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How do vegetarian live as long or some studies say even more when vitamin b12 is not avaiable in typical vegetarian foods?
Short answer:
most long-living vegetarians are not actually B12-deficient, even though B12 isn’t naturally abundant in plant foods.
Why many vegetarians are not B12 deficient in real life
A. Fortified foods (the biggest reason)
In modern societies, many vegetarians consume B12 from:
- Fortified breakfast cereals
- Fortified plant milks (soy, almond, oat)
- Nutritional yeast (fortified)
- Meat substitutes (often fortified)
Even small daily intakes are enough because:
- Adults need only ~2.4 µg/day
- The liver stores years’ worth of B12
So someone may appear “dietarily vegetarian” but
biochemically sufficient.
Dairy and eggs (for lacto-ovo vegetarians)
Many “vegetarians” are
not vegan.
B12 sources include:
- Milk, yogurt, cheese
- Eggs (less, but still some)
These can provide
enough B12 to prevent deficiency, especially combined with fortified foods.
D. Long body storage of B12
The body stores
2–5 mg of B12, mainly in the liver.
- Daily loss is tiny (~0.1%)
- Deficiency can take 3–10 years to appear
- People who switch to vegetarianism later in life may never reach deficiency
This means:
Some people live long lives without
dietary B12 intake for years — because they’re living off past reserves.
