There are many B vitamins, these may be numbered or used by their name:
Vitamin B1 (thiamin)
Vitamin B2 (riboflavin
Vitamin B3 (niacin or niacinamide)
Vitamin B5 (pantothenic acid)
Vitamin B6 (pyridoxine, pyridoxal, pyridoxamine)
Vitamin B7 (biotin)
Vitamin B9 (folic acid/folate),
Vitamin B12 (various cobalamins).
B vitamins are a group of essential nutrients that have certain characteristics in common. They are involved in metabolism and changing our food (carbohydrates, proteins and fats) into energy as well as having individual functions. For example B6 is important for brain function, mood, immune system, antibodies, red cell production and for the formation of B3. Cobalamins (B12) and folate are also important for healthy blood and producing myelin, the sheath around our nerve fibers, as well as synthesizing and regulating DNA for our cells.
A whole food plant based diet will provide plenty of B vitamins (found in cereals, veges and nuts) with the exception of B12.
Cobalamins are made by bacteria which live in the soil. Back when our soils were of high quality and we ate our veges minimally washed straight from the garden, we were getting plenty of B12 from plant based foods. However due to soil depletion and vigorous spraying and washing, plant foods no longer supply adequate B12 levels. There are claims that various yeast and seaweeds have B12 but testing has found these to be somewhat unreliable sources of B12. If you decided to follow a plant based diet, in today’s modern world, a supplement of B12 is important. B12 is reduced significantly as we age. therefore taking a B12 supplement is advantageous as you get older even for meat eaters.
Tips for getting adequate B12
Consume two servings a day of fortified food providing 1.5-2.5mcg each eg ‘vegemeat’, fortified soymilk, marmite (but not vegemite).
Take a daily supplement of at least 25mcg (25-100mcg is a good range) or take a supplement of 1000mcg 3x a week.