Clinical trial NCT05614960: Dried Purple Laver (Nori) as a Food Source of Vitamin B12 in Vegetarians
Official title: The Bioavailability of Vitamin B12 From Nori in Vegetarians: a Dose Response Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Vitamin B 12 Deficiency
Keywords: Vitamin B12
Vegetarian diet
Purple laver (Porphyra sp.)
Nori
Lead sponsor: Fu Jen Catholic University
Sponsor class: OTHER
First posted: 2022-11-14
Enrollment: 30
Sex: ALL
Minimum age (years): 20
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: This is an intervention study aiming to understand the bioavailability of vitamin B12 from nori for vegetarians.

Detailed description: Thirty vegetarian participants will be randomly assigned to one of three intervention arms: (1) 5g of nori (4 sheets, containing 2.4μg vitamin B12), (2) 8g nori (7 sheets, containing 4μg vitamin B12), (3) control group (no nori). At baseline and end of 4 weeks, participants will be measured on serum vitamin B12, methylmalonic acid, holotranscobalamin, homocysteine and folate.

Eligibility criteria: Inclusion Criteria:

* Vegetarians (including vegan, ovo-vegetarian, lacto-vegetarian, lacto-ovo vegetarian)
* Duration of the vegetarian diet: at least 1 year
* Aged 20-60 years old
* Have not taken vitamin B12 or folate supplement within 1 year
* Willing to adhere to study intervention and be tested for vitamin B12 related biomarkers.
* Familiar with LINE application on smartphone

Exclusion Criteria:

* Any disease or surgery that affects the vitamin B12 status (Pernicious anemia, Gastrointestinal disease and surgery, Pancreatic diseases, Chronic kidney disease)
* Hyperthyroidism
* Previous adverse reaction to nori
* Have taken antacid or metformin in the past 1 week
* Alcoholic and not willing to abstinence from alcoholic beverages

Primary outcomes:
measure: Change in holotranscobalamin in 4 weeks
timeFrame: 4 weeks (Week 4 - Baseline)
measure: Change in methylmalonic acid in 4 weeks
timeFrame: 4 weeks (Week 4 - Baseline)
Secondary outcomes:
measure: Change in serum vitamin B12 concentration in 4 weeks
timeFrame: 4 weeks (Week 4 - Baseline)
measure: Change in homocysteine in 4 weeks
timeFrame: 4 weeks (Week 4 - Baseline)
Other outcomes:
Locations:
city: New Taipei City
country: Taiwan
facility: Department of Nutritional Science, Fu-Jen Catholic University
Study officials:
affiliation: Fu-Jen Catholic University, Department of Nutritional Science
name: Tina Hsueh-Ting Chiu, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Chiu THT, Kao YC, Wang LY, Chang HR, Lin CL. A Dietitian-Led Vegan Program May Improve GlycA, and Other Novel and Traditional Cardiometabolic Risk Factors in Patients With Dyslipidemia: A Pilot Study. Front Nutr. 2022 Mar 24;9:807810. doi: 10.3389/fnut.2022.807810. eCollection 2022.
citation: Takenaka S, Sugiyama S, Ebara S, Miyamoto E, Abe K, Tamura Y, Watanabe F, Tsuyama S, Nakano Y. Feeding dried purple laver (nori) to vitamin B12-deficient rats significantly improves vitamin B12 status. Br J Nutr. 2001 Jun;85(6):699-703. doi: 10.1079/bjn2001352.
citation: Suzuki H. Serum vitamin B12 levels in young vegans who eat brown rice. J Nutr Sci Vitaminol (Tokyo). 1995 Dec;41(6):587-94. doi: 10.3177/jnsv.41.587.
citation: Schwarz J, Dschietzig T, Schwarz J, Dura A, Nelle E, Watanabe F, Wintgens KF, Reich M, Armbruster FP. The influence of a whole food vegan diet with Nori algae and wild mushrooms on selected blood parameters. Clin Lab. 2014;60(12):2039-50. doi: 10.7754/clin.lab.2014.140527.
citation: Rauma AL, Torronen R, Hanninen O, Mykkanen H. Vitamin B-12 status of long-term adherents of a strict uncooked vegan diet ("living food diet") is compromised. J Nutr. 1995 Oct;125(10):2511-5. doi: 10.1093/jn/125.10.2511.
citation: Watanabe F, Yabuta Y, Bito T, Teng F. Vitamin B(1)(2)-containing plant food sources for vegetarians. Nutrients. 2014 May 5;6(5):1861-73. doi: 10.3390/nu6051861.
citation: Rizzo G, Lagana AS, Rapisarda AM, La Ferrera GM, Buscema M, Rossetti P, Nigro A, Muscia V, Valenti G, Sapia F, Sarpietro G, Zigarelli M, Vitale SG. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation. Nutrients. 2016 Nov 29;8(12):767. doi: 10.3390/nu8120767.