Published in the journal Nutrients, the EuroMed-funded study found that pomegranate extract increased levels of insulin-like growth factor-1 (IGF-1), a hormone that supports normal cell growth and development, but naturally declines with age.
Low levels of IGF-1 have been linked to increased oxidative stress and decreased muscle mass and bone mineral density, as well as an increased risk of cardiovascular disease, type 2 diabetes and metabolic syndrome.
However, very high levels are also associated with negative effects on longevity, with studies showing that excessive levels can increase cancer risk.
This suggests there is a ‘Goldilocks’ zone of IGF-1 levels, according to Andrea Zangara, Scientific Communication Advisor at EuroMed, with EuroMed’s pomegranate extract (marketed as Pomanox) promoting a potentially beneficial increase.
“The modest rise aligns with a physiological ‘sweet spot’, complementing other findings from the same trial: lower IL-6/IL-1β—or reduced inflammaging—reduced systolic blood pressure, and improved cognitive flexibility. Together, these point to a coordinated impact on multiple hallmarks of ageing,” he told NutraIngredients.
What is IGF-1 and how is it linked to healthy aging?
IGF-1 is a hormone which has been increasingly recognized for its role in aging and longevity. However, the researchers from Manchester Metropolitan University, the University of Surrey and the University of Edinburgh say its role remains “controversial”.
While the findings of a large review concluded that increased levels of IGF-1 may play a protective role in vascular aging, a large analysis of nearly 400,000 blood samples has shown that high levels of IGF-1 may also increase the risk of thyroid cancer, in addition to colorectal, breast and prostate cancer.
“From a gerontological perspective, IGF-1 is a double-edged hormone: while very high levels may be undesirable in some contexts, age-related IGF-1 decline is linked to sarcopenia, frailty, vascular dysfunction, and reduced bone mineral density,” Zangara said.
“In older adults, restoring IGF-1 towards mid-physiological levels is associated with better muscle function, metabolic health, and vascular integrity—all key to longevity and healthy ageing,” he added.
Indeed, one large study including more than 550 adults also reported a significant association between higher IGF-1 and longer telomere length, a biomarker of cellular aging.
Telomeres are protective caps at the end of chromosomes that progressively shorten with age, contributing to cellular and biological aging. It has therefore been suggested that telomere length measurement could serve as a promising clinical tool for age-related diseases.
Research suggests that polyphenols may help slow the shortening of telomeres, indicating a potentially protective effect against cellular aging. However, their influence on circulating IGF-1 appears more complex, as they have been shown to both increase and decrease its expression.
The researchers therefore set out to discover whether supplementation with pomegranate extract, which is high in polyphenols, could impact telomere length and circulating IGF-1 levels.
Study details
To conduct their study, Farhat et al. randomly assigned 72 participants between the ages of 55 and 70 to receive either pomegranate extract (Pomanox) or placebo (maltodextrin) for 12 weeks.
Anthropometric measurements, blood pressure readings and blood samples were taken at baseline, halfway through and at the end of the study. Telomere length and serum IGF-1 levels were also measured.
At the end of the study period, circulating IGF-1 levels showed a small but significant increase in the pomegranate extract group, with levels remaining largely unchanged in the placebo group.
“The IGF-1 increase was modest and within physiological ranges for older adults — a level that supports tissue repair and resilience, not pathological overactivation. This confirms the nutritional long-term safety of Pomanox at the studied dose,” Zangara said.
However, telomere length was not affected, contrasting with the findings of previous animal studies. The researchers suggested this could be due to the relatively short study period, or the age range and baseline health status of participants.
“Our study population was physically active and free from chronic disease, which may have influenced the outcomes by reducing the potential for observable improvements in telomere length,” they wrote.
“Notably, telomere length is a relatively stable biomarker that typically changes gradually over long periods, even years. Therefore, the 12-week duration of our study may have been insufficient to detect measurable changes in telomere length.”
They recommended that future research consider assessing telomerase activity, as it may serve as a more sensitive indicator of short-term telomere changes.
Where next?
Overall, the study concluded that the moderate increase in circulating IGF-1 levels is likely to be beneficial without posing adverse effects—emphasizing that this hypothesis requires further investigation with longer human intervention studies.
As the first study to assess the effect of pomegranate extract on telomere length and IGF-1 levels in humans, the researchers noted that it provides important insights into how polyphenol-rich foods and supplements could impact healthy aging
“The findings of this study suggest that daily supplementation with 740 mg of pomegranate extract may elevate IGF-1 levels, indicating its potential to support healthy aging in older adults, although the broader implications for longevity remain to be clarified,” they wrote.
“Future research should focus on long-term, large-scale studies to confirm these effects and further investigate the potential long-term effects of pomegranate extract on counteracting telomere shortening and contributing to improved lifespan.”
Source: Nutrients. doi: 10.3390/nu17182974. “Effects of Pomegranate Extract on IGF-1 Levels and Telomere Length in Older Adults (55–70 Years): Findings from a Randomised Double-Blinded Controlled Trial.” Authors: G. Farhat, et al.
