I have a confession. Animal foods contain many important nutrients. That is not really a controversial statement, and any honest vegan would admit it. If we decide to eat less animal products and do not replace those nutrients, we can develop deficiencies. So the important question is, can you prevent these deficiencies while eating a plant-based diet? Definitely. With a well-planned diet, we can easily get all of the nutrients our body needs in sufficient doses. In this post, I will summarise the nutrients that vegans should focus on and provide practical tips for how to prevent these deficiencies.
Can it really be healthy to not consume animal products?
The Academy of Nutrition and Dietetics claims that plant-based diets, such as well planned vegan and vegetarian diets, are suitable for all stages of life. This definition includes pregnant women, breastfeeding women, babies, young adults, older people, and athletes 1. Of course, the well planned part is really important. If we eat a lot of vegan processed foods and sweets, if we do not eat a wide variety of whole plants, or if we do not consume the supplements we need, our health can suffer. A vegan diet can be healthy, but it is not automatically healthy simply by virtue of being vegan.1
Vegans are not the only population that need to properly plan their diet. If we follow any diet, it is important plan it appropriately. People eating an omnivorous diet can also develop deficiencies. So it is not only vegans who need to plan and learn a little about nutrition. We can all benefit from learning about the nutrients our bodies require and the foods that contain them. Once you have this information and try to put it into practice, it can be difficult at first, but the more you do it the more automatic it becomes. We became accustomed to the diet we are eating now gradually throughout our lives, and as we learned more and more, eating this way became automatic. Similarly, if you follow a more plant predominant diet for some time, it will become easier and more automatic.
The Academy of Nutrition and Dietetics’ position statement on vegetarian diets was published in 2016. We are still waiting for this academy’s next more updated version of their position statement. Since one academy is not representative of nutrition as a whole, let’s discuss some of the nutrients we need to look out for on a plant focused diet using other forms evidence.
Vitamin B12
Viitamin B12 has many important roles in the body. For example, it has a role in making blood cells and nerve cells as well as regulating metabolism.2,3 Animal products are high in B12 and as far as we know, plants do not contain forms of B12 that humans can utilise. Various bacteria make B12 and if an animal unintentionally eats water, dirt, or faeces that contain these bacteria, then they ingest the vitamin. In addition, bacteria in the intestines of some animals can produce vitamin B12 directly.4 Even animals raised in factory farms can eat a cobalt-deficient diet and hence require cobalt or B12 supplements. However, cows and sheep that eat only grass can naturally consume more cobalt and B12.5 B12 supplements are actually produced by cultivating bacteria.6
Vegans and vegetarians can develop vitamin B12 deficiency.7 Vitamin B12 is the only essential nutrient that we cannot get from eating plants alone. That is why vegans must take at least a vitamin B12 supplement. If you only want to buy one supplement, I strongly recommend taking vitamin B12. Women who are pregnant or breastfeeding should particularly focus on B12 intake, to prevent neural tube defects in the foetus.8,9
Fortunately, many of us can access and purchase cheap B12 supplements. Multivitamins also usually contain enough B12. These days, many plant-based foods are supplemented with B12. For example, plant-based milks such as soy milk, oat milk, or almond milk, meat alternatives, and nutritional yeast typically contain B12. However, these foods are not always supplemented with B12, so we should check the ingredients and nutritional information on the packaging. Furthermore, if we do not eat these supplemented foods every day, taking a B12 supplement is a safer approach.
