Vitamin-Like Compounds: Choline, Carnitine, Inositol, CoQ10 and Other Nutrients That Are Not Vitamins
Choline, carnitine, inositol and CoQ10 are often sold beside vitamins but are not on the list of 13. Here is how the sources classify them and what that does and does not mean.
Content last updated . This page has not been medically reviewed.
Quick answer
Choline, carnitine, inositol and coenzyme Q10 (CoQ10) are not among the 13 vitamins. MedlinePlus lists 13 essential vitamins and then adds that "vitamin-like nutrients" are also needed, naming choline and carnitine. [1] This page is about classification only. Each nutrient's evidence and safety are on its own page.
How the terms are used
- Vitamin. The Merck Manual describes vitamins as organic substances; the ones the body cannot make in sufficient amounts are called essential vitamins and must come from food. [2]
- Conditionally essential. A 2024 review in Advances in Nutrition uses this term for carnitine: most people can make enough to meet their needs, but in some circumstances the body's own production is not enough. [3]
- Vitamin-like. A plain label, used by MedlinePlus for choline and carnitine. [1] It is not a regulatory category in the sources we read.
What the sources say about each
| Nutrient | What the source found | Official intake reference | More |
|---|---|---|---|
| Choline | Listed by MedlinePlus as a vitamin-like nutrient. [1] Health Canada's vitamin reference table (2025 page) includes choline with Adequate Intake (AI) values, not RDAs. [4] | AI, for example 550 mg a day for males and 425 mg for females aged 19 to 50 (Health Canada) [4] | More about Choline → |
| Carnitine | Healthy people can make all they need; classed as conditionally essential. The review says no recommended daily intake has been established. [3] | None established per the 2024 review [3] | More about Carnitine → |
| Inositol (myo-inositol) | Can be formed in the body from glucose, is found in foods including breast milk, and is sold as a supplement. [5] | Proper evidence not found: we did not find an intake reference for it. The Health Canada vitamin table lists none [4] | Not covered elsewhere on this site |
| CoQ10 | Naturally present in the human body, with the highest levels in the heart, liver, kidneys and pancreas; sold as a supplement. [6] | Proper evidence not found in the pages read. The Health Canada vitamin table lists none [4] | More about CoQ10 → |
Whether choline should be called essential, conditionally essential or "vitamin-like" is a classification question where bodies word it differently. This guide follows MedlinePlus's wording and does not rank the terms.
Who may need more than the body makes
The carnitine review says developing newborns, people with selected inherited disorders, people on a strict vegan diet and people on dialysis may need dietary or supplemental carnitine. [3] That is a medical question: a clinician decides, not a label. For the vegan diet more broadly see Supplements in vegetarian and vegan diets.What "conditionally essential" does not mean
- It does not mean everyone needs a supplement; the same review says healthy people make what they need. [3]
- It does not mean a supplement treats a disease. For CoQ10, NCCIH says the overall evidence does not support the idea that it reduces muscle pain caused by statins. [6]
- It does not mean safe at any amount. See below.
Frequently asked questions
Is choline a vitamin?
It is not on the list of 13 vitamins, but MedlinePlus calls it a vitamin-like nutrient. [8][1]
Is CoQ10 a vitamin?
It is not among the 13. NCCIH describes it as a substance naturally present in the body. [1][6]
What does conditionally essential mean?
Most people can make enough, but in some circumstances production falls short. [3]
Do I need a vitamin-like supplement if I take vitamins?
Proper evidence not found for a general need. Ask a clinician or pharmacist; see Do I need a supplement?
Does this page recommend an amount?
No. The only amounts are published reference values for stated groups, with their source. [4]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
How to read the evidence labels
Labels used on this page: established nutritional role, insufficient evidence, Proper evidence not found.
Safety
- NCCIH says CoQ10 may interact with the blood thinner warfarin and the diabetes drug insulin, and may not be compatible with some cancer treatments. [6] Mild side effects such as insomnia or digestive upsets may occur. [6]
- Supplements can interact with medicines and matter before surgery. [7] Read How medication interactions work.
- Many supplements have not been tested in pregnant women, nursing mothers or children. [7]
- If you have kidney disease, are on dialysis or take blood thinners, speak to your clinician or pharmacist first.
- Product quality varies: Quality testing and certifications.
References
- MedlinePlus Medical Encyclopedia, Vitamins. Review date 1/21/2025. Read 2026-10-23.
- Merck Manual Consumer Version, Overview of Vitamins. Full review Jun 2026. Read 2026-10-23.
- Adv Nutr 2024, Carnitine (update of Odle et al. 2014). Read 2026-10-23.
- Health Canada, Dietary reference intakes tables: Reference values for vitamins. Page dated 2025-11-19. Read 2026-10-23.
- MacFarlane PM, Di Fiore JM, Myo-inositol effects on the developing respiratory neural control system. Adv Exp Med Biol 2018. Read 2026-10-23.
- National Center for Complementary and Integrative Health (US), Coenzyme Q10. Read 2026-10-23.
- National Center for Complementary and Integrative Health (US), Using Dietary Supplements Wisely. Read 2026-10-23.
- MedlinePlus (US National Library of Medicine), Vitamins. Read 2026-10-23.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.