# Nutrition and diets in Lewy body dementia
Nutrition plays a role in Lewy body dementia, both from the perspective of supporting the disease process and from practical daily care. Recent research points to associations between certain dietary choices, body composition, and disease progression. This tab describes which diets and nutritional patterns are being investigated or recommended for this condition.
Polyunsaturated fatty acids
ResearchediPositive results in clinical studies, not yet standard treatment
Polyunsaturated fatty acids (PUFAs) are fats found primarily in fish, nuts, seeds, and certain plant-based oils. These fats are important for brain structure and inflammatory processes.
A 2026 study showed that in Lewy body dementia there are specific associations between body mass index (BMI) and the level of polyunsaturated fatty acids in blood — associations that differ from those in Alzheimer's disease. This suggests that the fat profile in the blood in Lewy body dementia responds differently than in other forms of dementia. The study suggested that fatty acid composition may be relevant to the disease process, but further studies are needed to determine whether nutritional intervention with these fats is truly beneficial.
A recent review (2025) on plant bioactive compounds pointed to potential benefits of certain plant-derived anti-inflammatory components, of which polyunsaturated fatty acids can be a part, but evidence in this disease is still limited.
**Known risks:** Food very rich in certain fatty acids may contribute to weight changes in sensitive individuals; interaction with medication is unlikely but should be discussed with your healthcare provider.
Mediterranean dietary pattern
ResearchediPositive results in clinical studies, not yet standard treatment
The Mediterranean pattern consists of lots of vegetables, fruit, whole grains, nuts, olive oil, and moderate fish consumption, with less red meat and dairy products. This pattern has been investigated for many neurodegenerative conditions.
For Lewy body dementia, there are specific indications in the literature that neuroinflammation (inflammation in the nervous system) plays a role — a mechanism that could potentially be influenced by Mediterranean eating. An integrative review (2025) on inflammatory mechanisms in various forms of dementia pointed to shared inflammatory pathways. The Mediterranean pattern is traditionally aimed at reducing this type of inflammation, but studies specifically in Lewy body dementia are still lacking.
**Known risks:** No evidence of harmful interactions, but this pattern requires nutritional variety and attention to adequate calorie and protein intake — points that are important in dementia.
Coffee and caffeine
ResearchediPositive results in clinical studies, not yet standard treatment
Coffee and caffeine are widely used in daily life and can influence concentration, alertness, and sleeplessness.
An analysis (2025) of American health data (NHANES) examined coffee consumption and cognitive ability in older adults. Although this did not specifically look at Lewy body dementia, the data showed that moderate caffeine use in an aging population was associated with better cognitive performance. However, this does not automatically say anything about the course of Lewy body dementia itself.
In Lewy body dementia, some patients may be sensitive to sleep disruption and sleeplessness, which can be worsened by caffeine. This is particularly relevant because sleep disorder is an important symptom of the disease.
**Known risks:** Caffeine can worsen sleeplessness and restlessness. In people with autonomic dysfunction (which occurs in Lewy body dementia), caffeine can affect blood pressure. Discuss caffeine use with your doctor, especially if you experience sleep problems.
Protein-rich nutrition
ResearchediPositive results in clinical studies, not yet standard treatment
Protein-rich foods support the maintenance of muscle mass and body composition. This is particularly relevant because research has shown that malnutrition and loss of muscle mass occur in Lewy body dementia.
A retrospective study (2026) on malnutrition and correlates in Lewy body dementia showed that malnutrition and poor nutritional status occur and are linked to clinical features of the disease. This underscores the importance of adequate protein intake for maintaining body composition. Further research (2025) on 'intrinsic capacity' (the body's own ability) showed that physical strength and nutritional status are important for the functioning of patients with Lewy body dementia.
Metabolic rate (basal metabolic rate) also proved (2025) to play a protective role against cognitive decline. This suggests that maintaining healthy body composition through adequate nutrition may be important.
