Complete Vegan Supplement Guide: What You Actually Need

Evidence Guide · Updated 2025

The Complete Vegan Supplement Guide: What You Actually Need

A well-planned vegan diet provides most nutrients, but several have no reliable plant-based sources or have significantly lower bioavailability from plants. This guide covers the evidence-based essentials.

Non-Negotiable (Deficiency Risk Without Supplementing)

Vitamin B12 — The only supplement all vegans must take, without exception. B12 is not reliably present in plant foods. Deficiency causes irreversible neurological damage over time. Dose: 250–500mcg methylcobalamin daily or 2500mcg weekly. Seaweed, nutritional yeast, and fermented foods are not reliable B12 sources.

Omega-3 DHA and EPA — ALA (from flaxseed, chia, walnuts) converts to DHA/EPA in the body at only 5–15% efficiency. Most vegans have DHA blood levels 50–70% lower than omnivores. Use algae-derived omega-3 (the same source fish get their DHA from). Dose: 250–500mg DHA+EPA/day from algae oil. Algae omega-3 is identical in bioavailability to fish-derived omega-3.

Vitamin D3 — D3 from animal sources (specifically lanolin from sheep’s wool) has superior bioavailability vs D2. Vegan D3 is now available from lichen (Vitashine is the main brand). D2 (ergocalciferol, from yeast/mushrooms) works but is less potent and has shorter half-life. Use vegan D3 from lichen, not D2. Dose: 2,000–4,000 IU daily.

Likely Needed (Absorption Differences From Plant Sources)

Iron — Heme iron (animal) absorbs at 15–35%; non-heme iron (plants) at 2–20%. Phytates in grains and legumes further reduce absorption. Vitamin C taken with iron-rich meals doubles non-heme iron absorption. Women of reproductive age are at highest risk. Get tested (ferritin, TIBC) before supplementing — iron excess is harmful.

Zinc — Phytates in plant foods bind zinc and reduce absorption by 30–50% vs animal sources. Vegans have measurably lower zinc status. Zinc picolinate or bisglycinate bypasses some of the absorption limitation. Dose: 15–25mg/day with a meal (not breakfast with high-phytate cereals).

Calcium — Low-oxalate dark leafy greens (kale, bok choy, broccoli) have excellent calcium bioavailability (~50% vs ~30% from dairy). Calcium supplements only if dietary calcium is genuinely low — don’t supplement without assessing intake first. Calcium citrate is better absorbed than carbonate.

Check Status (Not Automatically Deficient)

Iodine — No reliable plant source except seaweed (variable content). Use iodized salt or kelp tablets carefully (seaweed iodine is highly variable — can easily exceed safe upper limit). 150mcg/day from iodized salt or a multivitamin with iodine is safest.

Vitamin K2 (MK-7) — Found in natto (fermented soy) but otherwise mainly animal products. If you don’t eat natto daily, a K2 supplement (100–200mcg MK-7) is warranted, especially with high-dose D3.

Creatine — Only found in animal muscle tissue. Vegans have 20–30% lower muscle creatine stores. Supplementation shows larger relative benefits in vegans than omnivores. Creatine monohydrate 3–5g/day is fully plant-compatible and vegan-certified.

Related Articles

Best B12 Supplement: Forms, Doses, and Who Actually Needs It Evidence Guide · Updated 2025 Best B12 Supplement: Who Needs It and Which Form to Buy Vitamin B12 deficiency is more common than most people realize — particularly in vegans, vegetarians, older adults, and anyone taking metformin long-term. The supplement market offers multiple forms, and the differences matter more than most brands admit. Who Actually Needs B12 Supplementation? B12 is found almost exclusively in animal products. Groups at high risk of deficiency: vegans and vegetarians (no dietary intake), people over 50 (stomach acid production declines, reducing B12 absorption from food), metformin users (metformin reduces B12 absorption in the ileum by…

Best Supplements for Women (2025): Evidence-Based Rankings The best supplements for women ranked by clinical evidence: magnesium for PMS, omega-3 for hormones, collagen for skin, vitamin D3+K2 for bone density. Evidence-based, not marketing.

Best Supplements for Stress and Anxiety (2025):… The best supplements for stress and anxiety ranked by clinical evidence: ashwagandha, magnesium, L-theanine, and what actually works vs the overclaimed herbs.

Best Probiotic Supplements: Strains That Actually… Evidence Guide · Updated 2025 Best Probiotic Supplements: Strains That Have Real Evidence The probiotic supplement market is built largely on marketing. The key insight: probiotics are strain-specific. A study on Lactobacillus rhamnosus GG tells you nothing about whether generic "Lactobacillus rhamnosus" in a cheap supplement works. You need to know the specific strain, not just the genus and species. The Strain-Specificity Problem Most commercial probiotic supplements list genus + species (e.g., L. acidophilus) without the strain code. Clinical research is done on specific strains — the same species from a different manufacturer may behave completely differently. This is why…