Food for Thought: On Eating & Inflammation in Rheumatic Disease

ACR CONVERGENCE 2020—At a food-focused ACR Convergence session, rheumatologists shared recent data on the effects of nutrients, herbal supplements and dietary patterns on inflammation, as well as tips for talking with patients about diet and other healthy lifestyle interventions.

Short-Term Fasting
Strict diets usually result in low compliance. “Calorie restriction has been known for a long time to have anti-inflammatory effects, but it is also very difficult to do,” said biogerontologist Valter Longo, PhD, director of the University of Southern California Longevity Institute in Los Angeles. His laboratory team developed a fasting mimicking diet (FMD) low in calories, protein and sugar, and high in unsaturated fats. The FMD includes high levels of prebiotic ingredients in meals, such as leafy greens, tomatoes, carrots and mushrooms, he said.

Valter Longo, PhD

In his group’s recent research, both mice and humans who ate short cycles of the FMD had reduced inflammation or improved symptoms. Mice fed the FMD for five-day cycles had reduced levels of IGF-1, IGFBP-1, glucose and ketone bodies. Middle-aged mice who ate four-day cycles of the FMD twice a month and a normal diet the rest of the month had dramatic increases in white blood cells and lymphoid/myeloid cells, and reduced dermatitis and visceral fat.¹

“Some of these effects appear to be due to a reprogramming of white blood cell counts,” he said. “After eight cycles of the FMD and refeeding, or going back to a normal diet, we saw what looks like a rejuvenation, or at least an increase in white blood cells in the mice back to their youthful levels.”

Symptoms Reversed
In trials a year later, Dr. Longo’s group injected mice with myelin oligodendrocyte glycoprotein to induce a multiple sclerosis (MS) like autoimmune encephalomyelitis. Mice were randomized to eat either three, three-day cycles of FMD alternated with normal feeding, a continuous protein-rich ketogenic diet or a continuous normal diet. All FMD group mice experienced reduced clinical disease severity, and 20% of these mice had reversal of all symptoms. Mice on the ketogenic diet experienced a short-lived, slight decrease in symptoms.²

“We know that early on in the FMD process, there is an increase in corticosteroid levels, sort of a natural, anti-inflammatory effect,” said Dr. Longo. On day 14 of the FMD/refeeding regimen, mice had lower levels of inflammatory lymphocyte infiltrates in their spinal cords, which is associated with reduced demyelination. The FMD mice also appeared to show reduced levels of autoimmune T-regulatory cells. “We see that FMDs can intervene in two ways: increased apoptosis of autoimmune cells, and reduced inflammation. At the same time, there was a reduction in oligodendrocyte precursor cells leading to regeneration,” Dr. Longo said.