Eight healthy adult subjects will be given a meal of one, two or four cups red raspberries, or two slices white bread with or without 200 mg vitamin C, after an overnight fast and consumption of a low polyphenol diet for two days. Blood samples will be taken at various time points over an eight hour period to measure oxidative stress and antioxidant levels in the blood. Each subject will attend 5 study visits with one week intervals and be given each meal in a random order. It is hypothesized that raspberry consumption at higher doses will greater protect against meal-induced oxidative stress compared to bread controls.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
NONE
Enrollment
8
single serving of one, two or four cups red raspberries
two slices white bread alone or with 200 mg vitamin C supplement
Clinical Nutrition and Risk Factor Modification Centre; St. Michael's Hospital
Toronto, Ontario, Canada
change in antioxidant capacity from baseline (-0.25 h)
plasma antioxidant capacity measured using the 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical cation assay and expressed in Trolox Equivalents (TE)
Time frame: -0.25, 0.25, 0.5, 1, 2, 4 hours post-intake
change in lipid peroxidation from baseline (-0.25 h)
serum thiobarbituric acid reactive substances (TBARS) measured as an indicator of the lipid peroxidation product malondialdehyde (MDA)
Time frame: -0.25, 0.25, 0.5, 1, 2, 4 hours post-intake
change in thiols compared to baseline (-0.25 h)
plasma thiols quantified by 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) assay as an indicator of the level of protection against protein oxidation
Time frame: -025, 0.25, 0.5, 1, 2, 4 hours post-intake
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.