Choline Intake: NIH Adequate Intake (425-550mg) and 3,500mg Upper Limit
Educational summary — not medical advice. Talk to your doctor before taking choline above the amount in food and a standard multivitamin. This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
The honest answer
The NIH Adequate Intake (AI) is 425mg/day for adult women and 550mg/day for adult men. Choline has an AI, not a full RDA, because the evidence base wasn't considered sufficient to set one. The Upper Limit is 3500mg/day, based on hypotension and fishy-body-odor thresholds.
The reference numbers
Choline doesn't have one settled number the way some nutrients seem to — it has an Adequate Intake (a government-set minimum-adequacy floor, used because the evidence base wasn't robust enough for a full Recommended Dietary Allowance), deficiency-repletion research amounts, and a separate Upper Limit. The AI is 425mg/day for adult women and 550mg/day for adult men (NIH Office of Dietary Supplements). Actual average US intake falls short of all of these: roughly 402mg/day for men and 278mg/day for women, with only 10.8% of Americans meeting the AI overall (Wallace & Fulgoni 2016). Separately, the controlled human depletion trials that proved a deficiency syndrome exists (Fischer 2007, da Costa 2004) used experimental diets around ~50mg/day to deliberately induce deficiency, then repleted — that figure is a research tool to prove a requirement exists, not a "how much to supplement" target for someone already eating a normal diet.
| Reference point | Amount | What it means |
|---|---|---|
| Adequate Intake, women | 425mg/day | NIH ODS minimum-adequacy standard, adult women |
| Adequate Intake, men | 550mg/day | NIH ODS minimum-adequacy standard, adult men |
| Deficiency-repletion research dose | ~50mg/day (very-low) | Used to deliberately induce deficiency in controlled trials — not a target |
| Upper Limit (UL) | 3500mg/day | Hypotension & fishy-body-odor threshold, adults |
The label-literacy problem: bitartrate mg is not choline mg
Most retail choline is choline bitartrate, a salt. Only about 41.1% of a bitartrate serving's weight is elemental (actual) choline — the ratio of choline's molecular weight (104.17) to choline bitartrate's molecular weight (253.25). Worked example: 1,000mg of choline bitartrate delivers roughly 410mg of elemental choline, not 1,000mg. This is chemistry, not a study finding, and it applies to every bitartrate product regardless of brand. Some labels disclose the elemental figure directly, some disclose both the salt weight and the elemental figure, and phosphatidylcholine products often disclose neither — see best choline for how the four tracked products compare on this exact point.
Dose checker: how much elemental choline are you actually taking?
Enter the choline bitartrate milligrams per serving from your label (look for "Choline Bitartrate ___ mg" on the Supplement Facts panel) and how many servings you take per day. If your label already states elemental choline directly (like Solgar's), enter that number and use a 100% conversion by treating it as elemental.
How to think about it
- Convert bitartrate mg to elemental mg before comparing to the AI or UL. The number on the front of most bottles is the salt weight, not the dose that matters.
- Don't treat the ~50mg/day deficiency-research dose as a target. It was used to deliberately induce deficiency in controlled trials, the opposite of a healthy intake goal.
- The 3500mg Upper Limit is based on hypotension and fishy-body-odor thresholds, not long-term chronic-use safety data — treat it as a ceiling, not a target.
Product pick
Full ranking by disclosed elemental choline mg is on best choline.
Discloses 260 mg elemental choline per serving from 650mg choline bitartrate.
As an Amazon Associate we earn from qualifying purchases. Of 4 products tracked; ranked by disclosed elemental mg, never commissions.
Frequently asked questions
What is the NIH Adequate Intake for choline?
The NIH Adequate Intake is 425mg (women) and 550mg (men). Most Americans fall short of these.
What is the Upper Limit, and what happens above it?
3500mg/day — based on hypotension and fishy-body-odor thresholds seen in trials, not long-term safety data.
How do I convert bitartrate mg to elemental choline mg?
Multiply by ~0.411 — so 1,000mg bitartrate ≈ 410mg elemental choline. Use the calculator above.
Related
- Choline: why 90% of Americans fall short
- Best choline — ranked by disclosed elemental mg, then cost per 100mg
- Do you actually need a choline supplement?
Sources
- NIH Office of Dietary Supplements. "Choline: Fact Sheet for Health Professionals" (AI, UL, average intake, molecular-weight conversion). ods.od.nih.gov/factsheets/Choline-HealthProfessional
- Wallace TC, Fulgoni VL. "Usual Choline Intakes Are Associated with Egg and Protein Food Consumption in the United States." J Am Coll Nutr. 2016. PMID: 26886842
- Fischer LM, et al. "Sex and menopausal status influence human dietary requirements for the nutrient choline." Am J Clin Nutr. 2007. PMID: 17490963 (deficiency-repletion research dose).
- da Costa KA, Badea M, Fischer LM, Zeisel SH. "Elevated serum creatine phosphokinase in choline-deficient humans." Am J Clin Nutr. 2004. PMID: 15213044
- Full product dataset: /choline/cost-by-brand.json (CC BY 4.0).