Vegetarian Vegan Nutrition

Vegetarian & Vegan Nutrition

Vegetarians & Vegans typically eat a wonderfully healthy diet. However their regime on occasion may lead to nutritional deficiencies, a common example being a restriction on what foods they eat can lead to insufficient intake of certain vitamins or minerals.

Strangely on occasion ‘too much of a good thing’ can cause such deficiencies too – read about Iodine levels for example below. In this article we look at common nutritional areas that Vegetarians & Vegans may wish to keep an eye on and how food supplements may assist in good nutritional levels. We give particular focus on the Vitamin B12 and the mineral Iodine.

Many of us at Cytoplan are advocates of healthy dietary regimes such as the ‘Paleo Diet’ and the ‘Mediterranean Diet’ (see previous blog posts for more details on both). And when we say diet we don’t mean dieting for the sake of weight management but what we would perceive – and research would clearly indicate – is eating for good health. And yes several of us follow a vegetarian or vegan regime too.

Having made the decision to follow a very natural and low processed diet rich in healthy fruits, vegetables, nuts, seeds and wholegrains Vegetarians and Vegans frequently have a diet wonderfully rich in vitamins, minerals and a whole host of natural nutrients such as the ‘phyto’ nutrients carotenoids and flavonoids.

It is often thought protein deficiencies are frequently associated with vegetarians and particularly vegans as the common (and main) food sources of protein are meats and dairy – however the reality is that this is not a common occurrence. Excellent vegetarian sources of protein include legumes, grains, nuts, seeds, Soy and Tofu. Strictly speaking nutritionists will recommend that vegetarians and vegans combine several protein sources during the day to ensure a full profile of essential amino acids.

Iodine; Iodine intake and levels are an interesting and important nutritional issue for the whole population and certainly vegetarians and vegans too. There is some excellent information on the Vegan Society website (link to the relevant page below) who comments “Iodine is typically undesirably low in UK vegan diets (about 50 micrograms/day compared to a recommended level of about 150 micrograms per day) unless supplements, iodine rich seaweeds or foods containing such seaweeds are consumed.”

Iodine is important for many functions in the body, dietary intake of iodine is often from processed foods where iodized salt has been added, other sources include beef, fish (particularly cod and mackerel), poultry, dairy products and eggs. Those following dietary restrictions and those with increased needs such as during pregnancy and breastfeeding may well be deficient in Iodine.

Iodine contributes to normal cognitive function, energy-yielding metabolism, normal functioning of the nervous system, the maintenance of normal skin, the normal production of thyroid hormones and normal thyroid function, the normal growth of children.

As Iodine cannot be stored by the body for a long period it must be obtained regularly via the diet. Low Iodine levels lead to problems with the Thyroid gland and sometimes this can be severe. Overall the UK population is considered deficient in Iodine (see link to ICCIDD below), low Iodine in plant foods due to modern agricultural methods is the main culprit as well as poor levels in cow’s milk. As the Vegan Society note seaweed based foods are an excellent source of Iodine and hence ideal for vegetarians and vegans.

As seaweed is unlikely to feature in most diets ‘Kelp’ and seaweed kelp supplements (in tablet or capsule form) are the popular options to boost iodine levels. Kelp is the name given to a whole variety of seaweeds and Kelp contains large amounts of organic iodine. The important note of caution here is that excessive iodine intake may conversely cause either hypothyroidism so when looking to supplement with iodine rich Kelp don’t overdo it; ideally get the right professional advice as to suitable supplementation.

Now onto our ‘too much of a good thing’ comment in relation to Iodine. There are many beneficial nutrients that when taken in high levels can ‘compete’ with other good nutrients to their exclusion. Sometimes high levels of a nutrient can also ‘impair’ the uptake of another beneficial nutrient and on occasion this can happen with Iodine and may be particularly relevant for vegetarians and vegans. There are certain green vegetables that when eaten regularly in large amounts will prevent the body from assimilating iodine and the main two are green cabbages and broccoli.

Please note that good Iodine levels are of particular importance for pregnant or breastfeeding women and the demands for good levels of Iodine will be higher at these times.

A 2003 study* found more than 25% of the lacto-ovo vegetarians and 80% of the vegans participating in the study were iodine deficient compared with only 9% of omnivores with some evidencing severe deficiency. *(Krajčovičová-Kudláčková M. et al. 2003 Iodine Deficiency in Vegetarians and Vegans. Ann Nutr Metab 2003;47:183–185 DOI: 10.1159/000070483)

Vitamin B12; The Main sources of Vitamin B12 are from meat, fish and dairy sources. The vegan Society (link below) notes that “Most vegans know that B12 deficiency can cause neurological complications and tingling sensations or numbness. B12 deficiency is also a common cause of elevated Homocysteine levels in vegans.”

Homocysteine is an amino acid that occurs naturally in the body. Elevated levels of homocysteine have been linked to increased risks of many common disease conditions. Elevated levels of homocysteine are commonly caused when insufficient levels of ‘methyl group’ foods are consumed.

