Vegan diets may increase heart disease risk

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Despite a gross lack of overall scientific evidence, we are often told from vegan diet experts, that strict vegan plant based diets are the best choice for supporting heart health and preventing cardiovascular disease.

However, current scientific research has found that vegans may actually be at an increased risk of developing cardiovascular disease.

Multiple robust studies have now found that the majority of vegans are deficient in the nutrient Vitamin B12.

The consequence of Vitamin B12 deficiency is a condition known as hyperhomocysteinemia, which is characterized by an abnormally high level of homocysteine in the blood, conventionally described as above 15 µmol/L.

Hyperhomocysteinemia is associated with an increased risk of developing atherosclerosis and cardiovascular disease.

A number of studies on vitamin B12 status and vegetarian/vegan diets concluded:

A study review from 2009 on Vitamin B12 and homocysteine status in vegetarians found that – “Overall, the studies we reviewed showed reduced mean vitamin B-12 status and elevated mean homocysteine concentrations in vegetarians, particularly among vegans.” [1]

Another study of which the majority of the test subjects were vegans concluded that – “Vegetarian subjects presented significantly higher tHcy levels, higher prevalence of hyperhomocysteinemia, and lower serum vitamin B(12) levels than omnivore controls.” [2]

One study from 2003 on Vitamin B12 status and hyperhomocysteinemia in vegetarians concluded that – “Vegan subjects and, to a lesser degree, subjects in the (lacto-vegetarian) and (lacto-ovo-vegetarian) group had metabolic features indicating vitamin B-12 deficiency that led to a substantial increase in total homocysteine concentrations. Vitamin B-12 status should be monitored in vegetarians.

Health aspects of vegetarianism should be considered in the light of possible damaging effects arising from vitamin B-12 deficiency and hyperhomocysteinemia.” [3]


The most serious potential health concern for those following strict vegan plant-based diets is the very likelihood of developing Vitamin B12 deficiency.

The reason why vegans are at an increased risk of developing Vitamin B12 deficiency is because strict plant-food diets don’t provide a reliable dietary source of Vitamin B12.  Animal foods such as meat, dairy and seafood are the main proven reliable dietary sources of Vitamin B12.

One systematic review and meta-analysis concluded that those who choose to omit or restrict animal foods from their diets are destined to become vitamin B12 deficient. [4]

Most vegans are recommended to take synthetic Vitamin B12 supplements(methyl-cobalamin) or to consume fortified foods such as red star nutritional yeast or enriched soy milk for example to prevent deficiency.

I won’t use this post to get into the semantics of having of having to rely on synthetic supplements in order to obtain basic essential nutrients, because any healthy diet should be perfectly capable of providing every nutrient we need to survive including Vitamin B12, which of course as the research is showing strict vegan diets do not.

Strict vegan plant based diets have been proven to be typically low or deficient in many essential nutrients such as Vitamin B12, Vitamin D3, Zinc, Iron, Iodine, pre-formed long-chain Omega-3 fatty acids such as DHA, conditionally essential amino acids such as taurine and carnitine and much more.

Plant-based diets are typically excellent choices for supporting health and reducing the risk of developing many degenerative diseases.  However for any diet to be healthy in the long-term it has to be nutritionally complete and balanced, which vegan diets are not without the use of many supplements.

The likely potential for developing Vitamin B12 deficiency and hyperhomocysteinemia would outweigh any potential health benefits that strict vegan plant-based diets could provide such as lower cholesterol or blood pressure levels.

As such with the current scientific research, we urge caution to those following strict plant-based vegan diets and in particular raw vegan diets, which tend to be even more prone to nutritional deficiencies due to how restrictive they are.


1. Vitamin B-12 and homocysteine status among vegetarians: a global perspective.

2. Effect of vegetarian diet on homocysteine levels.

3. Vitamin B-12 status, particularly holotranscobalamin II and methylmalonic acid concentrations, and hyperhomocysteinemia in vegetarians

4. Plasma total homocysteine status of vegetarians compared with omnivores: a systematic review and meta-analysis.

The information in this article has not been evaluated by the FDA and should not be used to diagnose, cure or treat any disease, implied or otherwise.

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