Calorie Restriction, Ketogenic Diets Reduce Biological Aging in RRMS

Adults with relapsing-remitting multiple sclerosis (RRMS) may benefit from fasting-mimicking diets, which can counter accelerated biological aging processes associated with the condition, according to study results presented at the Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) Forum 2025, held in West Palm Beach, Florida from February 27 to March 1.

Previous studies have shown that biological age based on calculated metabolomic age is accelerated among individuals with MS, affecting health outcomes and quality of life in this patient population. Lifestyle interventions, including fasting-mimicking diets such as the ketogenic diet and intermittent caloric restriction, are interventions that have been associated with reduced inflammation, improved function of the immune system, and better clinical outcomes in individuals with MS. However, studies have not indicated whether improved MS health outcomes correlate to these dietary interventions effectively altering biological age.

Researchers at Johns Hopkins University and University of Virginia analyzed the metabolome profiles obtained from plasma samples of 75 participants with RRMS in 2 previously conducted dietary intervention studies to assess whether the dietary interventions were effective in reversing metabolomic aging.

In the first study, 36 adults with RRMS were randomly assigned to 3 dietary intervention groups for 8 weeks — reduced caloric intake by 22%; intermittent reduction of caloric intake by 75% twice weekly; and maintained weight-stable diet without restricting any daily caloric intake. In the second study, 39 adults with RRMS followed a modified Atkins ketogenic diet for 6 months.

The researchers used a previously published metabolomic age prediction model based on the metabolomic profiles from 11,977 healthy adults to calculate the metabolomic age for each trial participant with RRMS.

Compared with individuals in the weight-stable control group, those in the intermittent caloric restriction diet group demonstrated significantly reduced metabolomic age (mean metabolomic age difference per week: -1.25 years; 95% CI, -2.46 to -.04 years; P =.04).

Individuals with higher biological ages showed a reduction in effector memory T cells (-3.03% per every 1 unit of age acceleration; 95% CI, -5.76 to -.30; P =.02) and an increase in CD4 naïve cells (4.18% per every 1 unit of age acceleration; 95% CI, .001 to 8.35; P =.05).

Similarly, individuals adhering to the ketogenic diet for 6 months showed an average reduction of 1.12 years in metabolomic age for every month on the diet (95% CI, 0.36 to 1.89 years; P =.007).

“Intermittent calorie restriction and ketogenic diets significantly reduced [metabolomic age] in people with RRMS, demonstrating that the accelerated biological aging observed in [people with] MS can be modified through the use of fasting-mimicking diets,” the researchers concluded.