Studies that have concluded that B12 levels within vegans were too low did not test only vegans who were taking B12 supplements. Of course, vegans who do not supplement become B12 deficient. However, if you take supplements, deficiency is unlikely.10
Adults should consume 2.4 μg of B12 daily, pregnant or breastfeeding women should consume 2.6-2.8 μg of B12 per day, and children should consume bet 0.4-2.4 μg of B12 per day depending on age.8 Even people eating an omnivorous diet should take a B12 supplement as they get older because we absorb B12 less effectively with age.11 Taking a smaller daily dose of B12 is more effective than taking a larger weekly dose, as more is absorbed. However, if you take a large dose all at once, the absorption efficiency is lower.12 Hence, vegans should take a higher dose than the minimum recommendation for omnivores.2 For example, taking 300-400 μg of B12 daily is about right.2
If you choose to buy B12 supplements, you will come across several different types. Cyanocobalmin is a form of B12 that is safe even though it has cyanide in the name. This is the most common and most tested type of B12 supplement. Methylcobalamin is another safe form of vitamin B12, but the dosage required is different from cyanocobalmine.2,13 If you have the MTFHR gene or kidney disease, methylcobalmin may be more suitable.14-16
Iron
Iron plays an important role in the body. For example, the body produces the protein hemoglobin that transports oxygen in the blood using iron. Meat contains heme iron, which humans can absorb well. However, plants contain non-heme iron which is less well absorbed.17 Hence, vegans can develop iron deficiency. Vegan women, particularly before menopause, are more likely to develop iron deficiency.18 So does following a plant-based diet guarantee that you will develop an iron deficiency? Not at all. By consuming iron supplements, iron-fortified multivitamins, and plant-based sources with sufficient non-heme iron, we can realistically prevent deficiencies. Adult males should aim for a daily intake of 8 mg of iron, while adult females before menopause should consume 18 mg. Pregnant women should aim for a daily intake of 28 mg of iron. Many whole grains, legumes, plants, nuts, seeds, and leafy greens are rich sources of iron.19 For example, soybeans, lentils, peas, peanuts, tahini, pumpkin seeds, sesame seeds, spinach, and seaweed are high in non-heme iron.2 Vitamin C, onions, and garlic increase iron absorption, however, tea lowers iron absorption. So, by adding lemon juice or plants rich in vitamin C to your meals, along with onions or garlic, you can enhance iron absorption. If we want to drink tea, it is better to have it between meals rather than with a meal.20,21
Iodine
Iodine is needed to make thyroid hormone. Vegans can potentially develop iodine deficiency.22 Iodized salt is widely available, and sea vegetables like nori and other seaweeds also contain iodine. However, the iodine content in seaweed varies depending on where it’s cultivated, so simultaneous supplementation is a safe approach. Consuming 150 μg of iodine daily is sufficient. It’s important not to consume too little nor too much iodine. Balance is key.2,13
Vitamin D
Vitamin D plays many important roles in the body. Sunlight initiates the process of vitamin D production inside our bodies. However, for those who don’t get ample sun exposure outdoors daily or live in regions significantly north or south of the equator where sunlight is scarce, taking vitamin D supplements is crucial.23 Especially in winter when sunlight is limited, supplementing with vitamin D is a safe approach. Skin tone also matters. Darker skin leads to lower vitamin D production.24 Regardless of whether one follows an omnivorous or vegan diet, vitamin D deficiency can be a concern. Fortunately, affordable vitamin D supplements are readily available. Plant-based fortified milks are also sources of vitamin D. However, it is worth noting that vitamin D3 supplements sometimes come from animal-derived products like lanolin (the wax on sheep’s wool).25 Vitamin D2 supplements are vegan, and there are vegan varieties of vitamin D3 sourced from lichen. So, it is important to check this before purchasing a supplement. Because vitamin D2 has lower effect on the body’s vitamin D stores compared to vitamin D3, higher doses are recommended. A daily intake of at least 1000 IU (international units) of vitamin D2 is advised.13
Calcium
Why is drinking milk important for our bodies? Most people would likely answer ‘for our bones.’ We’ve been well-exposed to this message through marketing and social conditioning. Milk is indeed rich in calcium. However, milk is not the only source of calcium. In fact, the calcium found in cow’s milk originally came from the plants that the cow consumed.
It is recommended that adults take 1000 mg of calcium daily.26 By drinking two cups of calcium-fortified plant-based milk daily, we can obtain sufficient calcium. Whether we drink calcium carbonate fortified soy milk or dairy milk, we absorb nearly the same amount of calcium. However, if we consuming soy milk fortified with tricalcium phosphate, we absorb 17% less calcium compared to dairy milk.27 So, if you are drinking plant based milk supplemented with tricalcium phosphate, you should consume a slightly larger dose. The supplemented calcium may settle at the bottom of plant-based milk containers, so it is good practice to thoroughly shake the bottle before drinking. Apart from plant-based milks, kale, broccoli, soy, cabbage, oranges, almonds, sesame seeds, and white beans are sources of biologically available calcium.13,28,29
Importantly, calcium is not the only crucial nutrient for building strong bones. Alongside calcium, vitamin D, protein, vitamin B12, and engaging in resistance exercise is also vital.30 Merely consuming foods rich in calcium is not sufficient, we also need to ensure we are getting an adequate intake of other nutrients. Additionally, without regularly doing activities like lifting weights or body weight training, we risk weakening our bones. Therefore, rather than solely focusing on calcium for bone health, it’s essential to concentrate on all key aspects together.
