Gut microbes can make vitamins as well as use them. Gut and Physiology Syndrome gives that activity an important place in its explanation of nourishment and immunity. The helpful distinction is between a nutrient being produced in the gut and a person receiving enough usable nutrient. Those are connected questions, but they are not identical.[1]
What the GAPS Book Describes
Dr. Natasha Campbell-McBride discusses B vitamins, vitamin K2, amino acids and other active substances produced by gut flora. She connects an altered microbial community with disrupted nutrient supply, placing the gut environment alongside the nutrients coming from food.[1]
That adds another step to the question “What did I eat?” Digestion, absorption, microbial activity and the body’s use of a nutrient all matter in the explanation. The digestion and absorption guide covers the food-processing side.
Production and Availability
A 2019 review cited in the book describes intestinal bacteria as both providers and consumers of B vitamins. It distinguishes dietary and microbial routes and notes uncertainty about how bacterially produced B12 reaches the host. Microbial production is not a guarantee of nutritional sufficiency in an individual.[2]
| Question | Why It Matters |
|---|---|
| Can a microbe produce the nutrient? | This describes a microbial capability. |
| Where is it produced and absorbed? | Location and processing affect availability. |
| How much does the person receive and use? | This is the individual nourishment question. |
| Is a deficiency present? | Food history, symptoms and appropriate assessment need to be considered together. |
Vitamin B12 as an Example
The book uses B12 to illustrate its microbial-supply argument. B12 from food also follows a specific digestive and absorption process, including intrinsic factor and uptake in the distal ileum. Supplement and prescription forms have established uses in deficiency care. Gut production is not a reason to discard prescribed B12.[3]
The point for a GAPS kitchen is to keep nourishment and digestion together. It is not to assume that eating well makes a known deficiency impossible, or that a supplement replaces the food and digestive context.
Iron and the Anemia Discussion
Campbell-McBride connects anemia with the microbial and nutritional environment and strongly emphasizes nourishing animal foods, including liver. This is part of her wider argument about restoring the gut rather than thinking only in isolated nutrients.[1]
Anemia is not one diagnosis with one cause. Iron deficiency, absorption problems and other conditions need to be distinguished. Iron supplementation has a role in appropriate deficiency treatment; the book’s nutritional emphasis should not become an instruction to stop prescribed iron or replace treatment with a universal daily-liver rule.[4]
For the related GAPS food discussion, read nutrient deficiency and immune support. Food choice, amount and preparation still belong within the person’s actual GAPS phase.
Vitamin K2 and Food Examples
The 2020 book discusses K2 in connection with calcium use, bones and soft tissues. It names microbial production and fermented-food examples. An example in a nutrient chapter does not automatically make every named food appropriate for strict GAPS; natto, for instance, is soy-based and should not be added on the strength of that example alone.[1]
Use the GAPS food list for food permissions and the applicable introduction sequence for dairy. Keep the nutrient discussion separate from a blanket instruction to add all fermented foods at once.
What About No-Plant GAPS?
Campbell-McBride describes clinical observations of people following No-Plant GAPS and discusses possible microbial contributions to nourishment. Those observations are part of the book’s account, rather than a guarantee that every person eating only animal foods cannot become deficient.[1]
The question remains practical and individual: what foods are being eaten, what digestion is like and whether a particular deficiency has been identified. A dietary label alone does not answer all three.
Vitamins and Hormones Are Different Parts of the Story
The same source section also discusses hormones and other signaling substances. Gut flora as an endocrine organ covers that topic separately, so a statement about vitamin production does not turn into a claim that microbes make every hormone.
If you are looking for practical help with one of the food groups emphasized in the book, my organ-meat course is a relevant companion. Organ Meats Made Easy is listed in my course catalog.
For the wider picture, return to the GAPS hormones and endocrine-health guide.
References
- Campbell-McBride, N. Gut and Physiology Syndrome (2020), “Production of vitamins and hormones,” B vitamins, K2, anemia, liver and No-Plant observations; nutritional-supplement chapters.
- Yoshii K, Hosomi K, Sawane K, Kunisawa J. Metabolism of Dietary and Microbial Vitamin B Family in the Regulation of Host Immunity. Frontiers in Nutrition. 2019;6:48. Providers/consumers, absorption and B12 discussion; listed in the book’s vitamin-production references.
- NIH Office of Dietary Supplements. Vitamin B12: Health Professional Fact Sheet, absorption and deficiency treatment.
- NIH Office of Dietary Supplements. Iron: Health Professional Fact Sheet, deficiency, causes and supplementation context.
Leave a comment