Pinto bean consumption reduces biomarkers for heart disease risk.
OBJECTIVE
To determine effects of daily intake of 1/2 cup pinto beans, black-eyed peas or carrots (placebo) on risk factors for coronary heart disease (CHD) and diabetes mellitus (DM) in free-living, mildly insulin resistant adults over an 8 week period.


METHODS
Randomized, crossover 3x3 block design. Sixteen participants (7 men, 9 women) received each treatment for eight-weeks with two-week washouts. Fasting blood samples collected at beginning and end of periods were analyzed for total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol, triacylglycerols, high-sensitivity C-reactive protein, insulin, glucose, and hemoglobin A1c.


RESULTS
A significant treatment-by-time effect impacted serum TC (p = 0.026) and LDL (p = 0.033) after eight weeks. Paired t-tests indicated that pinto beans were responsible for this effect (p = 0.003; p = 0.008). Mean change of serum TC for pinto bean, black-eyed pea and placebo were -19 +/- 5, 2.5 +/- 6, and 1 +/- 5 mg/dL, respectively (p = 0.011). Mean change of serum LDL-C for pinto bean, black-eyed pea and placebo were -14 +/- 4, 4 +/- 5, and 1 +/- 4 mg/dL, in that order (p = 0.013). Pinto beans differed significantly from placebo (p = 0.021). No significant differences were seen with other blood concentrations across the 3 treatment periods.


CONCLUSIONS
Pinto bean intake should be encouraged to lower serum TC and LDL-C, thereby reducing risk for CHD.
Winham
Donna M
DM
Department of Nutrition, Arizona State University Polytechnic, Mesa, Arizona 85212, USA. donna.winham@asu.edu
Hutchins
Andrea M
AM
Johnston
Carol S
CS
D000328:Adult; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood*; D003327:Coronary Disease / Q000097:blood*; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D007887:Fabaceae / Q000737:chemistry; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
D015415:Biomarkers; D001786:Blood Glucose; D002097:C-Reactive Protein; D002784:Cholesterol; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D006442:Glycated Hemoglobin; D007328:Insulin; D014280:Triglycerides