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Dr. Garrett Smith and the Love Your Liver Network

Hello, hello, hello! Dr. Garrett Smith, also known as The Nutrition Detective (around these here YouTube parts)^[1], has a background that includes a physiology degree, a nutrition minor, strength and conditioning work, and a doctorate in naturopathic medicine.^[2]

In his YouTube biography, he declares himself as the "foremost expert" on vitamin A toxicity and cholestasis.^[3] His X biography describes him as a "World Expert" in vitamin A toxicity and detoxification.^[4]

In a November 3, 2018 post, Smith credited his friend Matt Stone with introducing him to Grant Genereux's work, first through a Facebook post and then a blog article. Smith and Stone wrote Solving the Paleo Equation: Stress, Nutrition, Exercise, Sleep together. Grant's work helped shape Smith's subsequent focus on vitamin A.^[5]

Smith's later teaching also addresses nickel, copper, manganese, liver function, and bile flow.^[6][7][8] His current food list, livestream discussions, and Love Your Liver Network teaching are the main references for this guide's food framework.

He developed what he first called Toxic Bile Theory and later called the Toxic Bile Paradigm.^[9] This is his framework connecting vitamin A and other exposures with liver function, bile flow, and the recirculation or elimination of substances carried in bile. Love Your Liver livestreams 53 and 71 explain the foundations of his interpretation.^[7][8]

The Love Your Liver Network brings his educational work into a course and private community, with discussions, ongoing updates, and member Q&A.^[10] He also hosts weekly public Love Your Liver livestreams covering topics, questions, and participant experiences.^[11] For ongoing Nutrition Detective news and updates, sign up for the Nutrition Detective newsletter.

Kelsey Kenney works with Smith on research, education, and consultations.^{[12][13][14][15]} Her official biography lists a degree in cellular and molecular biology and biotechnology experience.^[12] Smith credits her with prompting him to reconsider flush niacin and with bringing PEA (palmitoylethanolamide) to his attention after her nickel research.^[13][14] In a July 29, 2026 mea culpa (admission of error), he acknowledged that he had been wrong about niacin and explained how Kelsey's input led him to revise his advice.^[13] She is also his girlfriend.^[16]

PEA is a fat-like compound the body makes naturally. In laboratory studies, it can influence endocannabinoid signaling indirectly^[27] and activates PPAR-alpha, a receptor involved in controlling inflammation.^[28]

Small human trials have reported relief of nerve pain associated with diabetes^[29] and of knee pain and stiffness associated with osteoarthritis.^[30] Results vary by condition and formulation, and larger independent studies are still needed.

For more about Kelsey's background and personal health journey, see her December 2024 King Hero's Journey interview with Beth Martens.

Nutrition Detective offers testing and private consultations. Current bookings list consultations with Kelsey and optional Office Hours follow-up by monthly subscription during the six months after a consultation. The official booking page gives current availability and terms.^[15]

Arizona's public register lists Smith's Naturopathic Medical Doctor (NMD) license, 05-893, as issued on October 15, 2005 and active when checked on September 8, 2026.^[17] His published biography says he began his medical practice in 2006.^[18]

1. [1] Smith's video introduction, livestream 268 at 0:04
2. [2] Smith's official biography
3. [3] Smith's YouTube biography
4. [4] Smith's X biography
5. [5] Smith's November 2018 account
6. [6] Nickel, copper, manganese, and food-list discussion, livestream 251
7. [7] Toxic Bile & Cholestasis Basics Review, livestream 53
8. [8] Toxic Bile Theory Explained, livestream 71
9. [9] Smith on the change from Toxic Bile Theory to Toxic Bile Paradigm
10. [10] Love Your Liver Network: course and community
11. [11] Nutrition Detective podcast and weekly livestreams
12. [12] Kelsey Kenney's official biography
13. [13] Smith credits Kelsey on flush niacin
14. [14] Smith credits Kelsey on PEA, livestream 264 at 1:29:28
15. [15] Private consultations and Office Hours
16. [16] Smith describes their relationship, livestream 249 at 19:54
17. [17] Arizona license register (search Garrett Smith)
18. [18] His published 2024 interview biography
19. [27] PEA and endocannabinoid-related signaling: laboratory study
20. [28] PEA and PPAR-alpha: inflammation mechanism study
21. [29] PEA for diabetic nerve pain: randomized trial
22. [30] PEA for knee osteoarthritis: randomized trial

What started Grant Genereux's investigation into whether vitamin A is a toxin?

Grant Genereux, a retired engineer and geologist in Western Canada, says persistent eczema and severe fatigue led him to investigate diet in 2014.^[19]

In his first book, he describes reviewing eczema food-trigger lists, checking a fortified-milk label, and reading about vitamin A before beginning his own dietary experiment.^[20] He later shared his observations and hypotheses through his blog and free books.^[19][20]

In his books, he reports that eczema cleared, fatigue disappeared, and he lost about 20 pounds during his dietary experiment to reduce vitamin A.^[21][22][23] His first book also describes an early recurrence of eczema before later improvement.^[21] His second book says he no longer had eczema after more than three years.^[24]

In February 2019, he described recovery from previously diagnosed chronic kidney disease and said he was no longer leaking protein in his urine.^[25] In September 2026, he reported an eGFR of 63 and interpreted this as his CKD having reversed.^[26]

His September 17, 2026 update also describes a recent setback with muscle and weight loss, poor sleep, and fingertip inflammation. He reported changes that included reducing red meat, switching to chicken, and later stopping honey. His account and diet have continued to change.^[26]

He also shared a ten-week update from his gerbil-feeding experiment on his YouTube channel in February 2017.^[36]

1. [19] Grant's About page
2. [20] Grant's first book, Chapter 5
3. [21] Grant's first book, eczema account, PDF page 382
4. [22] Grant's first book, fatigue account, PDF page 378
5. [23] Grant's first book, weight account, PDF page 258
6. [24] Grant's second book, Preface, PDF page 12
7. [25] Grant's February 2019 kidney account
8. [26] Grant's September 2026 update and diet changes
9. [36] Grant's ten-week gerbil update, February 12, 2017