There’s two ways to tackle this subject, I can either dip in, offer the facts, and then jump out. Or, I can dive in deep, swim around for ages, and probably never surface again ……….. let’s see how long I can hold my breath for.
My main reason for spending time on this subject is selfish, it’s self-education, but if I can prick the ears of a few of you, then all to the good. It’s a fascinating subject, and one that I believe will be touched upon in nearly every conversation that I have with a meat-eater. It seems to be their opening line, my lack of this, and my lack of that. So it’s best I prepare myself with some solid vegan apologetics.
Although a plant-based diet will deliver most vitamins in abundance, vegans (and many non-vegans) do need to pay special attention to their Vitamin B12, Vitamin D, Omega 3 Fatty Acids (DHA & DPA), Iodine, Zinc, Selenium and finally K2 intakes.
What are Vitamins ?
Vitamins are essential to life, but cannot be synthesised by the body in adequate amounts. Therefore, outside sources must be obtained. Although the total amount of vitamins the body needs is tiny – only 0.5 gram per day – the functions they perform are vital. Some, such as vitamin D, have hormone-like functions as regulators of mineral metabolism, or regulators of cell and tissue growth and differentiation (such as some forms of vitamin A). Others can function as antioxidants (e.g., vitamin E and sometimes vitamin C). The largest number of vitamins, the B complex vitamins, function as enzyme cofactors (coenzymes) or the precursors for them; coenzymes help enzymes in their work as catalysts in metabolism. In this role, vitamins may be tightly bound to enzymes as part of prosthetic groups: For example, biotin is part of enzymes involved in making fatty acids. They may also be less tightly bound to enzyme catalysts as coenzymes, detachable molecules that function to carry chemical groups or electrons between molecules. For example, folic acid may carry methyl, formyl, and methylene groups in the cell. Although these roles in assisting enzyme-substrate reactions are vitamins’ best-known function, the other vitamin functions are of equal importance.
Although a plant-based diet will deliver most vitamins in abundance, vegans (and many non-vegans) need to pay special attention to their vitamin B12, and D intake. Let’s take a look at B12.
Vitamin B12 has the largest molecular structure of any vitamin, with the mineral cobalt at it’s centre. It’s a water-soluble vitamin that has a key role in the normal functioning of the brain and nervous system via the synthesis of myelin, and the formation of red blood cells. It is one of eight B vitamins, and is involved in the metabolism of every cell of the human body, especially affecting DNA synthesis, fatty acid and amino acid metabolism.
Vitamin B12 deficiency can offer a range of symptoms such as fatigue, lethargy, depression, poor memory, breathlessness, headaches, and pale skin, among others, especially in elderly people (over age 60) who produce less stomach acid as they age, thereby increasing their probability of a deficiency. Vitamin B12 deficiency can also cause symptoms of mania and psychosis in more severe cases.
The body requires vitamin B12 in tiny amounts; the official Recommended Dietary Allowance (RDA) for adults is 2.4 mcg per day. However, recent reports are suggesting that this be more akin to between 4 to 7 mcg per day. Ingestion options for the current RDA are :
- Consume fortified foods 2-3 times per day to get at least 3 micrograms of vitamin B12
- or take 10 micrograms of B12 as a compliment once per day
- or take 2000 micrograms of B12 as a compliment once per week
Fortified foods include some common breakfast cereals, soy milks, almond milks, coconut milks, other plant milks, nutritional yeast, vegan mayonnaise, tofu, and various types and brands of vegan deli slices, burgers, and other veggie meats.
There’s so much data out there that suggests average vegan intakes of vitamin B12 to be far below the RDA, with numbers suggesting up to a 25 percent shortfall in intake. Vegans who don’t include a reliable source of vitamin B12 will eventually become deficient. This could take months for some, and years for others, but it will happen, with damage ranging from the dramatic, to the irreversible.
I hope you have enjoyed reading this, I’ve certainly enjoyed writing it. Tomorrow we’ll look at Vitamin D, it’s function, and how we can get more of it.