This randomized, double-blind, crossover trial (Phase IV) aims to compare the absorption of a novel permeability-enhanced oral vitamin B12 formulation (Ampli-B) versus standard oral vitamin B12 in 12 healthy adults aged 50 years and older. Each participant receives a single dose of each formulation in randomized sequence, separated by a minimum 10-day washout. The primary outcome is time to peak serum concentration (Tmax) of total and active vitamin B12 (holotranscobalamin). Secondary outcomes include Cmax and AUC parameters.

Inclusion Criteria:

1. Males and females 50 years of age and older

2. BMI between 18 to 29.9 kg/m2

3. Females not of child-bearing potential, defined as those who have undergone a sterilization procedure (e.g. hysterectomy, bilateral oophorectomy, bilateral tubal ligation, complete endometrial ablation) or have been post-menopausal for at least 1 year prior to screening Or,

   Woman of child-bearing potential (WOCBP) must be following appropriate contraceptive methods until the last visit:

   • Sexual abstinence.
   • Oral contraceptive.
   • Trans dermal patches or depot injection of a progestogen drug (starting at least 4 weeks prior to product administration).
   • Intrauterine device (IUD), intrauterine system (IUS), subdermal implant, or vaginal ring (placed at least 4 weeks prior to product administration).
   • Sterilised male partner (with the appropriate post-vasectomy documentation of the absence of sperm in the ejaculate).
   • Contraceptives must be effective before product administration.

4. Agrees not to take any vitamin B12 containing supplements until the completion of the study.

5. Agrees to avoid consuming liver, kidney, organ meats and very high B12 containing shellfish (e.g. clams and crab) 72 hours prior to study visits

6. Agrees to consume the standardized meals for each of the study visits

7. Agrees to avoid alcohol intake 48 hours prior to study visits

8. Agrees to maintain current lifestyle habits (physical activity, medications, supplements, and sleep) as much as possible throughout the study

9. Able to fast for 10 hours prior to study visits

10. Provided voluntary, written, informed consent to participate in the study

Exclusion Criteria:

1. Individuals who are pregnant, breast feeding, or planning to become pregnant during the study
2. Allergy, sensitivity, intolerance, or dietary restriction preventing consumption of investigational products
3. History or current diagnosis of any clinically significant disease that may alter vitamin B12 absorption, accumulation, metabolism or excretion
4. Taking vitamin B12 supplements or a multivitamin supplement containing vitamin B12 within the prior 2 months from study product administration.
5. Current use of prescribed and/or over-the-counter (OTC) medications, supplements, and/or consumption of food/drinks that may impact the absorption of vitamin B12
6. Have a serious illness e.g. mood disorders such as depression, anxiety or bipolar disorder, neurological disorders such as MS, kidney disease, diabetes, liver disease, autoimmune disease, bleeding disorders or heart conditions
7. Have an unstable illness e.g. diabetes and thyroid gland dysfunction
8. Current malignancy (excluding Basal Cell Carcinoma) or chemotherapy or radiotherapy treatment for malignancy within the previous 2 years
9. Gastrointestinal or absorption issues (IBD, IBS, Celiac disease, Crohn's disease, history of GI surgery, Small Intestinal Bacterial Overgrowth)
10. Poor venous access
11. Current use of cannabinoid products (>2 times/week). Occasional users will be required to washout and abstain for the duration of the study period
12. Active smokers, nicotine use or drug (prescription or illegal substances) abuse.
13. Chronic past and/or current alcohol use (>14 alcoholic drinks week)
14. Blood donation 60 days prior to baseline, during the study, or a planned donation within 30 days of the last study visit
15. Participation in other clinical research studies 30 days prior to baseline, as assessed by the PI
16. Any other condition or lifestyle factor, that, in the opinion of the PI, may adversely affect the participant's ability to complete the study or its measures or pose significant risk to the participant