Study unlocks new insights on metabolic effects of CurraNZ

A new secondary analysis of 10 clinical trials¹ reveals that CurraNZ® can significantly alter the way your body burns fuel during exercise - but the effects depend on your individual metabolic profile.

Researchers from the University of Chichester analyzed data from 116 participants (47 females and 69 males), ranging from recreationally active individuals to ultra-endurance athletes. Participants consumed the 35% anthocyanin extract in varying doses (105–420 mg of anthocyanins) and durations (single dose to two weeks) before engaging in different forms of exercise including walking, running, and cycling.

The main finding? Your body’s baseline metabolic function - specifically, your respiratory exchange ratio (RER), which reflects the balance of carbohydrate and fat usage during exercise - plays a major role in determining how blackcurrant extract affects your fuel metabolism.

Key Takeaways:

• NZBC extract boosts fat oxidation in most individuals: The majority of participants showed an increase in fat oxidation and a corresponding decrease in carbohydrate oxidation during exercise after taking NZBC extract.
• Baseline metabolism matters: The stronger your natural tendency to burn carbs over fats (a higher RER), the more likely NZBC will shift your metabolism toward fat burning. In contrast, individuals with an already low RER—meaning they naturally burn more fat—were more likely to show the opposite effect, with reduced fat oxidation and increased carbohydrate usage after supplementation.
• Consistent effects across sexes: Both men and women experienced similar metabolic shifts, with no significant sex-based differences in response to the supplement.
• Personalized nutrition potential: These findings point to a more individualized approach to supplementation. NZBC extract could offer tailored benefits for athletes and active individuals depending on their starting metabolic profile.

Professor Mark Willems (left), who led the study at the University of Chichester, says “In sports nutrition research, it is important to consider the individual responses. Our consistent attention to the metabolic responses by intake of anthocyanin-rich blackcurrant in many studies has now allowed us confirm that for most the intake will have a fat-burning effect during different kind of exercises”. 

Why This Matters

Fat oxidation during exercise is associated with improved endurance and metabolic health. The ability of CurraNZ to support fat utilization could be particularly beneficial for athletes looking to optimize performance, as well as for individuals aiming to improve body composition or energy efficiency during physical activity.

However, the nuanced, personalized nature of the response—based on pre-existing metabolic traits—highlights the growing need for personalized sports nutrition. NZBC isn’t a one-size-fits-all solution, but rather a targeted tool that may help certain individuals unlock greater energy potential from their workouts.

As research into plant-based performance enhancers continues to grow, New Zealand blackcurrant stands out as a promising natural aid for metabolic modulation—especially when used with an understanding of individual variation.

Reference

1.    M Willems, M Cook, Alterations of Exercise-Induced Carbohydrate and Fat Oxidation by Anthocyanin-Rich New Zealand blackcurrant are associated with the Pre-Intervention Metabolic Function: A Secondary Analysis of Randomized Crossover Trials, Nutrients, 2025, 17(6), 997, https://doi.org/10.3390/nu17060997