Poor memory from highly processed foods
Already four weeks of a diet with highly processed foods seem to trigger a strong inflammatory reaction in the brain in old age. This can lead to memory problems and promote neurodegenerative diseases such as Alzheimer’s.
A recent study conducted by Ohio State University found that a four-week diet of highly processed foods produced a severe inflammatory response in the brains of aging rats, with signs of memory loss. In addition, supplementing the processed food with the omega-3 fatty acid DHA prevented memory problems and almost completely reduced the inflammatory effects. The corresponding study results were published in the English-language journal “Brain, Behavior, and Immunity”.
Study mimicked human nutrition
The diet of the animals in the study mimicked ready-to-eat human foods, which are often packaged for a long shelf life, such as potato chips and other snacks, frozen meals (pasta dishes and pizzas), and sausage products with preservatives.
Such a highly processed diet is commonly associated with obesity and type 2 diabetes. The new findings now indicate that in the case of highly processed foods, damage to the old brain becomes visible after just four weeks.
Alzheimer’s from processed foods
“The fact that we’re seeing these effects so quickly is a little worrying. These results suggest that consuming processed foods can lead to significant and abrupt memory loss – and in the aging population, rapid memory loss is more likely to lead to neurodegenerative diseases such as Alzheimer’s, ”reports study author Ruth Barrientos of the Ohio State University Institute for Behavioral Medicine Research in a press release.
What was investigated?
For the study, three and 24 month old male rats were randomly divided into different groups. One received normal food (32 percent of the calories from protein, 54 percent from complex carbohydrates based on wheat and 14 percent from fat), a highly processed food (19.6 percent of the calories from protein, 63.3 percent from refined carbohydrates – corn starch, Maltodextrin and sucrose – and 17.1 percent from fat) and the same processed food supplemented with DHA.
What is DHA?
DHA (docosahexaenoic acid) is an omega-3 fatty acid that is found in fish and other seafood together with eicosapentaenoic acid (EPA). The defense against inflammatory reactions is one of the many functions of DHA in the brain. The current study examined for the first time whether DHA can fight inflammation in the brain that is caused by a processed diet.
Higher markers of inflammation from processed foods
Activation of genes associated with a strong pro-inflammatory protein and other markers of inflammation were significantly increased in the hippocampus and amygdala of the older rats that ate only the processed diet compared to young rats that ate a normal diet and elderly rats that ate the processed food supplemented with DHA, the experts explain.
Memory loss thanks to processed foods
The older rats that consumed the processed food showed signs of memory loss in behavioral experiments which did not occur in the young rats. According to the researchers, they also had problems with contextual memory and showed no anticipatory fear behavior in response to warnings. This indicates abnormalities in the amygdala.
What does the amygdala do?
“In humans, the amygdala is involved in memories associated with emotional – fear and anxiety – inducing events. If this region of the brain is disturbed, indications of dangers can be overlooked, which can lead to wrong decisions, ”explains Barrientos.
The results show that DHA supplementation in the processed foods was effective in preventing the increased inflammatory response in the brain and behavioral signs of memory loss. Unfortunately, the researchers do not know the exact DHA dosages, nor the exact amounts of calories and nutrients that the animals consumed, as they all had unlimited access to their food.
Significant weight gain from processed foods
Both age groups gained significant weight with the processed food, with the old animals gaining weight significantly more than the young rats. It found that DHA supplementation had no preventive effect on the weight gain associated with consuming highly processed foods, the team said.
Barrientos emphasizes that people should not interpret the results as a license to consume processed foods as long as they are taken with a DHA supplement. Instead, they should focus on overall dietary improvement to prevent the numerous negative effects of highly processed foods. (as)
Author and source information
This text complies with the requirements of specialist medical literature, medical guidelines and current studies and has been checked by medical professionals.
- Michael J. Butler, Nicholas P. Deems, Stephanie Muscat, Christopher M. Butt, Martha A. Belurya, et al.: Dietary DHA prevents cognitive impairment and inflammatory gene expression in aged male rats fed a diet enriched with refined carbohydrates; in: Brain, Behavior, and Immunity (veröffentlicht Volume 98, November 2021, Pages 198-209), Brain, Behavior, and Immunity
- Ohio State University: How highly processed foods harm memory in the aging brain (veröffentlicht 14.10.2021), Ohio State University
This article is for general guidance only and is not intended to be used for self-diagnosis or self-treatment. He can not substitute a visit at the doctor.