Omega-3
Omega-3 fatty acids are a special type of fat. Vegans may have lower levels of DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid).31 DHA and EPA, the most crucial forms of omega-3, are typically derived from seafood. ALA (α-linolenic acid), on the other hand, comes from plants. ALA rich plants include flax seeds, chia seeds, and walnuts.32 Fortunately, the body can convert ALA into DHA and EPA. Our bodies convert about 5-10% of ALA into EPA and 2-5% of ALA into DHA. So, consuming 2-4 g of ALA daily may be enough to reach our DHA/EPA requirements. However, excessive consumption of a type of omega-6 fat called LA (linoleic acid) can hinder the conversion of ALA into DHA or EPA. LA is found in many plant oils and the optimal ratio of ALA to LA in our diets is around 1:4. However, this does not imply that plant oils are inherently bad for us. Instead, reducing the consumption of processed foods and oils high in LA, and substituting them with alternatives like olive oil, which is low in LA and high in ALA, can help to reduce omega-6 intake. Depending on how much LA rich plant based foods we consume, supplementing with DHA and EPA can be important.31 For those who do not consume seafood regularly, a common recommendation is supplementation with 500-1500 mg of EPA and DHA.
DHA and EPA originally come from algae. Fish acquire these fats by consuming algae, which then become a part of their body. To attain sufficient levels of DHA and EPA in fish farms, the fish are often fed fishmeal or fish oil. However, this practice is unsustainable. Obtaining DHA and EPA directly from algae is more efficient.33 Fortunately, we can purchase algae oil supplements. The bioavailability of DHA in algae oil and in salmon is equivalent.34,35
While EPA and DHA are not considered essential nutrients, they can contribute to our overall health. The benefits of omega-3 supplementation remain a debated topic, and current research has not strongly demonstrated any significant long-term health benefit of consuming EPA and DHA supplements. The seafood and fish oil supplement industry has heavily marketed the importance of DHA and EPA for heart and brain health. Until better research emerges, taking DHA and EPA supplements may be a safe approach. However, due to the importance of omega-3s for foetal neurological development, it is crucial for pregnant vegan women to consume algae based omega-3 supplements. Pregnant women who incorporate omega-3 supplementation may reduce the risk of premature birth.36
A meta-analysis of randomised control trials concluded that consuming omega-3 supplements did not significantly reduce overall mortality, mortality attributed to cardiovascular disease, incidences of cardiac arrest, or the onset of stroke.37 However, another meta-analysis of randomised control trials concluded that individuals with cardiovascular disease had a lower likelihood of mortality, cardiac arrest, and stroke if they consumed omega-3 supplements.38 A more recent meta-analysis of randomised control trials formed similar conclusions.39 Furthermore, another meta-analysis of randomised control trials reported an 8% reduction in the incidence of cardiac arrest and a 7% decrease in mortality attributed to cardiovascular diseases with the consumption of omega-3 supplements.40 It remains uncertain if prolonged, continued intake of omega-3 supplements over a longer duration may yield more substantial effects.
A meta-analysis of prospective cohort studies reported that consuming 1.4 g of ALA daily was associated with a 9% lower incidence of coronary artery disease. Furthermore, for every additional gram of ALA consumed daily, there was a 12% reduction in mortality attributed to coronary artery disease.41 Another meta-analysis of prospective cohort epidemiological studies found that individuals with higher blood concentrations of EPA and DHA had a 15-18% lower overall mortality rate. Similar benefits were also observed in mortality rates related to cardiovascular diseases and cancer. However, individuals with higher blood concentrations of ALA did not seem to derive any benefits.42 A meta-analysis of randomised control trials concluded that consuming EPA and DHA had minimal to no effect on overall mortality and cardiovascular disease. They also suggested that consuming ALA may help in reducing cardiovascular events.43
As you can see, consuming EPA and DHA supplements either have no effect or a minimal effect. Due to these somewhat inconsistent results, further research is needed before drawing more concrete conclusions about EPA and DHA supplementation. Consistently incorporating EPA and DHA throughout one’s life may help in preventing certain illnesses, but it appears less effective in treating them once they have developed. Besides heart health, omega-3s may also have some potential benefits for the brain and cognition. However, more research is warranted in this area.44-46
So, the decision to consume EPA and DHA supplements is a personal one. However, if you are pregnant, taking omega-3 supplements is strongly recommended. In Western countries, many people do not consume a lot of seafood, so they may benefit from these supplements as they are not getting enough EPA and DHA through their diet. Personally, I take one algae oil supplement daily. However, currently, algae oil supplements can be a bit expensive. I anticipate that as algae oil production becomes more widespread, prices will come down. At the very least, consuming 2 tablespoons of flax seeds, 2 tablespoons of chia seeds, or about 4.5 walnuts daily should be enough to intake enough ALA. These seeds and nuts are relatively inexpensive. Including flax seeds and chia seeds in oatmeal or smoothies is both delicious and convenient. Chia seeds should be soaked in water and flax seeds should be ground (into flax meal) before eating to allow the ALA to be absorbed. While other plants do contain ALA, they generally have lower concentrations compared to these seeds and nuts.
