Vitamins And Vegan Diets: Do I Need Supplements?

A vegan diet can be a great way to make healthier choices, but it's important to ensure you're getting all the nutrients your body needs. While a well-planned vegan diet can provide all the essential nutrients, there are some vitamins and minerals that vegans may need to supplement. This is because certain nutrients commonly found in animal products, such as meat, fish, dairy, and eggs, are lacking in plant-based diets.

Some of the key vitamins and minerals that vegans may need to supplement include vitamin B12, vitamin D, iron, calcium, vitamin A, protein, and omega-3 fatty acids. These nutrients are important for various bodily functions, including energy levels, immune function, bone health, and nerve cell health.

By including a variety of whole foods in their diet and considering supplements when necessary, vegans can ensure they are getting all the nutrients they need to maintain optimal health.

Vitamin B12

Some plant foods that are touted to be rich in vitamin B12 include unwashed organic produce, mushrooms grown in B12-rich soils, nori, spirulina, chlorella, and nutritional yeast. However, there is no scientific evidence to support the claim that vegans who consume these foods do not need to worry about vitamin B12 deficiency. In fact, several studies show that vegetarians and vegans have a higher risk of vitamin B12 deficiency.

The only scientifically proven way for vegans to reach the recommended levels of vitamin B12 is by consuming B12-fortified foods or taking a vitamin B12 supplement. B12-fortified foods commonly include plant milks, soy products, breakfast cereals, and nutritional yeast. It is important to note that nutritional yeast only contains vitamin B12 when it is fortified, and vitamin B12 is light-sensitive and may degrade if stored in clear plastic bags.

Vitamin D

In addition to dietary sources, vitamin D can be synthesised by the body through exposure to sunlight. Most people can meet their vitamin D requirements by spending 15 minutes in the midday sun without sunscreen and with most of their skin exposed. However, this may not be sufficient for individuals with darker skin, those who live in northern latitudes or colder climates, or those who spend limited time outdoors.

To ensure adequate vitamin D levels, it is recommended that vegans have their blood levels tested. If they are unable to maintain normal blood levels through fortified foods and sun exposure, they should consider taking a daily vitamin D2 or vegan vitamin D3 supplement. While vitamin D2 is adequate for most people, some studies suggest that vitamin D3 is more effective at raising blood levels of the vitamin.

During the spring and summer, people in certain regions, such as the UK, can obtain sufficient vitamin D through skin exposure to sunlight. However, vitamin D supplementation is generally recommended during the autumn and winter months, and year-round for individuals with darker skin and those who have limited sun exposure.

Iron

A common misconception is that vegan diets are lacking in iron. However, vegans are no more likely to develop iron deficiency anaemia than the general population. This is because a well-planned vegan diet typically includes plenty of vitamin C, which improves the absorption of non-heme iron.

There are two types of iron: heme iron, which comes from animal sources, and non-heme iron, which is derived from plants. As heme iron is more easily absorbed by the body, vegans are recommended to aim for 1.8 times the usual recommended daily intake of iron. However, more studies are needed to establish whether such high intakes are necessary.

Good sources of iron for vegans include wholemeal bread and flour, breakfast cereals fortified with iron, dark green leafy vegetables such as watercress, broccoli, and spring greens, and dried fruits like apricots, prunes, and figs. Other iron-rich foods include beans, peas, nuts, seeds, and iron-fortified foods such as cereals, enriched breads, and some plant milks.

It is important to note that certain factors can hinder iron absorption. Tea, coffee, and phytates can reduce iron absorption, so it may be helpful to avoid consuming these around mealtimes. On the other hand, vitamin C enhances iron absorption, so including vitamin C-rich foods in meals can boost iron intake. Using cast-iron cookware can also increase iron content in meals, as a small amount of iron may be transferred to the food during cooking.

Calcium

According to the NHS, the recommended daily intake of calcium for adults is 1000 mg per day, increasing to 1200 mg per day for adults over 50. However, studies suggest that most vegans do not meet these recommended intakes. This may increase the risk of bone fractures, with one study showing that vegans consuming less than 525 mg of calcium per day had an increased risk of fractures. Therefore, it is recommended that vegans aim to meet the suggested daily intake of calcium, ensuring they consume at least 525 mg per day.

Vegan sources of calcium include:

• Green, leafy vegetables such as broccoli, cabbage, kale, bok choy, mustard greens, watercress, and okra. However, spinach is not a good source of calcium, as the body cannot digest all of it.
• Fortified plant-based milk and yoghurt alternatives, such as unsweetened soya, pea, oat, and coconut milk.
• Sesame seeds and tahini.
• Bread, including white and brown bread, which is fortified with calcium by law in the UK.
• Dried fruit, such as raisins, prunes, figs, and dried apricots.
• Calcium-set tofu, which has a higher calcium content if prepared with calcium sulfate rather than nigari (magnesium chloride).
• Fortified ready oat cereal.
• Fortified soya and linseed bread.
• Almonds, dried figs, haricot beans, and okra.

While a well-planned vegan diet can provide sufficient calcium, a supplement may be needed if an individual is not consuming enough calcium-rich foods daily. It is recommended to consult a health professional if there are concerns about calcium intake. Additionally, vitamin D plays a crucial role in calcium absorption, so it is important to ensure adequate vitamin D levels through sunlight exposure, diet, or supplements.

Iodine

The iodine content of a particular plant food depends on the amount of iodine in the soil in which it was grown. Food grown near the ocean tends to be higher in iodine.

The only foods considered to have consistently high iodine levels are iodized salt, seafood, seaweed, and dairy products.

The recommended daily intake of iodine for adults is 140-150 mcg. Pregnant women should aim for 220 mcg per day, while breastfeeding women should increase their daily intake to 290 mcg.

Vegans can ensure they get enough iodine by consuming seaweed several times a week or taking an iodine supplement.

Seaweed is an unusually rich source of iodine for vegans. For example, one and a half to two sheets (4 g) of nori can provide the recommended daily intake. However, regular seaweed consumption is not recommended because it provides variable amounts of iodine, and some types of seaweed, such as kelp, contain too much.

Another option is to use a milk alternative fortified with iodine if your daily consumption is consistently around 500 ml (half a carton).

Vegans are considered at risk of iodine deficiency, and studies report that they have up to 50% lower blood iodine levels than vegetarians.

It is important to avoid too much iodine, as this can lead to thyroid disorders, hypothyroidism, or hyperthyroidism.

The US Department of Health allows individuals to consume up to 1,100 mcg of iodine per day, but this is not recommended for optimal health.

Some foods can slow iodine absorption and counteract its beneficial effects. These include vegan staples like flaxseeds, soy, and raw cruciferous vegetables such as broccoli, cauliflower, and cabbage.

• Dried sea vegetables: Dulse, kelp, nori, and wakame
• Fruits: Strawberries, prunes, and cranberries
• Vegetables: Green beans, corn, and potatoes
• Leafy greens: Spring greens and watercress

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