If you eat vegan for ethical reasons, you have already made the hard decision. This guide is about the practical part: which nutrients people who eat vegan most often run low on, why plants supply less of some of them or let the body absorb less, how to build your days and weeks so the food side is covered, and which blood tests show whether it is working. Done carelessly, vegan eating can leave gaps that only show up years later. Done with a plan and regular blood work, it can be followed for the long term.
Smaller amounts, lower absorption, and gaps that take years to show.
02Each one: why it runs low, where to find it, which test.
03What goes into every day, in grams, and an example day.
04Pairing, soaking, fermenting, timing your tea and coffee.
05How much, and why variety matters more than with meat.
06What to test, how often, and what to discuss with your doctor.
Three things make vegan eating more demanding than eating some animal foods, and they add up over time.
Vitamin B12 occurs naturally only in animal foods. Iodine comes mainly from dairy, fish and eggs. The long-chain omega-3 fats EPA and DHA come from fish and algae, not from land plants. Plant foods contain little vitamin D.
The body absorbs about 5–12% of the iron in vegetarian eating, against 14–18% in mixed eating, which is why US guidance sets iron needs 1.8 times higher for vegetarians. Phytates in grains and legumes bind iron and zinc, so zinc needs rise as phytate intake rises. Plant protein is digested less completely than animal protein.
The body stores 1–5 mg of vitamin B12, about 1,000–2,000 times a day's intake, so a shortfall can take several years to show. Bones also change slowly: in a UK study of about 55,000 people followed for about 18 years, vegans had more fractures, with a hip-fracture risk about 2.3 times that of meat eaters. The gap was smaller in people with higher calcium and protein intake.
The German Nutrition Society (2024) and the Academy of Nutrition and Dietetics (2025) both describe well-planned vegan eating as adequate for healthy adults. Both conditions matter: well planned, and checked. The German Nutrition Society makes vitamin B12 supplementation a condition, and gives no recommendation for or against vegan eating in pregnancy, breastfeeding, childhood, adolescence or older age because the data are limited.
EU reference intakes are for adults (EFSA). "Test" is the blood test your doctor can use; they decide what is needed and read the results.
| Nutrient | Why it runs low on vegan eating | Where to find it, in grams | Test |
|---|---|---|---|
| Vitamin B12 EU reference 4 µg a day | Found naturally only in animal foods. Fortified foods vary a lot, and stores hide a shortfall for years. | Food cannot be relied on. Fortified soy drinks, cereals and nutritional yeast contain some, but amounts vary by brand: read the label. This is the one nutrient every vegan guideline says to supplement. | Vitamin B12 with MMA or holotranscobalamin (MMA is the most sensitive marker) |
| Iodine 150 µg a day (200 µg in pregnancy and breastfeeding) | Main sources are dairy, fish and eggs. Plant drinks contain little unless fortified. | Iodised salt instead of sea salt or rock salt for the salt you use (keep total salt moderate, about 5 g a day). Iodine-fortified plant drinks where available. Seaweed is not a reliable source: its iodine content ranges from 16 to 2,984 µg per gram, so it can give far too little or far too much. | Your doctor decides (TSH can stay normal while iodine intake is low) |
| Vitamin D 15 µg a day | Very few plant sources; made mainly in the skin from sunlight, which is weak in autumn and winter in Europe. | Midday sun from spring to early autumn (without burning). UV-exposed mushrooms and fortified foods contain some. Many health services advise everyone to consider vitamin D in autumn and winter; check that a supplement is suitable for vegans. | 25-OH vitamin D |
| Calcium 950 mg a day (1,000 mg at 18–24) | No dairy, and some greens high in calcium hold it in a form the body barely absorbs. | Calcium-set tofu, 100 g (check the label for calcium sulphate, E516, or calcium chloride). Calcium-fortified soy drink or soy yoghurt, 250 g. Kale, bok choy or broccoli, 100 g. Tahini, 15 g. Almonds, 30 g. White beans, 150 g. Spinach does not count: only about 5% of its calcium is absorbed, against about 50% from kale and bok choy. | Not reflected by blood calcium; your intake is what to track |
| Iron 16 mg a day (women before menopause), 11 mg (men, women after menopause) | Plant (non-haem) iron is absorbed less, and phytates and the polyphenols in tea and coffee reduce it further. | Lentils or beans, 150 g cooked. Tofu or tempeh, 150 g. Pumpkin seeds, 30 g. Oats, 50 g. Always with a vitamin C food at the same meal: red pepper 100 g, kiwi 75 g, orange 130 g, broccoli 100 g or lemon juice 15 g. | Ferritin and full blood count |
