The short version
If someone eats fully plant-based, B12 is the nutrient to plan on purpose. That does not always mean a pill: fortified nutritional yeast, cereals, plant milks, or other fortified foods can count when the label and frequency are reliable. But no reliable B12 source is not a brave whole-foods choice. It is a gap.
- B12: required from reliable fortified foods or a supplement on a fully plant-based diet.
- Vitamin D: conditional on sun exposure, latitude, skin coverage, season, age, and fortified-food intake.
- Iodine: conditional on iodized salt, seaweed habits, dairy/egg intake, pregnancy status, and thyroid context.
- Calcium, omega-3s, iron, zinc, and selenium: usually food-first, sometimes supplement-supported depending on intake and labs.
B12 is still real
The rumor that B12 is 'not true anymore' usually comes from a real change in the food environment: more foods are fortified now. That changes the form, not the requirement. Fortified food is supplementation delivered through food. It can be a great option, but it still needs to be intentional and consistent.
- Check the label. Not every plant milk, meat alternative, cereal, or nutritional yeast contains B12.
- Watch frequency. A once-in-a-while fortified food is not the same as a dependable source.
- Do not use B12 as an energy booster if your B12 status is already adequate; deficiency correction and hype are different things.
- Older adults, people with absorption issues, and some medication users may need individualized guidance regardless of diet style.
The conditional list
Most supplement questions are really routine questions. What do you actually eat? Do you use iodized salt? How much sun reaches your skin? Do your fortified foods include calcium and vitamin D? Are you pregnant, lactating, training hard, restricting calories, or managing a medical condition? The answer changes with the person.
- Vitamin D: few foods naturally contain much of it, so fortified foods, sun exposure, and sometimes supplements matter.
- Iodine: iodized salt is predictable; seaweed can swing from tiny to excessive, and many sea salts are not iodized.
- Calcium: fortified plant milks, calcium-set tofu, greens, beans, and other foods can work, but low-calcium patterns are common.
- Omega-3s: chia, flax, walnuts, canola oil, and soy foods help with ALA; algae DHA/EPA is optional, not universally mandated.
- Iron and zinc: legumes, whole grains, nuts, seeds, and vitamin-C-rich meals help, but needs and absorption vary.
- Selenium: soil matters, and Brazil nuts are powerful enough that 'more' is not automatically smarter.
What not to do
The mistake is treating supplements like a moral category. Taking one does not mean the diet failed. Skipping one does not mean the diet is cleaner. The goal is adequacy, not vibes.
- Do not megadose iodine, selenium, iron, or fat-soluble vitamins without a clinician involved.
- Do not assume 'whole-food plant-based' automatically means nutritionally complete.
- Do not assume a multivitamin fixes a thin, low-calorie, low-variety diet.
- Do not let supplement marketing turn a practical B12 plan into a 12-bottle ritual.
A practical check
Use this as a quiet audit, not a scare list. If the answers are clear, you probably need less supplement noise. If the answers are fuzzy, that is where a label check, a food log, or a clinician-ordered lab can be useful.
- Can you name your reliable B12 source and how often you get it?
- Do you regularly use calcium- and vitamin-D-fortified foods, or another dependable source?
- Is your salt iodized, or do you have another sensible iodine source?
- Do most weeks include legumes, whole grains, nuts or seeds, fruit, and vegetables?
- Are pregnancy, lactation, age, thyroid disease, anemia history, GI issues, or medications changing the equation?