While a diet based exclusively on plants may have some health benefits, it may put some people at a higher risk of nutrient deficiencies.
This is especially true when vegan diets are not well planned.
1. Legumes
Vegans avoid animal-based sources of protein and iron, such as meat, poultry, fish, and eggs.
Therefore, it’s important to replace these animal products with protein- and iron-rich plant-based alternatives such as legumes.
Beans, lentils, and peas are great options that contain 10–20 grams of protein per cooked cup.
They’re also excellent sources of fiber, slowly digested carbs, iron, folate, calcium, potassium, zinc, antioxidants, and other health-promoting plant compounds (1Trusted Source, 2Trusted Source).
However, legumes also contain a fair amount of antinutrients, which can reduce the absorption of minerals (3).
For instance, iron absorption from plants is lower than that from animal sources. Similarly, vegetarian diets seem to reduce zinc absorption by about 35% compared with those containing meat (4Trusted Source, 5Trusted Source, 6).
It’s advantageous to soak, ferment, or cook legumes well, because these processes can decrease the amounts of antinutrients (7Trusted Source, 8Trusted Source).
To increase your absorption of iron and zinc from legumes, you may also want to avoid consuming them at the same time as calcium-rich foods. Calcium can hinder the absorption of these nutrients if you consume it at the same time (9Trusted Source).
In contrast, eating legumes in combination with vitamin C-rich fruits and vegetables can increase your absorption of iron (10Trusted Source).
2. Nuts, nut butters, and seeds
Nuts and seeds are great additions to any vegan refrigerator or pantry. That’s in part because a 1-ounce (28-gram) serving of nuts or seeds contains 5–12 grams of protein.
This makes them a good alternative to protein-rich animal products.
In addition, nuts and seeds are great sources of iron, fiber, magnesium, zinc, selenium, and vitamin E. They also contain a good amount of antioxidants and other beneficial plant compounds (11Trusted Source).
Nuts and seeds are extremely versatile. You can eat them on their own or work them into interesting recipes such as sauces, desserts, and vegan cheeses.
Try to choose unblanched and unroasted varieties whenever possible, since nutrients can be lost during processing (12Trusted Source).
Favor nut butters that are natural rather than heavily processed. These are usually free of the oil, sugar, and salt often added to some popular varieties.
3. Hemp, flax, and chia seeds
These three types of seeds have special nutrient profiles that deserve to be highlighted separately from the previous category.
For starters, all three contain larger amounts of protein than most other seeds.
One ounce (28 grams) of hemp seeds contains 9 grams of complete, easily digestible protein — and up to 50% more protein than some other seeds (13Trusted Source).
Research also shows that the fats found in hemp seeds may be very effective at diminishing symptoms of premenstrual syndrome and menopause (14Trusted Source, 15Trusted Source, 16Trusted Source).
They may also reduce inflammation and improve certain skin conditions (17Trusted Source).
For their part, chia seeds and flaxseeds are particularly high in alpha-linolenic acid (ALA), an essential omega-3 fatty acid your body can partially convert into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
EPA and DHA play important roles in the development and maintenance of the nervous system. These long-chain fatty acids also seem to have beneficial effects on pain, inflammation, depression, and anxiety (18Trusted Source, 19Trusted Source, 20Trusted Source, 21Trusted Source).
Since EPA and DHA are primarily found in fish and seaweed, it might be challenging for vegans to consume enough through their diets. For this reason, it’s important for vegans to eat enough ALA-rich foods, such as chia seeds and flaxseeds.
4. Tofu and other minimally processed meat substitutes
Tofu and tempeh are minimally processed meat substitutes made from soybeans.
Both contain 9–20 grams of protein per 3.5-oz (100-gram) portion. They’re also good sources of iron and calcium (24Trusted Source, 25Trusted Source).
Tofu, created by pressing soybean curds, is a popular replacement for meats. It can be sautéed, grilled, or scrambled. It makes a nice alternative to eggs in dishes such as omelets, frittatas, and quiches.
Tempeh is made from fermented soybeans. Its distinctive flavor makes it a popular replacement for fish, but it can also be used in a variety of other dishes.
Fermentation can help reduce the amount of antinutrients that are naturally found in soybeans, which may increase the amount of nutrients the body can absorb from tempeh.
The fermentation process of tempeh may produce small amounts of vitamin B12, a nutrient that’s mainly found in animal foods and not normally found in soybeans.
However, it remains unclear whether the type of vitamin B12 found in tempeh is active in humans.
The amount of vitamin B12 in tempeh also remains low and can vary from one brand of tempeh to another. Therefore, vegans should not rely on tempeh as their only source of vitamin B12 (26Trusted Source, 27Trusted Source).
Seitan is another popular meat alternative. It provides about 18 grams of protein per 3.5 ounces (100 grams). It is also contains iron, calcium, and phosphorus (28Trusted Source).
However, people with celiac disease or gluten sensitivity should avoid seitan due to its high gluten content.
More heavily processed mock meats, such as “vegan burgers” and “vegan chicken fillets,” usually provide far fewer nutrients and can contain various additives. They should be eaten sparingly.
5. Calcium-fortified plant milks and yogurts
Vegans tend to consume smaller amounts of calcium per day than vegetarians or meat eaters, which may negatively affect their bone health. This seems especially true if calcium intake falls below 525 mg per day (29Trusted Source, 30Trusted Source).
For this reason, vegans should try to include calcium-fortified plant milks and plant yogurts in their daily menu.
Those looking to simultaneously increase their protein intake should opt for milks and yogurts made from soy or hemp. Coconut, almond, rice, and oat milks are lower in protein.
Calcium-fortified plant milks and yogurts are usually also fortified with vitamin D, a nutrient that plays an important role in the absorption of calcium. Some brands also add vitamin B12 to their products.
Therefore, vegans looking to reach their daily intakes of calcium, vitamin D, and vitamin B12 through foods alone should opt for fortified products. To keep added sugars to a minimum, you can choose unsweetened versions.