Peer-Reviewed Clinical Data (USDA & ISSN)

Evidence-Based Vegan Nutrition Reference

Transparent clinical reference guide outlining recommended dietary allowances (RDA), bioavailable whole-food sources, and biochemical absorption kinetics for essential nutrients.

What vitamins and minerals do vegans need to monitor closely?

Vitamin B12 (Cobalamin)

Standard Daily RDA: 2.4 mcg / day (or 2000 mcg / week)

MANDATORY SUPPLEMENT

Top Bioavailable Whole Foods

Fortified nutritional yeast, fortified plant milk, cyanocobalamin supplementation

Biochemical Absorption Kinetics

Intrinsic factor in stomach binds B12; saturates at ~1.5–2.0 mcg per meal; passive diffusion handles ~1% of high doses.

Clinical Function: DNA synthesis, red blood cell formation, neurological myelin sheath maintenance.

Iron (Non-Heme)

Standard Daily RDA: 8 mg (Men), 18 mg (Women)

DIETARY WHOLE FOODS

Top Bioavailable Whole Foods

Lentils (6.6mg/cup), Spinach (6.4mg/cup cooked), Tofu (5.4mg/100g), Pumpkin seeds (2.5mg/2 tbsp)

Biochemical Absorption Kinetics

Pairing with Vitamin C (Ascorbic Acid) reduces ferric iron (Fe3+) to highly soluble ferrous iron (Fe2+), boosting absorption 3–4x.

Clinical Function: Hemoglobin oxygen transport, cellular energy metabolism, mitochondrial function.

Calcium

Standard Daily RDA: 1,000 mg / day

DIETARY WHOLE FOODS

Top Bioavailable Whole Foods

Calcium-set firm tofu (350mg/100g), Fortified plant milk (300mg/cup), Tahini (130mg/2 tbsp), Collard greens (268mg/cup)

Biochemical Absorption Kinetics

Low-oxalate greens (kale, bok choy, broccoli) exhibit ~50% calcium absorption compared to ~30% in dairy milk.

Clinical Function: Bone mineral density, muscular contraction, cardiac rhythm transmission.

Omega-3 (ALA, EPA, DHA)

Standard Daily RDA: 1.6g ALA (Men), 1.1g ALA (Women) + 250mg DHA/EPA

DIETARY PLUS ALGAE

Top Bioavailable Whole Foods

Chia seeds (5g ALA/2 tbsp), Ground flaxseed (4.7g ALA/2 tbsp), Walnuts (2.6g ALA/oz), Algal oil (250mg DHA/EPA)

Biochemical Absorption Kinetics

ALA converts to EPA/DHA at low rates (2–10%); direct algal oil bypasses metabolic conversion bottlenecks.

Clinical Function: Cell membrane fluidity, brain neuroprotection, cardiovascular anti-inflammatory pathways.

Zinc

Standard Daily RDA: 11 mg (Men), 8 mg (Women)

DIETARY WHOLE FOODS

Top Bioavailable Whole Foods

Hemp seeds (3mg/3 tbsp), Pumpkin seeds (2.2mg/2 tbsp), Lentils (2.5mg/cup), Tempeh (1.8mg/100g)

Biochemical Absorption Kinetics

Soaking, sprouting, and fermenting grains and legumes reduces phytic acid, maximizing zinc bioavailability.

Clinical Function: Immune cell activation, protein synthesis, wound healing, testosterone regulation.

Iodine

Standard Daily RDA: 150 mcg / day

SALT OR TARGETED

Top Bioavailable Whole Foods

Iodized salt (1/2 tsp = 150 mcg), Seaweed (Nori/Wakame), Kelp supplementation

Biochemical Absorption Kinetics

Easily met with standardized iodized kitchen salt; avoid erratic excessive kelp mega-dosing.

Clinical Function: Thyroid hormone synthesis (T3/T4), basal metabolic rate regulation.

Protein Database→

Complete USDA laboratory nutrient dataset for 80+ whole plant foods.

Nutrition Calculator→

Calculate total calories, micronutrients, and macros for any recipe.

Protein Sources Guide→

Editorial deep dive on high-density plant proteins.

Frequently Asked Questions

How much Vitamin B12 should a vegan take weekly?
Clinical guidelines recommend either 2,000 to 2,500 mcg of Cyanocobalamin once weekly as a chewable/sublingual supplement, or 50 to 100 mcg taken daily. Because stomach intrinsic factor saturates quickly, smaller daily doses or larger weekly doses ensure full biological absorption.
How can vegans maximize non-heme iron absorption?
Non-heme iron (found in lentils, spinach, pumpkin seeds, and tofu) absorption increases by up to 300–400% when consumed alongside Vitamin C (ascorbic acid from bell peppers, citrus, tomatoes, or broccoli). Avoid drinking black tea or coffee during meals due to polyphenols binding to iron.
What is the best vegan source of long-chain Omega-3 (DHA/EPA)?
While flaxseed, chia seeds, and walnuts provide alpha-linolenic acid (ALA), direct preformed DHA and EPA are most bioavailable from sustainably cultivated Algal Oil, which is the identical primary marine source that fish consume.