Bioavailability Study of Folate in Healthy Subjects

A Double Blind, Randomized, Cross-over, Comparative Bioavailability Study of 3 Different Forms of Folate in Healthy Subjects

The aim of this prospective interventional study is to compare the bioavailability of the 6S-5-methyltetrahydrofolate (5-MTHF) glucosamine salt versus two other forms of 5- MTHF calcium salts by measuring serum 5-MTHF responses after a single ingestion of equivalent doses of the three folate forms in humans.

The hypothesis of this study is that the test products 5-MTHF glucosamine and calcium salts have equivalent bioavailabilities in serum 5-MTHF as measured by the area under the curve over a period of 24 hours (AUC0-24h) after consumption of a single dose of 5-MTHF (400μg).

Participants will receive a single dose of each of the following products separated by a 7-day wash-out period:

• 5-MTHF glucosamine salt
• 5-MTHF calcium salt 1
• 5-MTHF calcium salt 2

Inclusion Criteria:

• Body Mass Index (BMI) ≥18 and ≤25Kg/m²,
• For women: menopausal without hormone replacement therapy (HRT) or with HRT started from more than 3 months or non-menopausal with a negative blood pregnancy test and using reliable contraception since at least 3 cycles before the beginning of the study and agreeing to keep it during the entire duration of the study,
• Good general and mental health within the opinion of the investigator: no clinically significant and relevant abnormalities of medical history or physical examination,
• Able and willing to participate to the study by complying with the protocol procedures as evidenced by his/her dated and signed informed consent form,
• Affiliated with a social security scheme,
• Agree to be registered on the subjects in biomedical research file.

After V1 biological analysis the subjects will be eligible to the study on the following criteria:

- Adequate folate status (serum folate between 10 and 45nmol/L, erythrocyte (RBC) folate between 405 and 952 nmol/L),

Exclusion Criteria:

• Suffering from a metabolic disorder,
• Suffering from a severe chronic disease found to be inconsistent with the conduct of the study by the investigator,
• Suffering from diseases that could potentially interfere with folate absorption or metabolism,
• With a known or suspected food allergy or intolerance or hypersensitivity to any of the study products' ingredient,
• With a low venous capital of blood samples according to the investigator's opinion,
• Pregnant or was pregnant less than 6 months prior to the study, or lactating women or intending to become pregnant within 3 months ahead,
• Under treatment or regular use of treatment or dietary supplement which could significantly affect folate status or other study parameter(s),
• Use of supplements containing folate (i.e. folic acid, 5-MTHF) the last 3 months,
• With significant change in lifestyle, food habits, physical activity or medications in the 3 months before the V1 visit or not agreeing to keep them unchanged throughout the study,
• With a current or planned in the next 3 months' specific diet (hyper or hypocaloric, vegan, vegetarian…) or stopped less than 3 months before the study,
• With a personal history of anorexia nervosa, bulimia or significant eating disorders according to the investigator,
• Consuming more than 2 standard drinks of alcoholic beverage daily for men and women or not agreeing to keep his alcohol consumption habits unchanged throughout the study.
• Smoking,
• Having a lifestyle deemed incompatible with the study according to the investigator including high level physical activity,
• Taking part in another clinical trial or being in the exclusion period of a previous clinical trial,
• Having received, during the last 12 months, indemnities for clinical trial higher or equal to 4500 Euros,
• Under legal protection (guardianship, wardship) or deprived from his rights following administrative or judicial decision,
• Presenting a psychological or linguistic incapability to sign the informed consent,
• Impossible to contact in case of emergency.
• Who made a blood donation in the 3 months before the V0 visit or intending to make it within 3 months ahead.

After V1 biological analysis the subjects will be non-eligible to the study on the following criteria:

• Presence of anemia (hemoglobin<12g/dL in women and 13g/dL in men),
• Vitamin B12 levels (serum cobalamin <148pmol/L),
• Serum total homocysteine levels≥15µmol/L,
• Serum creatinine >0,96mg/dL for women and >1,21mg/dL for men,
• Control record (Glycaemia, total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, GGT, ASAT, ALAT, Urea and CBC) with clinically significant abnormality according to the investigator.