After years of trial, error, and way too many pill bottles cluttering my bathroom cabinet, I've learned that vegan supplementation works best when you keep it simple.
When I first went vegan at 35, I panicked about nutrition. My analytical brain, trained by years in finance, wanted to optimize everything.
I bought every supplement the internet recommended and ended up with a cabinet full of bottles I couldn't keep track of. Sound familiar?
Here's what five years of plant-based living has taught me: most vegans don't need a pharmacy's worth of pills. We need a few key nutrients that are genuinely harder to get from plants, taken consistently. The rest? Often unnecessary if you're eating a varied whole-foods diet.
Let me walk you through what actually matters.
1. Vitamin B12: The non-negotiable one
I'll be direct here: every vegan needs to supplement B12. No exceptions, no debates.
This vitamin is produced by bacteria and is found reliably only in animal products or fortified foods. Your body stores it for years, which means deficiency creeps up slowly and can cause serious neurological damage before you notice symptoms.
I take 2,500 mcg of cyanocobalamin weekly, though you can also take a smaller daily dose. The National Institutes of Health recommends adults get 2.4 mcg daily, but absorption varies, so higher supplemental doses ensure you're covered. This one isn't about perfection or optimization. It's about protecting your nervous system.
Have you had your B12 levels checked recently? It's worth asking your doctor to include it in routine bloodwork.
2. Vitamin D: The sunshine vitamin most of us miss
Here's something that surprised me: vitamin D deficiency isn't just a vegan problem. It's an everyone-who-lives-indoors problem. But vegans face an extra hurdle because D3, the more effective form, typically comes from animal sources like lanolin or fish oil.
I started paying attention to this after a particularly dark Portland winter left me exhausted and moody. My levels were in the basement. Now I take 2,000 IU of vegan D3 daily, sourced from lichen. The Harvard T.H. Chan School of Public Health notes that many experts recommend 1,000 to 2,000 IU daily, especially for those with limited sun exposure.
If you work indoors, live in a northern climate, or have darker skin, this one deserves your attention. Consider getting tested to know your baseline.
3. Omega-3s: The brain food worth investing in
For years, I thought my daily flaxseed was handling my omega-3 needs. Then I learned about conversion rates. Your body can convert the ALA in flax, chia, and walnuts into the EPA and DHA your brain actually uses, but the conversion is inefficient. We're talking single-digit percentages.
As someone who runs 25 miles a week and relies on mental clarity for writing, I decided not to gamble on conversion. I take an algae-based omega-3 supplement providing around 250 mg of combined EPA and DHA daily. Algae is where fish get their omega-3s anyway, so we're just cutting out the middlefish.
Do you notice brain fog or struggle with focus? It might be worth examining your omega-3 intake beyond just plant sources.
4. Iodine: The quiet essential
This one flies under the radar, but it matters. Iodine supports thyroid function, which regulates your metabolism, energy, and so much more. If you've ditched dairy and don't eat much seaweed, you might be falling short.
I was skeptical until I learned that plant-based diets can be low in iodine unless you're intentional about it. I use iodized salt in cooking and take a modest supplement providing around 150 mcg a few times a week. The key is not to overdo it, as too much iodine can also disrupt thyroid function.
Sea vegetables like nori and wakame are good food sources, but their iodine content varies wildly. A small, consistent supplement takes the guesswork out of it.
5. Iron: Context-dependent but worth monitoring
I debated including iron because not every vegan needs to supplement it. But enough of us struggle with it, especially menstruating women and endurance athletes, that it deserves a spot on this list.
Plant-based iron is non-heme iron, which your body absorbs less efficiently than the heme iron in meat. Pairing iron-rich foods like lentils, spinach, and fortified cereals with vitamin C dramatically improves absorption. I eat this way intentionally and my levels stay solid without supplementation most of the time.
However, during heavy training cycles or particularly stressful periods, I've needed a low-dose iron supplement. The research suggests that vegetarians and vegans should monitor iron status and consider supplementation based on individual needs rather than blanket recommendations.
Get tested before supplementing iron, as too much can be harmful. Know your numbers.
Final thoughts
When I look back at my early vegan days, I wish someone had told me to slow down and focus on what actually matters. Five supplements. That's it. B12 and vitamin D are essential for nearly everyone. Omega-3s and iodine fill common gaps. Iron depends on your individual situation.
The rest of your nutrition? It can come from food. Beautiful, delicious, whole plant foods that you actually enjoy eating. Supplementation should support your diet, not replace the joy of nourishing yourself well.
What does your current supplement routine look like? Sometimes the most powerful change is simplifying, trusting the process, and paying attention to how your body responds. That's been my path, anyway.
