High-fat diet could cause memory problems in older adults after just a few days

Just a few days of eating a diet with a lot of saturated fat can be enough to cause memory problems and related brain inflammation in older adults, suggests a new study in rats.

Researchers fed individual groups of young and old rats the high -fat diet for three days or for three months to compare how quickly changes take place in the brain versus the rest of the body when eating an unhealthy diet.

As expected on the basis of earlier diabetes and obesity research, eating fatty foods for three months led to metabolic problems, intestinal inflammation and dramatic shifts in intestinal bacteria in all rats compared to those that ate normal cool, while only three days of high fat did not cause large metabolic or intestinal changes.

However, when it came to changes in the brain, researchers discovered that only older rats or now they performed for three months or only three days on the fat-rich diet on memory tests and negative inflammatory changes in the brain.

The results dispel the idea that diet-related inflammation in aging brain is powered by obesity, said senior study author Ruth Barrientos, a researcher at the Institute for Behavioral Medicine Research at Ohio State University. Most research into the effects of fat and processes food on the brain has focused on obesity, but the impact of unhealthy food, regardless of obesity, remains largely unexplored.

“Unhealthy diets and obesity are coupled, but they are not inseparable. We are really looking for the effects of the diet directly on the brain. And we have shown that within three days, long before obesity is capable, an enormous neuro -inflammatoire shifts will occur,” said Barrientity and NeuStrootor and NeuStrootor and NeuStrootor and NeuStrootor and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health and Health Setored Neurwords in Ohio State’s State’s Coleing of Medicine.

“Changes in the body in all animals are slower and are actually not necessary to cause the memory disorders and changes in the brain. We would never have known that brain inflammation is the primary cause of fat -rich due to diet -induced memory disorders without comparing the two timelines.”

The research was recently published in the magazine Immunity and aging.

Years of research in the Barrientos laboratory has suggested that aging results in the long -term “priming” of the inflammatory profile of the brain in combination with a loss of brain cell reserve to bounce back, and that an unhealthy diet can make things worse for the brain in older adults.

Fat is 60% of the calories in the high -fat diet used in the study, which corresponds to a series of common fast food options: food data shows, for example, that fat makes up about 60% of the calories in a McDonald’s double smoky BLT Quarter pounder with cheese or a cheese -cheese burger.

After the animals had for three days or three months on high-rich diets, researchers carried out tests those two types of memory problems that occur in the elderly with dementia based in individual brain areas: contextual memory mediated by the hippocampus (the primary memory center of the brain) and the memory of the cued-farren originated brain).

In comparison with control animals that eat chow and young rats on the fat-rich diet, old rats showed behavior that indicates that both types of memory were affected after just three days of fat food and the behavior continued to exist while continuing with the fat-rich diet for three months.

Researchers also saw changes in levels of a series of proteins mentioned in the brains of old rats after three days of fat food, indicating a disrupted inflammatory response. Three months after they had been to the fat -rich diet, some of the cytokine content had been shifted but remained disrupted and the cognitive problems continued to exist in behavioral tests.

A deviation from baseline inflammatory markers is a negative reaction and has been shown to prevent learning and memory functions. “

Ruth Barrientos, researcher, Institute for Behavioral Medicine Research, The Ohio State University

Compared to rats that eat a normal chow, young and old animals were given more weight and showed signs of metabolic dysfunction-sluggish insulin and blood sugar control, inflammatory proteins in fat (fat) tissue and intestinal microbioma changes after three months on the fat-rich diet. The memory and the behavior and brain tissue of young rats remained unaffected by the cool food.

“These diets lead to obesity-related changes in both young and old animals, but young animals seem more resilient about the effects of the fat-rich diet on memory. We think it is probably due to their ability to activate compensatory anti-inflammatory reactions that the old animals miss,” Barrientos said.

“Also, with glucose, insulin and fat inflammation has all increased in both young and old animals, there is no way to distinguish what memory disorders caused only old animals when you only look at what happens in the body. It is what happens in the brain that is important for the memory reaction.”

This work was supported by subsidies from the National Institute on Aging.

Co-authors are Michael Butler, Stephanie Muscat, Brigitte González Olmo, Sabrina Mackey-Alalfonso, Nashali Massa, Bryan Alvarez, Jade Blackwell, Menaz Bettes and James Demarsh by Ohio State; and Maria Elisa Caetano-Silva, Akriti Shrestha, Robert McCusker and Jacob Allen from the University of Illinois in Urbana-Champaign.