Whereas the ketogenic weight loss program initially bought its begin as a therapeutic method for the administration of epilepsy1, researchers rapidly recognized different potential advantages of the high-fat, low-carb routine. Keto dieters could take pleasure in weight reduction, decrease blood stress, and lowered danger of metabolic illness because of their way of life alternative.
However the unfavorable unwanted side effects of a keto weight loss program have additionally begun to floor, with specialists at UC Davis citing the potential for nutrient deficiencies, unfavorable results on coronary heart well being, gastrointestinal troubles, and extra2. And now one other probably worrisome aspect impact of keto has come to gentle: New analysis in Neuron appears to indicate that simply two days on a high-fat weight loss program may scramble the hippocampus’ potential to type new recollections3.
What Is a Keto Weight loss program?
A keto or ketogenic weight loss program includes consuming high-fat, low-carbohydrate meals. The objective of the keto weight loss program is to succeed in a metabolic state of ketosis, by which the physique begins to make use of fats for vitality. Slightly than glucose (carbohydrates and sugar) being your major mind meals, throughout ketosis your mind fuels up on fats.
This course of makes your physique extra environment friendly at burning fats for vitality, which might help promote weight reduction and decrease your danger for sure illnesses. However as new analysis piles up, many are starting to marvel if there are dangers that would outweigh the advantages of keto.
How Keto May Have Destructive Repercussions on Reminiscence
Proof connecting excessive fats consumption to poor reminiscence operate has been stacking up for years. A 2017 examine in PLoS ONE confirmed that 4 days on a high-fat weight loss program may result in hassle with spatial studying and recall. Analysis revealed in 2017 in Neurobiology of Growing older discovered {that a} high-fat weight loss program may result in reminiscence issues in as little as three days4. And 2018 analysis in Scientific Stories confirmed {that a} high-fat weight loss program may impair episodic reminiscence (the power to recollect particular occasions or experiences) inside only a day5.
Concerningly, the 2 latter research have been performed on rodents solely consuming about 60 p.c of their energy from fats. Since a keto weight loss program really requires a good larger fats consumption (as much as 80 p.c of caloric consumption from fats), it’s no shock that this can be a trigger for concern.
In response to a 2024 examine in Mind, Habits, and Immunity, if a high-fat weight loss program can result in reminiscence malfunction, it’s largely as a consequence of a pure inflammatory response within the mind6. Researchers discovered {that a} high-fat weight loss program led to overproduction of interleukin-1 beta, an “alarm chemical” launched by immune-like cells within the mind to set off irritation. This irritation then blocks the mind from creating and storing recollections, significantly emotional ones.
The brand new analysis in Neuron confirms these findings and sheds extra gentle on the mechanism behind it. The researchers targeted their consideration on a small set of nerve cells in part of the hippocampus chargeable for forming new recollections and separating related experiences. They noticed that for mice consuming a weight loss program made up of 58 p.c fats, these cells over-fired, scrambling regular patterns and messing with reminiscence formation and storage.
A Excessive-Fats Weight loss program Doesn’t Essentially Imply Reminiscence Woes
Whereas this knowledge may lead some to swear off the keto weight loss program, it’s extra complicated than it appears. The researchers behind each of the latest research posited that it wasn’t really the high-fat weight loss program itself that induced reminiscence malfunction, however slightly linked unwanted side effects.
Within the case of the 2024 examine, the researchers discovered that by blocking interleukin-1 beta from docking on its receptor, they have been capable of circumvent the reminiscence issues. This confirmed that the perpetrator wasn’t the high-fat weight loss program itself, however slightly the ensuing irritation. Equally, within the 2025 examine, the researchers discovered that they might reverse the ensuing reminiscence loss by growing glucose within the mind — even when the high-fat weight loss program continued.
The Alzheimer’s Discrepancy
The hyperlink between fats and reminiscence grows much more complicated once you look at the distinctive case of Alzheimer’s. Some analysis confirms the hyperlink between excessive fats consumption and reminiscence loss, like a 2014 examine in Neurobiology of Growing older that appeared to indicate that 4 months on a high-fat weight loss program led to sooner reminiscence loss in mice engineered to develop Alzheimer-like mind modifications7. A 2024 examine in Mind, Habits, and Immunity additionally confirmed that even brief spans of high-fat consuming may worsen reminiscence in Alzheimer’s mannequin mice8.
However different analysis has proven the alternative, with two analysis critiques — one in 2021 analysis overview9 and the opposite in 202410 — showcasing the helpful results of a ketogenic weight loss program on sufferers with Alzheimer’s illness. One October 2025 examine from the College of Missouri discovered {that a} high-fat weight loss program like keto may assist protect mind well being and even sluggish cognitive decline for Alzheimer’s sufferers with the APOE4 gene, the strongest identified genetic danger issue for late-onset Alzheimer’s illness11.
