Often perceived as a mere aesthetic nuisance, cellulite results from a relatively complex biological phenomenon involving changes in the structure of the subcutaneous connective tissue. It manifests as localized fat accumulation and/or water retention, potentially accompanied by microcirculatory alterations. These modifications create a “orange-peel” appearance on the thighs, hips, or buttocks, particularly common in women. Contrary to popular belief, the cellulite is not necessarily associated with excess weight or poor lifestyle habits, even though these factors can indeed exacerbate it. It’s quite difficult to completely eliminate the cellulite without resorting to surgery, some cosmetic active ingredients appear to help, including L-carnitine.
The primary function of L-carnitine is to transport long-chain fatty acids into the mitochondria, where they are oxidized to produce energy.
When applied to the skin, L-carnitine is believed to promote lipid breakdown by stimulating the uptake of fatty acids into adipocyte mitochondria. The carnitine–palmitoyltransferase 1 (CPT1) enzyme complex, located on the outer mitochondrial membrane, catalyzes the formation of an acyl-carnitine complex, which then crosses the inner membrane via carnitine–acylcarnitine translocase. Once inside the mitochondrion, acyl-carnitine is converted back to acyl-CoA, which enters the β-oxidation cycle, resulting in a reduction of adipocyte volume. This stimulation of lipid catabolism could theoretically help reduce excess fat in areas affected by cellulite.
Furthermore, L-carnitine is involved in the regulation of oxidative stress, often observed in fibrotic and inflamed tissues characteristic of cellulite. It can limit the accumulation of lipid peroxidation products, such as malondialdehyde, and may protect connective structures, particularly collagen and elastin fibers, against free radical–induced degradation.
The efficacy of L-carnitine in reducing cellulite was evaluated in a clinical trial investigating a product containing, among other ingredients, L-carnitine and caffeine. In conjunction with a low-calorie diet and a weekly regimen of 150 minutes of walking, seven participants allocated into two groups applied the treatment or a placebo daily for 28 days. Researchers measuredthigh circumference and local fat mass via dual-energy X-ray absorptiometry scans. The results, presented in the table below, demonstrate greater reductions in the group receiving the L-carnitine–based product.
Thigh circumference and fat mass before and after the study.
Source: RODRIGUEZ J. et al. Effects of a topical lotion containing aminophylline, caffeine, yohimbe, L-carnitine, and gotu kola on thigh circumference, skinfold thickness, and fat mass in sedentary women. Journal of Cosmetic Dermatology (2019).
This study suggests that the topical application of L-carnitine, combined with other lipolytic agents, may amplify the effects of a low-calorie diet and moderate physical activity on reducing localized fat deposits.
These encouraging results nevertheless need to be qualified. The participant sample was very small, including only seven individuals, which makes the conclusions hardly generalizable to the broader population. Moreover, the product formulation contains several ingredients recognized for their effects on fat metabolism, such as caffeine. It is therefore impossible to determine with certainty what proportion of the observed effects can be specifically attributed to L-carnitine. Further studies, with larger sample sizes and controlled formulations, would be necessary to accurately assess the efficacy of L-carnitine on cellulite.
Coenzyme Q10 and L-carnitine for cellulite: a winning duo?
The combination of L-carnitine and coenzyme Q10 is frequently promoted in products targeting cellulite. Nevertheless, despite its popularity, this combination is not based on any independent scientific study. As a reminder, coenzyme Q10, or ubiquinone, is a fat-soluble molecule known for its antioxidant properties and its role in mitochondrial energy production via the Krebs cycle. It could theoretically protect skin tissues against oxidative stress, and thereby, to some extent, prevent cellulite. However, in the absence of clinical data, it is impossible to assert that coenzyme Q10, with or without L-carnitine, can reduce cellulite.