Zinc
Zinc is crucial for growth, protein synthesis, DNA formation, wound healing, and immune function.2 Vegans may have lower zinc levels, potentially leading to deficiency.47 Many varieties of whole grains, tofu, legumes, nuts, and seeds are rich in zinc. Cooking, fermenting, soaking, or sprouting plant foods can enhance zinc absorption.48 Similar to the discussion on iron, adding garlic or onions to meals can also increase zinc absorption.21 Men should aim for a daily intake of 21 mg of zinc, while women should aim for 12 mg. Pregnant and lactating women should aim for 16-18.5 mg of zinc daily.48
Selenium
Selenium is important for DNA synthesis, thyroid hormone production, reproduction, and cellular protection.2 Vegans may be at risk of selenium deficiency.49 Eating one or two Brazil nuts per day is sufficient to meet our selenium requirements.50 It is important not to consume excessive amounts of selenium, as it can slightly increase our overall risk of mortality. Hence, it is recommended to not consume too many Brazil nuts daily. Selenium is also found in bread and grains.51
Multivitamins
Preventing these nutrient deficiencies may seem inconvenient at first, but as you make it a regular part of your routine, it becomes as automatic as riding a bike. Transitioning to a plant-based lifestyle is becoming more and more easy and accessible. If you have read this far, you might have noticed a pattern. The most efficient way to prevent deficiencies is through supplementation. If you prefer not to meticulously analyse and plan your food or don’t want to buy and consume many different supplements at a time, you can opt for a multivitamin. Nowadays, there are multivitamins designed specifically for vegans that contain the mentioned nutrients in appropriate dosages. This is super convenient. Each day, I simply take one multivitamin tablet and one algae-based omega-3 tablet.
You can purchase these supplements at pharmacies or online. For me, ordering them in bulk online seems to be the easiest approach. I do not want to endorse any specific company or product. However, to show you an example of a suitable supplement, this link and this link are the supplements I take. I spend about 50 cents daily on these supplements, which is relatively affordable. This post is not sponsored content. I do not earn any money from any supplement brand. I simply aim to provide information and helpful tips. Feel free to look for other brands! However, I recommend finding supplements with similar dosages.
Do supplements actually increase our body’s stored levels of nutrients? A cross-sectional study conducted in Switzerland concluded that with a well-planned diet and supplementation, deficiencies can be prevented on a vegan diet. Some vegans had deficiencies in iron, zinc, iodine, and vitamin B12. However, it was also noted that some people eating an omnivorous diet also had deficiencies in iron and iodine.10 Therefore, whether vegan or non-vegan, we all need to focus on consuming enough of the essential nutrients. Vegan athletes can also obtain sufficient vitamin B12, vitamin D, and iron.52 It can also be safe for pregnant women to follow a vegan diet. In such cases, it is crucial to ensure an adequate intake of iron, calcium, vitamin B12, and vitamin D.9,53
It is a good idea to visit a doctor and get a blood test both before and a few months after starting a new diet. A blood test can help identify any nutrient deficiencies, allowing allowing you to adjust your diet and ad supplements if needed.
Are supplements a bad thing?
Some people claim that a vegan diet is deficient or unnatural because vegans need to take supplements. This argument is an example of the naturalistic fallacy. What is natural is not always healthy, and what is unnatural is not always unhealthy. The consumption of supplements is not inherently bad, as they are simply a form of nutrition. The most important thing is that we consume sufficient nutrients, regardless of whether they come from food or supplements. These days many of us can easily access supplements, and the fact that supplements were not consumed in the past is irrelevant to our current situation. Furthermore, not only vegans but also omnivores can benefit from evidence-based supplementation. For example, many foods are already fortified with essential nutrients to benefit public health. Milk, cereal, juice, salt, flour, bread, and water are examples of foods that are fortified with important nutrients. Personally, I much prefer obtaining nutrients from plants and supplements rather than feeding plants and supplements to animals and slaughtering them. This is both more efficient and more ethical. For those who wish to avoid supplements as much as possible, it is possible to get all necessary nutrients from plants, with the exception of vitamin B12.
Conclusion
We easily and conveniently prevent nutrient deficiencies while eating a plant predominant diet. If we develop awareness of the nutrients we need and the foods that contain them, obtaining these essential nutrients becomes automatic. Aside from vitamin B12, we can obtain all essential nutrients through plant-based sources, but taking supplements can be a safe approach. These essential nutrients include iodine, vitamin D, calcium, iron, zinc, and selenium. While there is some debate about the need for omega-3 supplements, a safe approach for heart and brain health could be to consume DHA and EPA supplements. Opting for algae-based omega-3 supplements, rather than consuming seafood or fish oil tablets, is both more sustainable and ethical. An alternative approach is to include plenty of ALA-rich seeds and nuts in our diet. Taking a multivitamin with the recommended daily amounts of essential nutrients is the easiest and most cost-effective way to ensure we meet our nutritional needs.
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