| Zinc women 7.5–12.7 mg, men 9.4–16.3 mg, rising with phytate | Grains and legumes are the main sources, and they also carry the phytate that binds zinc. The Nordic recommendations (2023) note that vegans are at risk of low zinc without fortified foods or supplements. | Pumpkin seeds, 30 g. Tempeh or tofu, 150 g. Chickpeas or lentils, 150 g cooked. Oats, 50 g. Cashews, 30 g. Hemp seeds, 30 g. Soaked, sprouted or fermented versions give more. | Zinc (plasma) |
| Omega-3 EPA and DHA 250 mg EPA + DHA a day | Plants supply only ALA, and the body turns little of it into EPA and DHA. In a review of 13 trials, flaxseed oil did not raise blood EPA and DHA, while microalgae oil raised them in every study. | For ALA, one portion a day: ground flaxseed 10 g, chia seeds 15 g, walnuts 30 g or hemp seeds 30 g, and rapeseed oil for cooking. EPA and DHA themselves come from algae oil: a topic for your doctor. | Omega-3 index (optional, ask your doctor) |
| Selenium 70 µg a day | Plant selenium depends on the soil, so the same food can contain very different amounts. | One Brazil nut (about 5 g) up to three times a week, not more: their selenium varies widely and too much is harmful. Wholegrains, legumes and mushrooms add smaller amounts. | Selenium, if your doctor advises it |
| Protein quality (lysine) 0.83 g per kg body weight a day, general reference | Plant protein is digested less completely, and grains, nuts and seeds are low in lysine. In a study of Danish vegans, lysine was the most often missed amino acid, mostly because protein came from only 3–5 foods. | A legume or soy food at every main meal (see section 05). | Not a blood test: track your intake |
| Choline 400 mg a day (480 mg in pregnancy, 520 mg breastfeeding) | The richest sources are eggs and meat. | Soybeans, tofu and soy drink, other legumes, quinoa, broccoli and Brussels sprouts. Most relevant before and during pregnancy and when breastfeeding. | Not routinely tested |
| Vitamin A 650 µg (women), 750 µg (men) a day | Plants contain beta-carotene, which the body has to convert, and conversion varies between people. | Orange and dark-green vegetables most days, with a little fat at the meal: carrot 80 g, sweet potato 150 g, butternut squash 150 g, kale or spinach 80 g. | Not routinely tested |
These are the food building blocks of a well-planned vegan day. Amounts are typical portions; your weekly meal planner scales them to your calories.
| Meal | What is on the plate |
|---|---|
| Breakfast | 50 g oats cooked in 250 g calcium-fortified soy drink, 10 g ground flaxseed, 100 g berries, 15 g pumpkin seeds. |
| Lunch | 150 g cooked lentils, 60 g quinoa (dry), 100 g red pepper, 80 g kale, 15 g tahini with 15 g lemon juice. |
| Snack | 1 orange (130 g) and 30 g almonds. |
| Dinner | 150 g calcium-set tofu or tempeh, 100 g broccoli, 70 g buckwheat (dry), 10 g rapeseed oil, cooked with iodised salt. |
The amounts that are right for you depend on your size, training and goal. The planner adjusts every portion to your own numbers.
The general EU reference is 0.83 g of protein per kg of body weight a day; people who train need more (your number comes from the macros calculator). Because plant protein is digested less completely, the meal planner adds about 10% to the protein target in vegan mode.
The bigger issue is lysine. Grains, nuts and seeds are low in it; legumes and soy are rich in it. That is why the checklist puts a legume or soy food at every main meal. Good lysine sources: lentils, chickpeas, beans, split peas, tofu, tempeh, soy drink and yoghurt, edamame, quinoa, pumpkin seeds and pistachios. Seitan is high in protein but low in lysine, so pair it with legumes rather than relying on it.
Some nutrients cannot be covered reliably by food on vegan eating. Those most often discussed are vitamin B12, vitamin D, iodine and the omega-3 fats EPA and DHA, and in some people calcium, iron, zinc and selenium. Which of them you need, and how much, depends on your food, your blood results and your health, so talk to your doctor before you take any supplement, and do your blood work first. More is not better: iodine, selenium, iron and vitamin D are all harmful in excess.
| Test | What it shows |
|---|---|
| Vitamin B12 with MMA or holotranscobalamin | B12 status. Serum B12 alone can look normal while stores fall; MMA is the most sensitive marker. |
| Ferritin and full blood count | Iron stores and anaemia. |
| 25-OH vitamin D | Vitamin D status. |
| TSH (and iodine, if your doctor advises) | Thyroid function. TSH can stay normal when iodine intake is low, so your doctor may assess iodine separately. |
| Zinc | Zinc status. |
| Selenium, omega-3 index | Optional; ask your doctor whether they are useful for you. |
The weekly meal planner builds vegan weeks around your own calories and protein, with legumes or soy at every main meal, a calcium base and an ALA portion every day, vitamin C with iron-rich meals and variety across the week. Your blood work, with your doctor, is what tells you it is working.
This page is nutrition coaching information, not medical advice. It does not recommend any product. Talk to your doctor before changing your eating, taking supplements or acting on blood results.
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