Effects of low-carbohydrate, high-fat diets on apparent digestibility of minerals and trace elements in rats
Related Experiment Video
Updated: Apr 27, 2026
Palatable Western-style Cafeteria Diet as a Reliable Method for Modeling Diet-induced Obesity in Rodents
Published on: November 1, 2019
Lena Frommelt1, Maximilian Bielohuby2, Barbara J M Stoehr2
1Chair of Animal Nutrition and Dietetics, Ludwig-Maximilians University, Munich, Germany.
Objective:
Ketogenic low-carbohydrate, high-fat (LCHF) diets reduce growth and bone mineral density in children with epilepsy and in rats. Part of this effect might be due to a reduced availability of calcium in high-fat diets. The aim of this study was to determine mineral digestibility by total collection method in LCHF diets compared with a chow diet and a standard high-fat diet (HFD, high in fat and carbohydrates).
Methods:
Twelve-wk-old male Wistar rats were pair-fed isoenergetic amounts of either six different LCHF diets based on tallow and casein (crude fat 75%-50%, crude protein 10%-35%), with chow or with a HFD diet. Mineral-to-energy ratio was matched in all diets. Circulating parathyroid hormone was measured by immunoassay.
Results:
The apparent digestibility of calcium was reduced in all HFDs (high-fat diets, LCHF diets and the HFD diet) by at least 30% compared with the chow diet (P < 0.001). Fecal calcium excretion correlated positively with fecal fat excretion, presumably because of formation of calcium soaps. Apparent digestibility of phosphorous was higher in all HFDs. This resulted in a decrease of the ratio of apparently digested calcium to apparently digested phosphorous in all HFDs below a ratio of 1:1. Plasma parathyroid hormone was not affected by any diet.
Conclusion:
The alteration of apparent calcium and phosphorus digestibility may affect the impact of HFDs on bone metabolism.
