TABLE 2.

Blood plasma substrate and leptin levels in rats fed diets containing 30% calories added as starch, fat, or ketone ester

Values are means in mm ± S.E. unless otherwise indicated where n = 6. For leptin measurements, n = 13 for starch, n = 5 for fat, and n = 12 for ketone ester. For insulin measurements, n = 16 for starch, n = 8 for fat, and n = 15 for ketone ester.

Substrate	Starch	Fat	Ketone ester
Glucose	4.83 ± 0.15	5.24 ± 0.25	2.81 ± 0.27a
d-β-hydroxybutyrate	0.018 ± 0.004	0.031 ± 0.009	2.80 ± 0.19a
Acetoacetate	0.037 ± 0.002	0.045 ± 0.005	0.71 ± 0.09a
Total ketones	0.055	0.076	3.51
Stearic acid (18:0)	0.327 ± 0.042	0.396a ± 0.023	0.315 ± 0.013
Total free fatty acids	0.579 ± 0.45	0.693a± 0.039	0.571 ± 0.025
Plasma leptin ng/ml	3.12 ± 0.46	2.65 ± 0.87	1.83 ± 0.19a
Plasma insulin ng/ml	0.544 ± 0.069	0.135 ± 0.038a	0.263 ± 0.055a

^a p < 0.05 by Mann-Whitney U test comparing starch vs. fat or ketone ester diet.