Vitamin D Intake Calculator
Daily vitamin D IU vs RDA from foods plus supplement.
What it does
Vitamin D concentrates in few foods, so gaps hide easily. Salmon carries 570 IU per 3 oz while milk carries 120 per cup and eggs 44 each, against RDAs of 600 IU to age 70 and 800 past. One salmon dinner can cover the day; bread and pasta cover none.
The tool above sums four lines against the RDA. Enter fish, dairy, other foods, and supplement IU, pick 600 or 800, and it prints total, target, and gap. Defaults total 690 IU against 600: 90 IU over.
NIH tables supply every constant. Its consumer sheet sets the RDA ladder with milk at 120 IU per cup, the professional sheet lists salmon 570, trout 645, eggs 44, and cod liver oil 1,360, and the National Academies IOM report stands behind the RDAs at 40 IU per mcg.
Sunlight writes a parallel ledger. Minimal-sun RDAs assume little skin synthesis, so outdoor workers and summer months run surpluses the page cannot see. Supplements close winter gaps; upper limits near 4,000 IU make megadoses a clinician conversation.
How to use
- Enter fish IU (salmon 570/3 oz).
- Enter dairy IU (milk 120/cup).
- Enter other food and supplement IU.
- Pick the 600 or 800 RDA.
- Read total first, then the gap.
- Discuss sun and limits with a clinician.
Formula
- fish
- IU from fish entries.
- dairy/other/supp
- IU from dairy, other foods, pills.
- RDA
- 600 IU to age 70, 800 past.
RDA and food IU follow NIH ODS consumer and professional sheets with IOM 2011 values behind them.
Worked example
Example: salmon plus milk
Defaults: fish 570, dairy 120, RDA 600.
- Inputs: salmon 570 IU + milk 120 IU, RDA 600 (adult 45).
- Total: 570 + 120 = 690 IU.
- Gap: 690 minus 600 = 90 IU over.
- Mcg check: 690 / 40 = 17.25 mcg.
- Tool shows 690 IU, 600 IU RDA, 90 IU over.
Reference table
| Item | IU | Note |
|---|---|---|
| Age 1-70 RDA | 600 | 15 mcg |
| Age 71+ RDA | 800 | 20 mcg |
| Salmon 3 oz | 570 | Top food |
| Milk 1 cup | 120 | Fortified |
| Egg 1 large | 44 | Small share |
Limits
- Intake math only. Blood levels need labs.
- Sun synthesis excluded from totals.
- Food IU are averages; brands differ.
- Upper limits need a clinician.
Common mistakes
- Counting unfortified foods as sources.
- Skipping the supplement line.
- Using mcg and IU interchangeably.
- Ignoring winter sun loss.
- Megadosing past upper limits.
Try it yourself
Quick checks. Answers sit tucked under each question.
Milk 120, egg 44, RDA 800?
Total 0 + 120 + 44 + 0 = 164. Gap 800 minus 164 = 636 IU short.
Salmon 570, egg 44, RDA 600?
Total 570 + 0 + 44 + 0 = 614. Gap 614 minus 600 = 14 IU over.
Questions
How is the gap figured?
Sum food and supplement IU against the RDA. Here 690 vs 600 leaves 90 IU over.
What is the vitamin D RDA?
Ages 1-70: 600 IU (15 mcg). Age 71+: 800 IU (20 mcg). Infants: 400 IU.
How much D per food?
Salmon 570/3 oz, milk 120/cup, egg 44 each, trout 645, cod liver oil 1,360/Tbsp.
Can I split food groups?
Yes. Enter fish, dairy, other foods, and supplement lines separately.
What about sunlight?
Sunlight makes most D for many people; food fills gaps. Minimal-sun RDAs assume little sun.
Can I overdo supplements?
Yes. Upper limits (4,000 IU) and interactions need a clinician; more is not better.
Sources
- NIH ODS: Vitamin D Consumer Sheet (RDA, milk 120)
- NIH ODS: Vitamin D Professional Sheet (food IU table)
- National Academies: Calcium/D DRIs Summary (RDA values)