Eating too much salt can hurt your brain’s ability to learn and remember, but a new study suggests that a natural fiber called inulin might help fix this problem. Researchers gave mice a high-salt diet and found that those who also received inulin showed better memory and learning abilities. The inulin worked by changing the bacteria in the mice’s stomachs, which then produced helpful chemicals that protected the brain from inflammation. While this research was done in mice, it opens the door to a simple dietary solution that could help people who eat too much salt.

The Quick Take

  • What they studied: Whether a natural fiber supplement called inulin could reverse brain damage caused by eating too much salt, and how it works in the body.
  • Who participated: Laboratory mice were divided into groups: some ate a high-salt diet, some ate high-salt diet plus inulin, and some ate normal diets. The exact number of mice wasn’t specified in the abstract.
  • Key finding: Mice that received inulin along with a high-salt diet showed significantly better learning and memory performance compared to mice on high-salt diet alone, suggesting the supplement reversed salt-related brain damage.
  • What it means for you: If these findings hold true in humans, eating inulin-rich foods (like chicory root or Jerusalem artichokes) or taking inulin supplements might help protect your brain if you eat a lot of salty foods. However, this is early research in animals, so don’t rely on it as a replacement for reducing salt intake.

The Research Details

This was an animal study conducted in mice to understand how inulin might protect the brain from salt damage. The researchers created different groups of mice: some ate a normal diet, some ate a high-salt diet, some ate high-salt diet plus inulin, and some received additional salt-like chemicals to test the mechanism. They then tested the mice’s learning and memory abilities using behavioral tests—basically seeing how well the mice could learn and remember tasks.

The scientists also examined what was happening inside the mice’s bodies at a microscopic level. They looked at the bacteria living in the mice’s stomachs (called the microbiota), measured special chemicals these bacteria produce (called short-chain fatty acids or SCFAs), and examined brain tissue to see if inflammation was reduced. They even tested whether giving the mice the beneficial chemicals directly (without the inulin) would produce the same protective effects.

This multi-layered approach allowed researchers to trace the exact pathway from inulin to brain protection, showing that the fiber works by changing gut bacteria, which then produce protective chemicals that reach the brain.

Understanding how inulin works is important because it reveals a connection between what we eat, the bacteria in our stomachs, and our brain health. Rather than just showing that inulin helps, this research explains the ‘why’ and ‘how,’ which makes it more likely that the findings could apply to humans. It also suggests that simple dietary changes might prevent or reverse brain damage from high-salt diets without needing new medications.

This study was published in a reputable peer-reviewed journal focused on food research, which is a positive sign. The researchers used multiple testing methods and examined the problem from different angles, which strengthens their conclusions. However, because this was done in mice rather than humans, results may not directly apply to people. The abstract doesn’t specify the exact number of mice used, which makes it harder to assess the study’s statistical power. Readers should view this as promising early-stage research that needs human testing before making major dietary changes.

What the Results Show

The main finding was that mice receiving inulin showed significantly improved learning and memory compared to mice on a high-salt diet alone. When researchers tested the mice’s ability to learn and remember tasks, the inulin-treated group performed much better, suggesting the supplement reversed the brain damage caused by excessive salt.

The researchers discovered that inulin works by changing the composition of bacteria in the gut. Specifically, inulin helped beneficial bacteria thrive, and these bacteria produced more of a protective chemical called short-chain fatty acids (SCFAs). These SCFAs are like messengers that travel from the gut to the brain, where they reduce inflammation and protect brain cells.

The study also showed that inulin repaired the gut barrier—essentially the wall that separates the intestines from the bloodstream. A damaged gut barrier allows harmful substances to leak into the blood and reach the brain, causing inflammation. By restoring this barrier, inulin prevented this harmful leakage. Additionally, inulin reduced levels of a toxic substance called LPS that normally triggers brain inflammation.

When researchers gave mice the protective chemicals (SCFAs) directly, without the inulin, the mice showed similar brain protection benefits. This confirmed that SCFAs are the key mechanism through which inulin works. The study also found that inulin increased the activity of special receptors on cells that respond to SCFAs, essentially making cells more responsive to these protective chemicals. The research demonstrated that inulin reduced inflammation in the hippocampus, the brain region responsible for learning and memory, by blocking a specific inflammatory pathway (the TLR4/MyD88/NF-κB pathway).

Previous research has established that high-salt diets harm the brain and gut, but effective treatments have been limited. This study builds on existing knowledge about the gut-brain connection by identifying a specific mechanism and proposing a practical solution. The findings align with growing evidence that gut bacteria play a crucial role in brain health and that simple dietary interventions can influence this relationship. The research strengthens the emerging field of ‘psychobiotics’—the idea that certain foods and supplements can improve mental function through gut bacteria.

This research was conducted entirely in mice, so results may not directly translate to humans. Mice have different digestive systems, different diets, and different lifespans than people. The abstract doesn’t specify how long the study lasted or how much inulin was used, making it difficult to know what dose might be appropriate for humans. The study doesn’t address whether inulin would help people who already have salt-related brain damage or only prevent future damage. Additionally, the research doesn’t compare inulin to simply reducing salt intake, which is the most straightforward approach to preventing salt-related health problems.

The Bottom Line

Based on this animal research, inulin appears promising as a potential protective supplement for people who consume high amounts of salt. However, confidence in this recommendation is moderate because human studies haven’t been conducted yet. The most reliable approach remains reducing salt intake overall. If you’re interested in inulin, foods like chicory root, Jerusalem artichokes, and some whole grains naturally contain it. Before taking inulin supplements, especially if you have digestive issues or take medications, consult with a healthcare provider.

This research is most relevant to people who eat high-salt diets and are concerned about brain health, particularly those at risk for cognitive decline. It may also interest people with gut health issues, since the research shows inulin benefits the digestive system. However, people with certain digestive conditions (like IBS or FODMAP sensitivities) should be cautious with inulin, as it can cause bloating. This research is not yet ready to guide treatment decisions for people with existing cognitive impairment.

In the mouse studies, cognitive improvements appeared after the inulin intervention period, but the exact timeline wasn’t specified in the abstract. If similar effects occur in humans, benefits would likely take weeks to months to appear, since changing gut bacteria composition takes time. Don’t expect immediate results—think of this as a long-term preventive strategy rather than a quick fix.

Want to Apply This Research?

  • Track daily salt intake (in milligrams) and inulin consumption (in grams) alongside weekly cognitive function assessments like memory tests or learning speed. Users could log meals and note any changes in mental clarity, focus, or memory over 8-12 weeks.
  • Users could gradually increase inulin-rich foods (chicory root, Jerusalem artichokes, garlic, onions, whole grains) while simultaneously reducing processed foods high in salt. The app could suggest specific meal swaps—for example, replacing salty snacks with inulin-containing alternatives.
  • Implement a 12-week tracking program where users log daily salt and inulin intake, complete weekly cognitive function self-assessments (memory challenges, reaction time tests), and rate subjective mental clarity. Create a dashboard showing correlations between inulin consumption and cognitive performance metrics over time.

This research was conducted in mice and has not yet been tested in humans. The findings are promising but preliminary. Do not use inulin supplements as a replacement for medical treatment of cognitive disorders or as a substitute for reducing salt intake, which remains the most effective approach. People with digestive conditions, pregnant women, and those taking medications should consult a healthcare provider before starting inulin supplements. If you experience cognitive changes or memory problems, seek evaluation from a qualified healthcare professional rather than relying solely on dietary supplements.