Since these with the APOE4 gene battle to transform glucose into mind vitality, the researchers defined {that a} keto weight loss program would permit the mind to make use of ketones in its place gas supply to scale back cognitive decline.
Understanding the Hyperlink Between Fats Consumption and Reminiscence
So with all this conflicting analysis, what’s the actual reply? There are two main takeaways from this bounty of analysis. Firstly, there’s no one-size-fits-all method to the hyperlink between weight loss program and reminiscence.
“As an alternative of anticipating one answer to work for everybody, it is likely to be higher to contemplate a wide range of elements, together with somebody’s genotype, intestine microbiome, gender and age,” stated Ai-Ling Lin, a professor within the College of Missouri College of Medication and writer of the 2025 examine.
Kathleen Benson, CSSD, CPT, RDN at VNutrition, echoes this concept. “We nonetheless don’t totally perceive how completely different fats sorts and meals sources work together with mind irritation over time,” she explains. “Particular person elements like genetics, hormone standing, digestive well being, and metabolic flexibility probably play a giant position too.”
Think about the High quality of Your Fat
Secondly, and maybe even extra important, is to contemplate the significance of general weight loss program and the standard of the fats consumed. In spite of everything, the weight loss program adopted within the 2017 PLoS ONE examine wasn’t simply excessive in fats but additionally in added sugar — which emulated not keto, however a mean American weight loss program. Within the phrases of the Middle for Meals as Medication & Longevity, the 60 p.c fats weight loss program adopted in lots of of those research doesn’t simply correspond to a keto weight loss program but additionally to “a human weight loss program heavy in quick meals, fried meals, and processed meats12.”
“’Excessive fats’ is a giant umbrella,” explains Benson. “A Western, ultra-processed high-fat sample can increase irritation and might impair hippocampal-dependent reminiscence. A well-formulated ketogenic weight loss program that facilities extra-virgin olive oil, nuts, seeds, avocado, eggs, and fish usually developments the opposite approach.”
There’s no denying the truth that, as Benson explains, “the mind does desire glucose” as its gas supply. That stated, “it might probably run nicely on ketones throughout dietary ketosis.”
“Extremely processed, high-fat patterns are the principle danger,” she continues. “A rigorously designed, minimally-processed ketogenic method will be impartial and even useful in choose sufferers, particularly when insulin resistance is a part of the image.”
Constructing a Mind-Boosting Keto Weight loss program Plan
A keto weight loss program isn’t essentially one of the simplest ways ahead for everybody, so you must communicate to healthcare professionals about whether or not it’s an excellent plan for you. And whether it is, there are particular approaches to raised reduce your possibilities of reminiscence decline.
Benson suggests constructing meals round antioxidant-rich plant meals like greens, herbs, and fruits. Search for meals naturally loaded with varied colours, which present that you simply’re getting a variety of nutritional vitamins, minerals, and antioxidants.
“For these following strict ketosis, lower-sugar choices similar to berries have a tendency to suit extra simply,” she says, “however all fruits present useful nutritional vitamins, fiber, and phytonutrients.”
She additionally suggests searching for out clear and wholesome fats sources. “Prioritize omega-3s, unsaturated fat, and a wide range of minimally processed meals,” she says.
Monitor Sugar Consumption and Hydration
In the meantime, Naturopathic Physician Serena Goldstein notes that these following a wholesome keto weight loss program may also think about monitoring their blood sugar. You’ll be able to completely nonetheless reap the advantages of a keto weight loss program, however this can be a key step to make sure that hypoglycemia doesn’t turn out to be a priority — particularly in the beginning of a life-style journey.
“Within the keto weight loss program that is generally mitigated by with the ability to have fruit, limiting or negating alcohol or caffeine, and addressing any way of life elements and stress/considerations that may very well be affecting their well being,” she says.
Benson provides that staying hydrated and conserving electrolytes balanced is essential. She additionally recommends “avoiding excessive calorie restriction,” which may hurt mind operate and have an effect on long-term sustainability of any weight loss program, keto included.
Sources:
- https://pmc.ncbi.nlm.nih.gov/articles/PMC8153354/
- https://well being.ucdavis.edu/weblog/good-food/what-is-the-keto-diet-and-can-it-be-beneficial-for-you/2025/05
- https://information.unchealthcare.org/2025/09/eating-junk-food-increases-risk-of-cognitive-decline-study-shows/
- https://pubmed.ncbi.nlm.nih.gov/28719855/
- https://www.nature.com/articles/s41598-018-30265-4
- https://pubmed.ncbi.nlm.nih.gov/37838078/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC4024197/
- https://pubmed.ncbi.nlm.nih.gov/39043341/
- https://pmc.ncbi.nlm.nih.gov/articles/PMC8755961/
- https://www.sciencedirect.com/science/article/pii/S1279770724003932
- https://www.sciencedaily.com/releases/2025/10/251021083646.htm
- https://foodmedcenter.org/your-brain-on-fat-how-high-fat-diets-hijack-your-memory-in-just-days/
