Una gran parte del riesgo de demencia está en tus manos. El informe de 2024 de la Comisión de The Lancet vincula alrededor del 45 % de los casos de demencia a catorce factores que las personas pueden cambiar a lo largo de la vida, desde la pérdida auditiva hasta el tabaquismo. Los mismos cambios protegen el corazón. No se ha demostrado que ninguna dieta, suplemento o hábito prevenga el alzhéimer por completo. Lo que sí puedes hacer es reducir las probabilidades y, en algunos, retrasar su aparición. Eso importa, porque los primeros cambios cerebrales empiezan en la mediana edad.
Tratar la presión arterial tiene el mejor respaldo en ensayos. Corregir la pérdida auditiva es de bajo riesgo haga lo que haga por el cerebro, y mantenerse activo, bien alimentado y conectado apunta todo en la misma dirección. Los medicamentos son modestos. Las pastillas más antiguas alivian los síntomas durante un tiempo. Los nuevos anticuerpos antiamiloide ralentizan el alzhéimer temprano en una fracción de punto en la escala estándar, pero conllevan un riesgo apreciable de inflamación cerebral. Por eso llegan después de sentar las bases, decididos con un especialista.
Practice Ranking
Every practice we track for Dementia and Alzheimer's: lowering the risk, ranked by how well the evidence supports it for this condition. Strength describes the evidence, not our endorsement.
6 practices · 0 to start with
| # | Practice | Evidence | Type | Cost | Effort | Results In | Add to plan |
|---|---|---|---|---|---|---|---|
| 1 | Ginkgo Biloba: What the Big Memory Trials Actually Found Years of ginkgo did not lower the risk of developing dementia; a strong null, not a starting move. | Strong | Supplement | $ | Easy | Weeks to Months | |
| 2 | Protecting Your Hearing Treating hearing loss did not slow decline overall but slowed it about 48% in the highest-risk group; protecting and correcting hearing is a modifiable lever. | Moderate | Self-Directed | Free to $ | Easy | Longer | |
| 3 | Walking: How Many Steps You Need, and Where the Curve Flattens A two-year exercise program alone did not improve thinking in sedentary elders, but cognition improved within a multidomain diet-exercise-training program. | Moderate | Self-Directed | Free | Easy | Days to Longer | |
| 4 | The Mediterranean Diet: What It Does, Why It Works, and How to Start Top MIND-diet adherence tracked 53% less Alzheimer's in cohorts, though a 3-year randomized trial found no cognitive benefit. | Emerging | Self-Directed | $ to $$ | Moderate | Months to Longer | |
| 5 | Sleep Regularity: Why a Steady Schedule May Matter More Than Hours Six hours or less of midlife sleep tracked about 30% more dementia. | Emerging | Self-Directed | Free | Moderate | Days to Weeks | |
| 6 | Sodium Reduction & DASH Diet: What Lowers Blood Pressure, and How to Do It Blood-pressure control lowered dementia risk in the SPRINT MIND trial, which used medication, not diet, so read this as a heart-healthy-pattern signal, not a proven dietary cure. | Emerging | Self-Directed | Free to $ | Moderate | Days to Weeks | |
Default order puts the best-supported practices first, with self-directed care ahead of clinical options. Click any row to open the practice.
What It Is
Dementia is a lasting decline in memory, thinking or judgment severe enough to interfere with everyday life. It covers several diseases, each with a different cause and course, and telling them apart changes what helps.
Alzheimer's disease is the most common. Amyloid plaques and tau tangles build in the brain over years, usually starting with short-term memory and word-finding. The changes begin in midlife, long before any symptom, so what you do in your forties and fifties affects the risk decades later.
Vascular dementia comes from strokes, small-vessel disease and poor blood flow, and it often progresses in steps, with slowed thinking and trouble planning as much as memory loss. It shares its risk factors with heart disease, which makes it the most preventable of the group.
Lewy body dementia brings fluctuating attention, visual hallucinations, movement changes like Parkinson's, and vivid acting-out of dreams. It matters to recognize early, because certain antipsychotic drugs can cause severe reactions in these patients.
