Not all approaches to fat loss are equal. When it comes to stubborn subcutaneous fat — the kind that accumulates in the abdomen, hips, and thighs — the mechanisms of local lipolysis differ from systemic fat loss. Citrus polyphenols target these differences.

The Biochemistry of Lipolysis

Lipolysis occurs when fat cells (adipocytes) release stored fat for oxidation. This process is mediated by hormone-sensitive lipase (HSL), which is activated to hydrolyse triglycerides within fat cells. HSL activation is regulated by the cAMP-protein kinase A (PKA) pathway.

However, the expression of alpha-2 adrenergic receptors on adipocytes varies by fat depot. Fat depots containing a high ratio of alpha-2 receptors are more resistant to lipolysis — they respond poorly to normal lipolytic signals. This partially explains why certain areas resist diet and exercise.

Mechanisms of Citrus Polyphenols

Citrus flavonoids like hesperidin and naringin are alpha-2 receptor antagonists. By blocking these receptors, they can increase adipocyte sensitivity to lipolytic signals in stubborn fat depots. Research published in the Journal of Lipid Research found that citrus flavonoid supplementation significantly increased lipolysis rates in participants.

Additionally, citrus polyphenols have been shown to inhibit phosphodiesterase (PDE), the enzyme that breaks down cAMP. By maintaining higher cAMP levels, citrus polyphenols prolong the duration of lipolytic signalling.

Lipogenesis vs Lipolysis

There is a balance between fat storage (lipogenesis) and fat breakdown (lipolysis). SREBP-1c is the primary transcription factor controlling lipogenic gene expression. Hyperinsulinaemia and excessive carbohydrate intake activate SREBP-1c, shifting metabolism toward fat storage.

Research shows that citrus polyphenols can modulate SREBP-1c expression, reducing de novo lipogenesis — the conversion of dietary fats into storage. This provides another mechanism by which citrus polyphenols can affect body composition.

The CitrusBurn Approach

CitrusBurn’s formulation contains standardised doses of citrus polyphenols designed to target alpha-2 adrenergic receptors in stubborn fat depots. This targeted approach aims to address the fat stores that are hardest to reduce even with diet and exercise.