​What’s missing from a vegan diet? (…aside from the obvious)

Jan 26 2021

​What’s missing from a vegan diet? (…aside from the obvious)

According to an article in  The Independent, this year’s Veganuary campaign is set to be the biggest yet, with up to a third more people having tried a plant-based diet during the pandemic, mainly in a bid to be healthier [1]. Plant-based diets are indeed associated with a myriad of health benefits, such as lower blood pressure, lower cholesterol, better blood sugar and reduced body weight, but one common concern about them, is whether they provide all the vitamins and minerals we need. Here we take a look at four supplements you may need on a vegan diet.

Vitamin B12

Why do we need vitamin B12? Vitamin B12 is needed to keep nerves healthy, maintain normal brain function and support the production of DNA and red blood cells. We only need a small amount, circa 1.5 mcg per day, but because it is mainly found in animal products, vitamin B12 deficiency is one of the most common vegan diet deficiencies. In addition to a vitamin B12 supplement, either as a standalone B12 supplement or as part of a broad-spectrum B-Complex, vitamin B12 can also be sourced from fortified foods, such as breakfast cereal and yeast extracts. When supplementing with vitamin B12, the Vegan Society recommends taking at least 10mcg daily [2].


It may not be an obvious contender, but iodine is crucial for healthy thyroid function. Iodine deficiency can lead to hypothyroidism, which can cause low energy levels, dry skin, tingling in your hands and feet, forgetfulness, depression and weight gain. Seaweed, or kelp, is the best food source of iodine, followed by iodised salt – table salt infused with trace amounts of iodine. Shellfish and crustaceans are also naturally high in iodine. Studies show that vegans have 50% lower blood iodine levels than vegetarians [3], let alone pescatarians.


We have to source alpha-linolenic acid, ALA, from our diet, which is why it’s essential, but EPA and DHA , eicosapentaenoic acid and docosahexaenoic acid, are the omega-3s that get the most press. They are not considered essential because your body can make them from ALA, but they are hugely important for brain health, eye health, depression and inflammation.

Getting enough ALA should maintain adequate EPA and DHA levels, however EPA and DHA are mostly found in oily fish and fish oil. ALA is sourced from plant foods, such as flax seed oil, chia seeds, walnuts and hemp seeds, but the conversion of ALA to EPA may be as low as 5%, and to DHA as low as 2% [4], which explains why vegetarians and vegans have up to 50% lower blood and tissue concentrations of EPA and DHA than meat-eaters [5].


Ok, so you CAN source iron from a vegan diet but there are two types of iron, heme iron and non-heme iron, and heme iron, which is more easily absorbed by the body, is only available in animal products. To avoid iron deficiency you would need to increase your (non-heme) iron intake from vegan foods rich in iron. These include cruciferous vegetables, beans, peas, dried fruits, nuts and seeds, and of course, iron-fortified foods. Or stay topped up with a vegan iron supplement.

Here are a selection of our favourite vegan products:

  1. BetterYou Vegan Health Oral Spray , £14.95
  2. Wiley’s Catch Free Vegan Omega 3 Capsules, £29.99 for 60 capsules
  3. A.Vogel Herbamare, £3.99 for 250gms

[1]Veganuary campaign set for biggest year thanks to Covid-inspired diet overhauls | The Independent

[2] Vitamin B12 | The Vegan Society

[3] Iodine status and thyroid function of Boston-area vegetarians and vegans - PubMed (nih.gov)

[4] Achieving optimal essential fatty acid status in vegetarians: current knowledge and practical implications - PubMed (nih.gov)

[5] Omega-3 polyunsaturated fatty acids and vegetarian diets - PubMed (nih.gov)