mind
Memory Impairment
Adverse effectMemory impairment is an adverse effect involving reduced memory performance. A person may notice greater difficulty learning, retaining, or recalling information than usual, which can appear as memory loss or fewer words remembered.
Memory Impairment is categorized as a mind-related effect.
These are research findings, not promises. Most options have little evidence, and results differ from person to person.
What can cause it
How likely each one is to cause it, most likely first.
Ice Bath / Cold PlungepracticeUnclear
Based on 3 studies. Strongest study: a systematic review of studies.
A review of randomized and non-randomized human studies reported that acute exposure to cold water at 10 °C impaired working memory and attention.
Open the Ice Bath / Cold Plunge pageTai ChipracticeUnclear
Based on one study. Strongest study: a systematic review of studies.
A 2025 systematic review reported difficulty executing and remembering Tai Chi movements; the study designs in the pooled analyses were not recorded.
Open the Tai Chi pageFastingpracticeUnclear
Based on one study. Strongest study: a systematic review of studies.
Open the Fasting page
The expert view shows every study, dose protocol and source.
What can cause it
Interventions reported to bring this on3 listedHighest probability
- →PracticesIce Bath / Cold PlungeCertaintyLowSourceClinical3 other sources
A review of randomized and non-randomized human studies reported that acute exposure to cold water at 10 °C impaired working memory and attention.
Who was studied
- Healthy people and patients
Open Ice Bath / Cold PlungeStudy result
Jones et al. found that acute exposure to cold water (10 °C) impaired both WM and attention
- →PracticesTai ChiCertaintyLowSourceClinical1 other source
A 2025 systematic review reported difficulty executing and remembering Tai Chi movements; the study designs in the pooled analyses were not recorded.
Who was studied
- People with a condition
Open Tai ChiStudy result
Difficulty executing and remembering Tai Chi movements
- →PracticesFastingCertaintyLowSourceClinical1 other source
A 2026 systematic review associated very restrictive eating windows (≤10 h) and prolonged fasting (>12.38 h) with lower cognitive scores. One example reported MMSE scores of 22.45 ± 4.63 versus 24.97 ± 4.24 (p<0.001) in the time-restricted feeding group; the review also reported 58% increased cardiovascular mortality.
Who was studied
- Healthy people and patients
Open FastingStudy result
However, very restrictive eating windows (≤10 h) and prolonged fasting (>12.38 h) were associated with adverse outcomes, including lower cognitive scores and 58% increased cardiovascular mortality. [e.g., MMSE lower in TRF group: 22.45 ± 4.63 vs 24.97 ± 4.24, p<0.001]
How to read the evidence
Evidence tier — overall strength of the evidence for the whole compound
- StrongWell established — backed by strong, consistent human research.
- ModerateSome genuine support, but mostly from small or lower-quality studies. Promising, not proven.
- PreliminaryEarly-stage evidence — a promising hypothesis, not an established effect yet.
- LimitedVery limited evidence — treat this as a hypothesis, not proof.
- InsufficientNot enough good evidence to draw conclusions yet.
Certainty — how sure we can be that the effect is real
- Very highVery sure — strong, consistent evidence
- HighFairly sure — consistent evidence from good studies
- MediumModerately sure — new studies could change this
- LowNot sure — little or mixed evidence
- Very lowVery unsure — almost no usable evidence
Source — where the data comes from
- Meta-analysisPooled analysis of many trials — the strongest evidence
- RCTRandomized controlled trial — a strong human study design
- ClinicalA human clinical study
- Reference knowledgeFrom general health-science or pharmacology references, not a study of this exact claim
- Animal researchStudied in animals, not humans
- Community reportsAggregated user reports — anecdotal signal, not evidence
- TheoreticalMechanism-based reasoning, not yet tested
Study grade — quality of each underlying study (A best, D weakest)
- AHigh-quality — strong, consistent human trials
- BGood — solid evidence with some limitations
- CModerate — limited, small, or mixed-quality studies
- DWeak — preliminary, indirect, or animal-only
Confidence — how strongly the sources back a finding
A 0–100 score from study quality and agreement
Most supplement evidence is graded C–D. Read it as preliminary signal, not proof.
Full write-up
What is it
Memory impairment is an adverse effect involving reduced memory performance. A person may notice greater difficulty learning, retaining, or recalling information than usual, which can appear as memory loss or fewer words remembered. It is not the same as improved concentration or alertness, although attention may also be affected in some reports. Examples associated with this outcome include CBD (Cannabidiol), Resveratrol, and Ice Bath / Cold Plunge.
How interventions help
The findings point to several different kinds of exposures rather than one shared intervention pattern. Some concerns were observed after an acute exposure, meaning they appeared in relation to a single episode rather than a demonstrated need for continuous use. One clinical finding involved CBD (Cannabidiol) at 1000 mg after an acute single dose. Cold-water exposure was also assessed as an immediate experience, with reported effects involving working memory and attention. These observations do not establish how long any change lasts after the exposure ends.
For other substances, the available information does not define a typical dose, duration, onset, or whether the effect persists after stopping. As a result, it is not possible to infer that taking an intervention daily, using it for a particular number of weeks, or continuing it over time produces the same outcome. The evidence also spans clinical findings, anecdotal reports, and pharmacology references, so the type of support differs substantially across the interventions.
Applicability is limited by the populations studied: health status was not specified for most interventions, while cold exposure included mixed health-status groups. The findings therefore describe reported or observed associations with memory impairment, deficits, or loss, but do not establish a single mechanism or a universal time course across interventions.
Choosing guidance
These options are not interchangeable. Some have clinical evidence from human research, while others are supported only by anecdotal reports or pharmacology references. Clinical findings still have limited reach here because the health status of participants is often not specified, and one option was studied in a mixed population. That makes it difficult to know whether the findings apply to a particular person or situation.
The time frame also matters. Evidence for some options concerns an acute exposure or a short-term effect, whereas the available information for others does not clearly establish how much was taken or how long it was used. A lack of detail about amount and duration makes direct comparison—and practical selection—more difficult.
Readers who prioritize human research should distinguish clinical evidence from anecdotal reports, which can identify experiences worth investigating but cannot show how commonly an effect occurs. Readers seeking a quick, temporary explanation should not assume that an acute finding predicts effects from longer use. The findings also use different descriptions, including memory loss, memory deficits, and memory impairment, so they should not be read as identical outcomes or as a ranked set of choices.
Because these entries concern possible causes of memory impairment rather than established ways to improve memory, they are best used to identify which options may warrant closer scrutiny, especially when the timing of symptoms corresponds with starting or using an option.