Vegetarians are often deficient in vitamin B12, due to a lack or absence of dietary intake from animal produce leading to elevated homocysteine. There is strong evidence indicating that elevated ‘plasma total homocysteine’ (tHcy) is detrimental to the cardio vascular system and brain, and a contributor to a number of chronic degenerative conditions.

Several studies have confirmed elevated homocysteine levels in those following a vegetarian and vegan diet and these elevated levels are considered to be due to the reduced dietary intake of vitamin B12 from animal products. Vitamin B12 along with the intake of Vitamin B6, folate, choline and betaine are important nutrients required during the methyl group cycle during which the inflammatory radical homocysteine is rapidly converted back into the antioxidant methionine – thus continuing the methyl cycle which is important for a number of processes in the body. A low intake of these nutrients disrupts this cycle and prevents homocysteine from being converted back from a radical to an antioxidant, leaving detrimental elevated circulating Homocysteine levels.

Iron; Red meat is the most bioavailable form of the mineral iron in our diet and unfortunately vegetable sources are poorly absorbed. Irrespective of dietary preferences women during their menstrual years and young girls particularly should consider supporting their diet with iron supplements as their need for iron is greater. Children need recommended iron levels as their demands for nutrients are greater to help manage their growth.

It is a common perception that for vegetarians and vegans iron deficiencies and anaemia are common and due to the absence of meat in the diet. There are however plentiful sources of iron in popular vegetarian and vegan food sources such as pulses and tofu (a useful link to the relevant Vegetarian Society is below).

If you are concerned about your iron levels then seek professional help such as your GP or a qualified nutritional practitioner. Otherwise for vegetarians and vegans we reiterate that menstruating women and young girls should pay particular attention to an excellent iron intake. It is most unusual for men and post menopausal women to need iron supplementation as their demands are much lower. Even for these groups who are also vegetarians and vegans there should rarely be a need for iron supplementation – so again, seek suitable professional advice if you are in these categories and are worried about your iron levels.

Omega 3; Many of us are well educated in Omega 3 and its importance at all stages in life, perhaps none more so than for children. Eating oily fish or taking fish oils are the best form of the long-chain omega-3 fatty acids DHA/EPA which are needed for human health.

Vegetarian and vegan diets should be rich in omega 3 from nuts and seeds. However our body does not convert vegetable sources of omega 3 well and hence vegetarians and vegans require much larger amounts than those people that consume oily fish or take omega 3 supplements made from fish or crustacean sources.

High quality organic cold pressed Flax Oil (made from flaxseeds) is an ideal way for vegetarians and vegans to increase their Omega 3 intake; it can also be added to salads or drizzled over vegetables.

It should also be noted that if you have a diet high in the Omega 6 essential fatty acid this will affect your Omega 3 levels as both Omega 3 and 6 compete for the same convertase enzyme and Omega 6 has priority of uptake.

Vitamin D; Thanks to a great deal of mainstream media reporting and Government efforts many of us are far more educated toward the importance of good Vitamin D levels throughout our lives. Termed the ‘sunshine vitamin’ the main source really is the sun, we require the sun to synthesise the vitamin in our body, so little sun – poor Vitamin D levels.

The main food sources for Vitamin D are oily fish, milk, eggs, beef and liver. High factor sunscreens which are beneficial in protecting our skin unfortunately block the uptake of vitamin D. Vitamin D is now considered one of the most vital vitamins for health and protection and one of the most depleted, particularly in pregnant women, the elderly and those that rarely get outdoors.

Vegetarians and vegans who get plenty of sunshine should have adequate levels of vitamin D – in the periods of sunshine. For dark winter months in the UK (for example) vitamin D levels are likely to be poor and as the main Vitamin D food sources are not suitable for vegetarians and vegans supplementation may be advisable.

B-Complex Vitamins; B Vitamins are water soluble substances that are natural constituents of brewer’s yeast, liver and whole-grain cereals. The water solubility of B complex vitamins means that any excess is excreted and not stored in the body in any appreciable amount – therefore they must be regularly replaced. B-Complex Vitamins are necessary for the normal functioning of the nervous system and may be the single most important factor in the maintenance of the nerves.

We have reviewed Vitamin B12 in detail already. For most of the B-Complex Vitamins the main food sources are either dairy or meat. Therefore for vegetarians and vegans consideration may be given toward a suitable B-Complex supplement:

Vitamin B1 – Main sources are meat and wholegrains, those avoiding meat and wheat may have low intakes.
Vitamin B2 – Main sources meat and dairy.
Vitamin B3 – Main sources meat, fish, poultry, wheat germ and peanuts.
Vitamin B5 – Main sources are offal, egg yolks and wholegrains.
Vitamin B6 – main sources are meat and wholegrains, if grain intake is low then you may be low in the nutrient.

Vegan Society On Iodine
Vegan Society On Vitamin D
Vegetarian Society on Iron
The International Council for the Control of Iodine Deficiency Disorders
Iodine, Pregnancy and Children’s Brain Development

If you have any questions regarding nutritional support for vegetarians and vegans or any other health matters please do contact me (Amanda) by phone or email at any time. I can also put you in touch with a nutritional practitioner in your area.

Amanda Williams
01684 310099

Last updated on 16th December 2014 by


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