Vegan diets are exploding all over the world.
People adopt such diets primarily for 2 reasons: health reasons and environmental reasons.
I won’t get into the science of it all (especially since the biggest and most recent studies ever done show that health benefits are minimal and the impact on the environment of replacing animal calories with grains is far worse).
But I wanted to highlight the 3 primary nutrients all vegans need to supplement with for optimal health.
Vitamin B12 (Cobalamine)
Vitamin B12 is a critical vitamin for humans.
We are not able to produce it ourselves (unlike cows for example, who are able to produce it).
B12 is involved in the metabolism (primary function) of every single cell in the human body.
B12 is critical for proper functioning of the nervous system, as well as the development of red blood cells (which carry oxygen in your blood).
Meat (especially organ meats) are the primary sources of B12 (eggs and milk do contain B12 but in minimal bioavailable quantities).
The only source of plant-based B12 is a relatively rare type of algae, which then needs to be fermented for bacteria on it to produce B12. It is not a practical source of sufficient B12 for humans who do not consume animal products.
The form of B12 in other plant-based products is not “bioavailable”: cannot be absorbed by humans as it has a different chemical structure than the one found in animal products.
As such, Vitamin B12 is the first compound that Vegans (and Vegetarians) need to supplement with.
EPA and DHA
EPA and DHA are commonly referred to as Omega 3 fatty acids.
DHA is the most critical one and is found abundantly in the brain. In fact, it is by far the most highly concentrated fatty acid in the brain, and as such is critical for the healing and development of the human brain (especially in small children).
As you may be aware, the richest source of Omega 3 is: fatty fish.
However people are under the wrong impression that walnuts, flaxseeds, and other plant foods contain Omega 3 - except this is not true.
Some plant-based foods contain something called: ALA.
ALA, when consumed by mammals (cows, sheep, humans, etc) will get converted into EPA and then DHA.
The problem though is that (unlike other mammals), the ability of humans to convert ALA to EPA/DHA is extremely low (due to the low concentration of a critical enzyme).
So men convert 1% to 4% of ALA to DHA, while women convert 8% to 18%, which is very low.
This is why humans need EPA/DHA from animal sources: primarily fatty fish.
Once again, some Omega 3 can be obtained from sea algae, but the concentrations are so low that it isn’t really practical.
As such, Vegans do need to supplement (Vegetarians who consume eggs regularly do not).
(a note on supplementing with Omega 3: it’s extremely difficult to find a good source. Omega 3 oxidises easily, so it has to be “cold produced”, “cold stored”, "never exposed to light”. So good quality Omega 3 supplements tend to be expensive for this reason).
Choline is critical for brain function. It plays an important role in maintaining the integrity of cell membranes: it helps keep the membrane (wall) of your cell strong enough to protect you against damage.
It is also critical in maintaining good liver function: people deficient in choline are at risk of fatty liver disease and other liver disorders.
The best source of Choline is eggs. It is also found in meat (especially organ meats) as well as dairy products.
A lot of plants (especially cruciferous vegetables) do contain Choline. However once again, it is in a “low bioavailability form”.
This means that (unlike other animals), humans are not able to absorb and convert the plant-based choline efficiently for proper use.
This is why Choline is the 3rd compound Vegans need to supplement with.