Use of a composition, comprising (i) physiologically acceptable, metabolic lipids, selected from the group consisting of butanoic acid and longer chain fatty acids, more preferably selected from the group consisting of pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanoic acid, eicosanoic acid, heneicosanoic acid, docosanoic acid, tricosanoic acid, pentacosanoic acid, hexacosanoic acid, heptacosanoic acid, octacosanoic acid, nonacosanoic acid, triacontanoic acid, henatriacontanoic acid, dotriacontanoic acid, tritriacontanoic acid, tetratriacontanoic acid, pentatriacontanoic acid, hexatriacontanoic acid, myristoleic acid, palmitoleic acid, oleic acid, elaidic acid, vaccenic acid, linoelaidic acid, α-linolenic acid, arachidonic acid, eicosapentanoic acid, erucic acid, docosahexanoic acid, stearidonic acid, docosapentanoic acid, eicosatetranoic acid and docosahexanoic acid, more preferably selected from the group consisting of octadecanoic acid, dodecanoic acid, hexadecanoic acid and oleic acid, most preferably hexadecanoic acid and octadecanoic acid; and (ii) physiologically acceptable, preferably biodegradable controlled release (CR) compounds selected from the group consisting of poly(lactic-co-glycolic acid) (PLGA), polylactic acid (PLA), polycaprolactone (PCL), poloxamers, polyethylene glycol (PEG)-PLGA co-polymers, combinations of PEG and PLGA, combinations of PLA and PEG, preferably PLA-PEG-PLA, combinations of PLGA and poloxamers, dextran, alginate and polymethacrylate, preferably PLA, PLGA and PEG-PLGA combinations, more preferably PLGA and PLA, most preferably PLGA, wherein the lipids are cell-free and the CR-compounds release the metabolic lipids over a delayed time period under physiological conditions, for cosmetic treatment selected from the group consisting of cosmetic fat tissue expansion and cosmetic fat tissue repair. (i) physiologically acceptable, metabolic lipids, selected from the group consisting of butanoic acid and longer chain fatty acids, more preferably selected from the group consisting of pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanoic acid, eicosanoic acid, heneicosanoic acid, docosanoic acid, tricosanoic acid, pentacosanoic acid, hexacosanoic acid, heptacosanoic acid, octacosanoic acid, nonacosanoic acid, triacontanoic acid, henatriacontanoic acid, dotriacontanoic acid, tritriacontanoic acid, tetratriacontanoic acid, pentatriacontanoic acid, hexatriacontanoic acid, myristoleic acid, palmitoleic acid, oleic acid, elaidic acid, vaccenic acid, linoelaidic acid, α-linolenic acid, arachidonic acid, eicosapentanoic acid, erucic acid, docosahexanoic acid, stearidonic acid, docosapentanoic acid, eicosatetranoic acid and docosahexanoic acid, more preferably selected from the group consisting of octadecanoic acid, dodecanoic acid, hexadecanoic acid and oleic acid, most preferably hexadecanoic acid and octadecanoic acid; and (ii) physiologically acceptable, preferably biodegradable controlled release (CR) compounds selected from the group consisting of poly(lactic-co-glycolic acid) (PLGA), polylactic acid (PLA), polycaprolactone (PCL), poloxamers, polyethylene glycol (PEG)-PLGA co-polymers, combinations of PEG and PLGA, combinations of PLA and PEG, preferably PLA-PEG-PLA, combinations of PLGA and poloxamers, dextran, alginate and polymethacrylate, preferably PLA, PLGA and PEG-PLGA combinations, more preferably PLGA and PLA, most preferably PLGA, <EOS>