Vegan Diets: Four Key Nutrients Of Concern

A vegan diet is based on plants and foods made from plants. Vegans do not eat foods that come from animals, including dairy products and eggs.

There are four nutrients that are of particular concern in a vegan diet: vitamin B12

Iron

Good sources of non-heme iron for vegans include:

• Wholemeal bread and flour
• Breakfast cereals fortified with iron
• Dark green, leafy vegetables (e.g. watercress, broccoli, kale)
• Dried fruits (e.g. apricots, prunes, figs)
• Legumes (e.g. lentils)
• Tofu
• Soybeans
• Green peas

Consuming foods rich in vitamin C can help improve the absorption of non-heme iron. For example, adding tomatoes, salsa, or red bell pepper to meals containing plant-based iron sources can enhance iron absorption.

It is important to note that while iron deficiency can lead to anaemia and decreased immune function, excessive iron intake can also be harmful. Unnecessary iron supplementation can damage cells, block the absorption of other minerals, and in extreme cases, lead to organ failure or coma. Therefore, it is crucial to monitor iron levels and only supplement when necessary.

Overall, with proper planning and a varied diet, vegans can ensure they are getting sufficient iron to maintain their health.

Vitamin B12

To get sufficient amounts of vitamin B12, people following a vegan diet must take supplements or eat foods that have been fortified with this nutrient. These include:

• Enriched yeast extracts
• Nori seaweed, a type of marine algae
• Tempeh, a fermented soy product
• Fortified nutritional yeast
• Fortified veggie "meats"
• Fortified cereals
• Fortified non-dairy "milk"

The recommended intake of vitamin B12 for vegans is to take a daily supplement providing at least 10 micrograms (mcg) or a weekly supplement of at least 2000 micrograms. Eating fortified foods two or three times a day can also provide at least three micrograms of B12 per day.

It is important to note that not all sources of vitamin B12 are equal. For example, spirulina offers only pseudovitamin B12, which cannot be absorbed by the body. Similarly, while some plant foods like nori seaweed, tempeh, and barley grass have been suggested as suitable non-animal sources of B12, they have not been proven to provide adequate amounts of this vitamin over time.

In summary, vitamin B12 is a crucial nutrient for overall health, and vegans should ensure they are getting enough through supplements or fortified foods to avoid potential health complications.

Calcium

Recommended Daily Intake

The recommended daily calcium intake varies depending on age and gender. For adults aged 19 to 50, the recommended intake is 1000 mg per day. For women over 51 and men over 70, the requirement increases to 1200 mg per day.

Vegan Sources of Calcium

Vegan sources of calcium include:

• Fortified plant-based milk alternatives, such as unsweetened soya, pea, and oat drinks
• Tofu prepared with calcium sulfate
• Green leafy vegetables like broccoli, cabbage, and collard greens, but not spinach due to its poor bioavailability
• Sesame seeds and tahini
• Bread, especially in countries like the UK, where calcium is added to flour by law
• Dried fruits, including raisins, prunes, figs, and dried apricots

It is important to note that the absorption of calcium from plant sources may be lower compared to dairy products. However, consuming foods rich in vitamin C, such as tomatoes or red bell peppers, can enhance the absorption of calcium from plant-based sources.

Vegans who do not consume enough calcium may be at risk of calcium deficiency, which can increase the risk of bone fractures. Therefore, it is crucial for vegans to ensure they are meeting the recommended daily intake of calcium through their diet or consider taking supplements if necessary.

Vitamin D

It's important to note that the body's ability to produce vitamin D from sunlight decreases with age, and using sun protection is recommended to prevent skin damage. As a result, everyone, regardless of their diet, should consider taking a daily supplement during the autumn and winter months when sun exposure is limited.

To ensure adequate vitamin D intake, it is recommended that vegans include fortified foods in their diet and consider taking supplements, especially during periods of reduced sun exposure.

Zinc

An insufficient intake of zinc can lead to developmental problems, hair loss, diarrhoea, and delayed wound healing. The Recommended Dietary Allowance (RDA) for zinc is currently set at 8–11 mg per day for adults, 11–12 mg for pregnant women, and 12–13 mg for lactating women.

To maximise zinc intake, it is important to eat a variety of zinc-rich foods throughout the day. These include whole grains, wheat germ, tofu, sprouted breads, legumes, nuts, and seeds. Soaking nuts, seeds, and legumes overnight, eating enough protein, and consuming fermented foods such as tempeh and miso, can also help boost absorption.

Vegans who are concerned about their zinc intake or those exhibiting symptoms of a deficiency may consider taking a daily zinc gluconate or zinc citrate supplement that provides 50–100% of the RDA.

• Beans (3/4 cup cooked) = 1-2 mg
• Lentils (3/4 cup cooked) = 2 mg
• Oatmeal (1 cup cooked) = 2.3 mg
• Brown rice (1 cup cooked) = 1.9 mg
• Tofu (100 g) = 1.7 mg
• Tempeh (100 g) = 1.7 mg
• Cashews (30 g) = 1.7 mg
• Quinoa (1 cup cooked) = 1.6 mg
• Green peas (1/2 cup) = 1.4 mg
• Pumpkin seeds (1 tbsp) = 1.2 mg
• Brazil nuts (30 g) = 1.2 mg

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