An agent for atmospheric oxygen-induced coloring of keratin-containing fibers, particularly human hair, which agent contains in a cosmetically acceptable carrier (a) as a dye precursor of a nature-analogous dye at least one indoline derivative, selected from compounds according to the formula (Ila) and/or the physiologically acceptable salts thereof with an organic or inorganic acid, and/or indole derivative are selected from compounds according to the formula (IIb) and/or the physiologically acceptable salts thereof with an organic or inorganic acid, where in the formulas (Ila) and (IIb) - R 1 stands for hydrogen, a C 1 -C 4 alkyl group, or a C 1 -C 4 hydroxyalkyl group, - R 2 stands for hydrogen or a -COOH group, whereby the -COOH group may also be present as the salt with a physiologically acceptable cation, - R 3 stands for hydrogen or a C 1 -C 4 alkyl group, - R 4 stands for hydrogen, a C 1 -C 4 alkyl group or a group -CO-R 6, in which R 6 stands for a C 1 -C 4 alkyl group, and - R 5 stands for a group recited under R 4, and (b) at least one triglyceride of the formula where at least two of the groups R 1, R 2, and R 3 independently of one another stand for pentadec-8-enyl, heptadec-8-enyl, heptadeca-8,11-dienyl, heptadeca-8,11,14-trienyl, tricos-14-enyl, or hencos-11-enyl, and at most one group of the groups R 1, R 2, and R 3 stands for at least one (C 11 to C 25) alkyl group, (C 11 to C 25) alkenyl group, (C 11 to C 25) alkane dienyl group, or (C 11 to C 25) alkane trienyl group, with the proviso that no additional oxidizing agent for the color-forming components is present, characterized in that at least one fruit seed oil, selected from apricot kernel oil, grape seed oil, or rosehip seed oil is present as a source for the compounds of the formula. (a) as a dye precursor of a nature-analogous dye at least one indoline derivative, selected from compounds according to the formula (Ila) and/or the physiologically acceptable salts thereof with an organic or inorganic acid, and/or indole derivative are selected from compounds according to the formula (IIb) and/or the physiologically acceptable salts thereof with an organic or inorganic acid, where in the formulas (Ila) and (IIb) - R 1 stands for hydrogen, a C 1 -C 4 alkyl group, or a C 1 -C 4 hydroxyalkyl group, - R 2 stands for hydrogen or a -COOH group, whereby the -COOH group may also be present as the salt with a physiologically acceptable cation, - R 3 stands for hydrogen or a C 1 -C 4 alkyl group, - R 4 stands for hydrogen, a C 1 -C 4 alkyl group or a group -CO-R 6, in which R 6 stands for a C 1 -C 4 alkyl group, and - R 5 stands for a group recited under R 4, and - R 1 stands for hydrogen, a C 1 -C 4 alkyl group, or a C 1 -C 4 hydroxyalkyl group, - R 2 stands for hydrogen or a -COOH group, whereby the -COOH group may also be present as the salt with a physiologically acceptable cation, - R 3 stands for hydrogen or a C 1 -C 4 alkyl group, - R 4 stands for hydrogen, a C 1 -C 4 alkyl group or a group -CO-R 6, in which R 6 stands for a C 1 -C 4 alkyl group, and - R 5 stands for a group recited under R 4, (b) at least one triglyceride of the formula where at least two of the groups R 1, R 2, and R 3 independently of one another stand for pentadec-8-enyl, heptadec-8-enyl, heptadeca-8,11-dienyl, heptadeca-8,11,14-trienyl, tricos-14-enyl, or hencos-11-enyl, and at most one group of the groups R 1, R 2, and R 3 stands for at least one (C 11 to C 25) alkyl group, (C 11 to C 25) alkenyl group, (C 11 to C 25) alkane dienyl group, or (C 11 to C 25) alkane trienyl group, at least two of the groups R 1, R 2, and R 3 independently of one another stand for pentadec-8-enyl, heptadec-8-enyl, heptadeca-8,11-dienyl, heptadeca-8,11,14-trienyl, tricos-14-enyl, or hencos-11-enyl, and at most one group of the groups R 1, R 2, and R 3 stands for at least one (C 11 to C 25) alkyl group, (C 11 to C 25) alkenyl group, (C 11 to C 25) alkane dienyl group, or (C 11 to C 25) alkane trienyl group,