Bacterially-synthesized Folate Absorption Across the Large Intestine

Is Bacterially-Synthesized Folate Absorbed Across the Colon of Humans?

The purpose of this study is to determine whether folate produced by bacteria that live in our colon can be absorbed in human colon using a stable isotope method. This study would lead a better understanding of the bioavailability of colonic bacterially-synthesized folate and its quantitative contribution to whole body folate homeostasis.

Inclusion Criteria:

1. 18-65 years;
2. overall healthy

Exclusion Criteria:

1. <18 years or >65 years
2. chronic disease (eg. history of hepatic, gastrointestinal, renal, vascular, haematological or neuropsychiatric disease) or surgery affecting gastrointestinal motility, pH or folate absorption/metabolism
3. regular use of medications affecting gastrointestinal pH, motility or folate absorption/metabolism (eg. antiacids, laxatives, phenytoin, sulfasalzine, phenobarbital, primidone, cimetidine, proton pump inhibitors [such as Nexium] and antibiotics [such as Sulfonamides] or nonsteroidal anti-inflammatory drugs [NSAIDS, such as aspirin/ibuprofen])
4. consumption of >1 drink/day of alcohol on a regular basis or current smoking (last 6 months)
5. planning a pregnancy, pregnant, breast feeding or the use of high-dose estrogen oral contraceptives/hormone replacement therapy
6. known sensitivity to sunscreens containing ultraviolet B filters and/or PABA
7. difficulty with swallowing large pills or providing venous blood samples