When the debate arises about vegans needing or not needing supplements to their diet, it very quickly stops being about the science, the nutritional science, chemistry, or biology. It often instead starts shifting more and more toward lifestyle questions and matters of morality and even philosophy. As you can guess, from a scientific standpoint, this is never a good thing. And it is not a good thing when this matter is in question either. It is important to approach this matter from a purely scientific standpoint. So let's do it! Before we start getting into the various supplements that vegans should or should not use, we also need to add a piece of information that is crucial to this matter. It's about the nutritional value of the modern foods that are significantly lower than those from pre-industrial times--before soil contamination, air pollution, and pesticides. Because of this, the need for supplements has increased, not only in the vegan community, but in general.
1. Vitamin B12
The debate on whether vegans need to use B12 supplements is one of the oldest in the vegan community and also one of the most controversial. Once again, the controversy mostly arises from the fact that the debate stops being scientific. When we are looking solely from scientific standpoint, the fact is that the vegan diet, in the vast majority of cases, does not include sources of B12 that provide sufficient levels of this vitamin which is crucial for a number of processes in the human body. Moreover, the ability of the human body to absorb Vitamin B12 from foods diminishes with age and most medical authorities say that even omnivores should start taking B12 supplements once they reach the age of 50.
2. Vitamin D
Vitamin D can be found in a number of foods, unfortunately most of which are not suitable for vegan consumption. But it can also be gained through exposure to direct sunlight. In the vegan community, the opinion often prevails that Vitamin D which is gained from sunlight is enough. In reality, unless you live in particularly sunny regions in the world, the chances are that you will not get enough of it. On top of that, we need to factor in the negative effects of too much exposure to direct sunlight. The good news is that there are a number of vegan-friendly Vitamin D supplements that are obtained from plant life that you can use to supplement your vegan diet.
For omnivores, the majority of their iodine intake comes from (not seafood as you might think), but actually from dairy products. The reason why this is the case, is that farm equipment and cows are cleaned using products that contain iodine. Of course, folks who eat fish get their share from seafood as well. With vegan diet, iodine can be obtained from sea vegetables. Unfortunately, these vary in iodine content and this might just not be enough. The two options for vegans who want to make sure they get enough iodine, are iodized salt and iodine supplements.
DHA is one of the omega-3 fatty acids that have been debated about in the vegan community since they were described. DHA is not present in vegan foods although it can be synthesized from ALA, an amino acid that is present in vegan foods. There is still no conclusive proof that DHA supplementation is beneficial but the truth is that many vegans want to ensure they suffer no negative effects of DHA-deficiency and they already take DHA supplements. Pregnant vegan women should be especially aware and interested in the whole DHA debate because DHA has been found to play role in the creation of milk.
5. Iron and Calcium
The reason why we are lumping these two together, is that they are basic elements and also the fact that calcium supplementation is recommended for vegans and non-vegans alike, especially if they do not eat enough foods that contain calcium. Calcium is considered to be among the nutrients that most people do not get enough of in their food. Iron is mostly recommended to women who have heavy menstruation and once again, it is recommended regardless of one's diet.
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