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HealthRX.com · Printable lab tracker

Vitamin D with NMN or NR: daily intake tally and blood test record

Add up the vitamin D from every product you take, compare it with the MedlinePlus reference amounts, and keep any 25(OH)D or calcium results with their units. Bring the sheet when you ask whether a test is needed at all.

Companion to “Can I Take Vitamin D with NMN or NR (Nicotinamide Mononucleotide / Riboside)?” · healthrx.com/supplements-nad-nmn/with-vitamin-d · Facts checked 2026-10-19

Reference points

  • Recommended daily amount: 600 IU (15 mcg) for adults 19 to 70, and 800 IU (20 mcg) over 70.[1]
  • Safe upper limit for children and adults 9 years and older: 4,000 IU (100 mcg) a day.[1]
  • Vitamin D toxicity almost always comes from too many supplements: too much vitamin D makes the gut absorb too much calcium.[1]
  • In 50 healthy older adults, a single vitamin D3 dose reached a 32% higher peak blood level when taken with a fat-containing meal than with a fat-free one.[2]
  • The Endocrine Society panel suggests against routine 25(OH)D testing in the groups it considered.[3]

Every product that contains vitamin D

Include multivitamins, calcium products and fortified drinks you take daily.

ProductIU (or mcg) per servingServings per dayIU per dayTaken with a meal?

Your total

Total vitamin D per day from all products (IU)
NMN or NR product and amount per day
Medicines that can matterfor example rifampin, phenytoin, carbamazepine or a thiazide diuretic

Blood test results

25(OH)D is reported in ng/mL or nmol/L; write the unit every time.

Date25(OH)D resultUnitCalcium resultWhy it was ordered

What high blood calcium from too much vitamin D can cause

  • Confusion and disorientation.[1]
  • Kidney damage or kidney stones.[1]
  • Nausea, vomiting, constipation, poor appetite, weakness and weight loss.[1]

Questions for your clinician

  1. Do I have a reason to have my 25(OH)D level tested?
  2. Is my total daily vitamin D appropriate for my age, or above it?
  3. Do any of my medicines change how much vitamin D I need or how it affects calcium?
  4. Should I take my vitamin D with my main meal?
Sources for the facts on this sheet
  1. U.S. National Library of Medicine, MedlinePlus. Vitamin D: MedlinePlus Medical Encyclopedia. Accessed 2026-10-19. https://medlineplus.gov/ency/article/002405.htm
  2. Dawson-Hughes B, Harris SS, Lichtenstein AH, et al. Dietary fat increases vitamin D-3 absorption. J Acad Nutr Diet 2015. PMID 25441954. https://pubmed.ncbi.nlm.nih.gov/25441954/
  3. Demay MB, Pittas AG, Bikle DD, et al. Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab 2024. PMID 38828931. https://pubmed.ncbi.nlm.nih.gov/38828931/

This sheet records information for a conversation with your prescriber or pharmacist. It does not replace their instructions or the medication's prescribing information.