**Known risks:** No specific risks of high-protein diet itself, but regular consultation with a dietitian is important to ensure that the balance with other nutrients is maintained and that aspiration does not become a problem.
Fasting and intermittent fasting
UnproveniNo scientific evidence that it works
Periodic fasting (for example intermittent fasting) is a pattern in which one eats no or limited food for certain periods. This pattern is being investigated for various neurodegenerative disorders.
For Lewy body dementia, there are no specific, reliable studies showing that periodic fasting is beneficial or harmful. Since malnutrition and weight loss already occur in this disease, caution is warranted.
**Known risks:** Periodic fasting can lead to weight loss and malnutrition — risks that are already elevated in Lewy body dementia. This pattern is generally not recommended without very close medical supervision.
Plant-active substances and supplements
ExperimentaliOngoing in study setting, outcome still unknown
Plant-active substances are bioactive components from plants (polyphenols, flavonoids, etc.) that have anti-inflammatory or antioxidant properties. A recent review (2026) on neurodegeneration and plant-based bioactives showed that certain substances may potentially be effective against neurodegenerative processes in the laboratory and in animal models.
Research (2026) was also conducted on a traditional Japanese herbal mixture (Tsumura Ninjin'yoeito) for loss of appetite and apathy in both Alzheimer's and Lewy body dementia. This showed some benefits for appetite and motivation, but the evidence is still limited and this is a very specific intervention.
Research into plant-active substances in this disease is still in an early stage. Many promises from laboratory work do not translate into actual clinical benefits in humans.
**Known risks:** Some plant-based supplements may have interactions with medications used for Lewy body dementia. This should always be discussed with your doctor.
Gut health and dietary fiber
ResearchediPositive results in clinical studies, not yet standard treatment
A healthy gut and gut flora may influence brain function via the so-called gut-brain axis. Dietary fiber feeds the beneficial bacteria in the gut.
Research (2024 and 2025) showed that patients with Lewy body dementia have different gut bacterial composition than healthy control groups. A review (2025) on the gut-brain connection in neurological diseases pointed out that dysbiosis (disrupted gut flora) may contribute to neurodegeneration. At the same time, an analysis (2025) showed that diet influences gut flora in Parkinson's patients — relevant because Lewy body dementia and Parkinson's have many similarities.
This suggests that nutrition that supports gut flora (through adequate fiber, diverse plant-based diet) could theoretically be beneficial, but the evidence is still indirect and not specifically targeted at Lewy body dementia.
**Known risks:** A sudden increase in dietary fiber can cause intestinal cramping and constipation. Since autonomic dysfunction (including constipation) can be part of Lewy body dementia, dietary changes should be gradual and guided.
Weight management and calorie requirements
ResearchediPositive results in clinical studies, not yet standard treatment
Maintaining a healthy weight and adequate calorie intake is important in Lewy body dementia, because undernutrition and weight loss prevent complications and are associated with faster functional decline.
Research (2026) on undernutrition showed that approximately a portion of patients with Lewy body dementia are undernourished and that this is linked to disease progression. Research (2025) on basal metabolic rate suggested that maintaining metabolically healthy body composition may be protective.
In practical terms, this means that regular food intake, adequate calories and monitoring of weight are part of the care plan for this disease.
**Known risks:** No risks from appropriate calorie intake, but attention is needed for choking (dysphagia), which can occur as the disease progresses.
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Finally
Food choices in Lewy body dementia are not a one-time matter but tailored. They should be discussed with your GP, neurologist or specialist and ideally also with a dietitian who has experience with neurodegenerative disorders. Preventing undernutrition, maintaining adequate nutrition, paying attention to gut health and being careful with dramatic dietary changes are practical points to consider. Scientific knowledge about specific diets in this disease is growing, but there is no miracle diet. Regular monitoring and adjustment to what works for you, in consultation with your care team, remains most important.
_This information never replaces a doctor's judgment. Always discuss your situation with your own healthcare provider._