Organic potassium salts or fibers effects on mineral balance and digestive fermentations in rats adapted to an acidogenic diet.
BACKGROUND
Fibers and potassium (K) organic salts in plant foods are liable to affect Ca and Mg balance at digestive and renal levels, respectively. K organic salts could counteract the acidifying effects of western diets and consequences of excess NaCl.


OBJECTIVE
To study this question, male rats were adapted to a basal acidifying low-K (LK) diet, or to diets supplemented with a fiber mix (LK/F), or K citrate (HK) or both (HK/F).


RESULTS
HK and HK/F diets displayed a marked alkalinizing effect in urine and promoted citraturia, but this effect was not modulated by fibers. The effect of fibers on Ca digestive absorption was more potent than K citrate effect on Ca renal excretion. In contrast, K citrate effect on kidney Mg excretion was more effective than that of fibers on Mg digestive absorption, a maximal effect on Mg balance was observed in rats fed the HK/F diet. Digestive fermentations in rats fed the LK/F diet were characterized by high-propionic acid fermentations and succinate accumulation. In rats adapted to the HK/F diet, K citrate supplementation depressed succinate and increased butyrate concentrations.


CONCLUSIONS
Organic anions arising from digestive fermentations seem to be not directly involved in the alkalinizing effects of plant foods. Fibers and organic K salts exert distinct effects on Ca and Mg metabolism, but with interesting interactions as to Mg balance, digestive fermentations and urine pH.
Sabboh
Houda
H
Unité des Maladies Métaboliques et Micronutriments, INRA de Clermont-Ferrand/Theix (CRNH d'Auvergne), 63122, St-Genes-Champanelle, France.
Besson
Catherine
C
Tressol
Jean-Claude
JC
Coudray
Charles
C
Horcajada
Marie-Noëlle
MN
Coxam
Véronique
V
Rémésy
Christian
C
Demigné
Christian
C
D000136:Acid-Base Equilibrium / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000652:urine; D004043:Dietary Fiber / Q000008:administration & dosage* / Q000378:metabolism; D004063:Digestion; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007408:Intestinal Absorption; D008274:Magnesium / Q000378:metabolism / Q000652:urine; D008297:Male; D008903:Minerals / Q000378:metabolism*; D019357:Potassium Citrate / Q000008:administration & dosage; D017680:Potassium Compounds / Q000008:administration & dosage* / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D017673:Sodium Chloride, Dietary / Q000009:adverse effects / Q000378:metabolism; D016482:Urinalysis; D014556:Urine / Q000737:chemistry
D004043:Dietary Fiber; D008903:Minerals; D017680:Potassium Compounds; D017673:Sodium Chloride, Dietary; D019357:Potassium Citrate; D008274:Magnesium; D002118:Calcium