correlation between dietary intake of legumes, eggs, meat, fish, vegetables, milk, grains, and olive oil and preservation of whole body bone mineral density. (The article did not specify the types of diets the participants ate.)
• Proving additional research is needed, this study concluded that the relationship between vegan diets, bone loss, and fracture rates are ambiguous.

Pro-Plant Based Diet evidence:

• A 12 year Harvard study of over 77,000 women found no evidence that drinking milk decreases rates of bone fractures or osteoporosis.
• Study of 96,000 participants lasting more than 2 decades found that greater milk consumption during teenage years was not associated with a lower risk of hip fractures in older adults.
• In relation to stress fractures, this study found no association between calcium and dairy intake and stress fractures; it did, however, find a correlation between adequate vitamin D intake and lower rates of fractures.
• A study of more than 100,000 participants in Sweden over 20 years found that a higher consumption of milk is not accompanied by a lower risk of bone fractures; on the contrary, the study found a higher consumption of milk may actually be associated with a higher rate of death.
• Dietary calcium intake is not associated with risk of fracture.
• Worldwide geographic study found rates of fractures and osteoporosis are increased with poor economic status, reduced winter sunlight (and vitamin D deficiency), and water fluoridation.
• Eating legumes at least once daily reduced risk of hip fractures by 64%; meat intake of 4 or more times per week was associated with a 40% reduced risk of hip fractures.
• Study concluded that bones are not negatively affected in young adults eating a plant based diet.

It has been suggested by some dietitians that the reason some vegans are not getting enough calcium in their diet is because they’re not eating a balance of healthy foods. Just because it’s a vegan diet, doesn’t make it healthy.

A balanced diet that meets daily intake requirements of calcium and vitamin D is key in achieving peak bone mass and reducing the rate of bone loss in the elderly.

Calcium and Vitamin D intake and the plant based diet

Food is the best source of calcium. Plant based foods rich in calcium include dark leafy green vegetables, broccoli, tofu, tempeh, almonds, seeds, and beans.

Calcium-rich foods include:

• Collard greens (1 cup = 360 mg)
• Broccoli rabe (1 cup = 200 mg)
• Bok choy (1 cup cooked = 158 mg)
• Swiss chard (1 cup = 102 mg)
• Kale (1 cup cooked = 100 mg)
• Mustard greens (1 cup = 165 mg)
• Legumes
• Soybeans (1 cup cooked = 175 mg)
• White beans (1 cup = 161 mg)
• Chickpeas (1 cup canned = 109 mg)
• Ancient grains (such as amaranth and teff, 1 cup cooked = 116 mg)
• Figs (2, dried = 65 mg)
• Broccoli (1 cup = 60 mg)
• Orange (1 whole = 55 mg)
• Raspberries (1 cup = 44 mg)
• Fortified plant milk and juice* (1 cup = 300 mg)
• Tofu (4 oz = 205 mg)
• Tahini (2 tablespoons = 130 mg)
• Almonds (¼ cup = 97 mg)
• Almond butter (2 tablespoons = 111 mg)
• Chia seeds (1 tablespoon = 76 mg)
• Flaxseed (1 tablespoon ground = 18 mg)
• Barley (1 cup = 61 mg)

* Before use, soy milk (and other calcium fortified drinks) needs to be shaken well since the calcium can settle on the bottom of the container.

While spinach does contain calcium, it also contains high levels of oxalic acid, which reduces the body’s ability to absorb calcium.

Vitamin D and sun exposure

Would you be surprised if I told you most orange juice isn’t vegan? Well, it’s not. Typically, vitamin D3 is derived from lanolin, a natural oil in sheep’s wool. Additionally, these juices often have added omega-3s, which come from fish oil and gelatin. 😝

Vitamin D intake from food sources is rare, but some plant based milks, juices, and cereals are fortified with vitamin D. It is difficult to get the required amount of vitamin D from food alone, so daily sun exposure or dietary supplements are necessary. 

Although a multitude of factors are taken into account, most researchers recommend approximately 5-30 minutes of sun exposure at least twice per week. This sun exposure should be to the face, arms, legs, or back without sunscreen between the hours of 10 a.m. and 3 p.m. (Always consult with your doctor for guidance.)

It is also worth noting that UVB radiation does not penetrate glass, so indoor sun exposure through a window does not produce vitamin D.

Eat a well-balanced diet

Calcium intake can be adequate in a well-balanced plant based diet. The key to bone health is adequate calcium intake, regardless of the dietary source. And given what we know about dairy and animal production, a plant based diet is the best option.

In addition to adequate calcium and vitamin D intake, regular exercise is vital to keeping bones strong. Active people tend to keep calcium in their bones, while those living a more sedentary lifestyle lose calcium in their bones.

Recognizing that each person is unique, it’s important to consult a registered dietician for your individual dietary needs.

What is something that has surprised you about eating a plant based diet? Post to the comments below, and let me know of any questions you might have!