High Fat, Sugar Diets Linked to Cognitive Decline and Depression, New Mouse Study Reveals

An interesting study in mice has recently supported the hypothesis that high fat and sugar diets and cognitive decline like Alzheimer's disease are linked.

The inexpensive, highly processed food that humans consume too much is bad for their health, a ScienceAlert report said.

According to Larisa Bobrovskaya, a neuroscientist and biochemist from the University of South Australia, obesity and diabetes damage the central nervous system, "exacerbating psychiatric disorders and cognitive decline.

The researchers looked for a mouse model that could tell them more about the intersection between Alzheimer's type 2 diabetes and obesity, and they indeed found it.

Diet Linked to Certain Conditions

In the paper published in the Metabolic Brain Disease journal, the study authors said it is commonly known that chronic obesity and type 2 diabetes mellitus are frequently linked to Alzheimer's disease, along with many other comorbidities, including cardiovascular disease and renal dysfunction.

In addition, obesity and type 2 diabetes are increasingly associated with impaired central nervous system function by exacerbating psychiatric and cognitive disorders, including cognitive decline, dementia, and mood disorders.

In a world where eating unhealthily is already incorrectly perceived as a moral failing, this type of result is not likely to help a person with healthier eating habits, although it can provide more tools to be able to investigate this perplexing association, which the team wanted to look into further in the mouse models.

To discover more, the research team looked at adult mice with a mutation in the so-called "human tau protein," also known as P301L, called pR5 mice, along with the wild-type or control mice.

Study in Humans and Mice

In humans, the mutation has been linked to dysfunctions that directly cause the type of nerve degeneration linked to Alzheimer's disease.

In a similar way, in mice, the genes offer study investigators a way to accurately identify mechanisms that associate dementia with other conditions like diabetes, among others.

Essentially, the two groups were fed either a standard or high-fat diet for 30 weeks. Considering mab mice live for roughly 1.5 years, this is a pretty decent part of their life.

The control mice given a high-fat diet put on weight had a heightened risk of displaying behaviors akin to behaviors and exhibited higher levels of tau in the brain.

pR5 Mutation

Tau, in particular, is essential since it is a protein that can turn hyperphosphorylated into "tau tangles," a biomarker of Alzheimer's disease.

For the mice that have pR5 mutation fed the high-fat diet, there was an even more massive slew of problems. They were even more susceptible to obesity, developed glucose intolerance and insulin resistance, and had more depression and behaviors akin to anxiety. More so, their brains exhibited more tau in causing Alzheimer's.

The University of South Australia report said that according to the researchers, their findings reveal that a high-fat diet facilitates the development of peripheral insulin resistance and augments cognitive behavior changes, as well as tau pathology in pR5 transgenic mice.

They added that the probable consequence of high fat diet-induced pathological changes is eventually an aggravation of cognitive deficits in the mice.

Addressing Obesity Epidemic Worldwide

The result might appear a little worrying for the 42 percent of adult Americans suffering from obesity, or the 37 million Americans with type 2 diabetes, although understanding such factors, especially using the mice, is helpful for researchers to unveil new treatments or recommend science-supported changes.

Describing their findings, Bobrovskaya said, they're undermining the essentiality of addressing the obesity epidemic worldwide.

A combination of diabetes, age, and obesity, is very likely to lead to a drop in cognitive abilities, Alzheimer's disease, and other mental health disorders.

Related information about diet for depression is shown on MEDSimplified's YouTube video below:

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