Mixed dementia is more than one process at once, most often Alzheimer's changes together with vascular damage. In people over 80 this combination is more common than any single pure type, part of why vascular risk factors matter even for Alzheimer's.
Mild cognitive impairment sits one step earlier: measurable memory or thinking changes greater than normal aging, with daily life still largely intact. It is a stage, and it does not always progress. Some people go on to dementia, some stay stable for years, and a meaningful number return to normal. That last outcome is most likely when a reversible cause is found and treated. It is the point at which attention pays off most.
Whatever the type, dementia tracks the health of the whole body more than the brain alone. The same process that stiffens and narrows arteries drives vascular damage in the brain. That is why vascular care ranks among the better-supported levers for the mind.
Prevention: The Risk You Can Change
The strongest lever in dementia is the risk you can change, and there is more of it than most people are told. The Lancet Commission's 2024 report estimates that about 45% of dementia cases are tied to fourteen modifiable risk factors acted on across a lifetime.
The larger contributors it models fall across three stages of life:
- Early life: less education.
- Midlife: hearing loss, high LDL cholesterol, high blood pressure, obesity, heavy drinking and head injury.
- Later life: smoking, depression, physical inactivity, diabetes, air pollution, social isolation and untreated vision loss.
Untreated vision loss and high cholesterol were added since the 2020 report. That 45% is a population estimate; it does not promise any one person a specific outcome. It assumes the links are causal and that each factor could be fully removed. The factors overlap, and 45% is the most that could ever be avoided in theory, far more than any one person can subtract from their own risk. These levers count for most in midlife, though starting later still helps.
Much of the evidence for the individual levers is observational, showing a pattern without proving cause. The people who exercise, eat well and stay connected also tend to be wealthier, better educated and healthier in ways that independently lower dementia risk. Early brain changes can also alter how people live years before a diagnosis.
Blood pressure has the strongest trial evidence behind it.
In the SPRINT MIND trial, driving systolic pressure toward 120 rather than 140 lowered the risk of mild cognitive impairment by about 19%.
The combined outcome of impairment or dementia fell by about 15%. Dementia alone fell in the same direction but did not reach statistical significance. The trial was stopped early once the heart benefit was clear, so it was left underpowered for dementia specifically.
Hearing loss is the single largest factor on the Lancet list, and correcting it is low-risk. Across the whole ACHIEVE trial, hearing aids did not slow three-year cognitive decline more than health education. In a prespecified group at higher risk, older adults with more risk factors, the same intervention slowed decline by about 48%. The overall result was null and the 48% comes from one subgroup, so it needs confirmation, but hearing aids help communication and mood in any case.
Movement, diet and sleep each point the right way, with mixed trial support.
Long cohort studies link regular activity to lower dementia risk. A two-year structured exercise program in previously sedentary older adults, the LIFE trial, did not improve thinking more than health classes. Exercise still helps mood and the blood vessels the brain depends on. It has not been shown to reverse decline once that decline has begun late in life.
A Mediterranean or MIND eating pattern was linked in a large cohort to about 53% less Alzheimer's in the closest followers. A three-year randomized trial of the MIND diet found no cognitive benefit over the control diet. The pattern is heart-safe, and its cognitive benefit is better supported by observation than by trial.
Sleeping six hours or less in midlife tracked about 30% more dementia over 25 years in the Whitehall II study. The diseases that cause dementia disturb sleep years before diagnosis, so some of that link likely runs the other way.
The clearest single signal that several levers together help comes from the Finnish FINGER trial. It combined diet counseling, exercise, cognitive training and vascular monitoring for two years. Overall cognitive scores were modestly better than with general advice. Larger and longer trials to confirm a lasting effect on dementia itself are still running.
The Research & Studies
Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.
Cognition
Los inhibidores de la colinesterasa mejoran la cognición en el Alzheimer en aproximadamente 2.4 puntos de la ADAS-Cog
Las pastillas estándar para el Alzheimer proporcionan una mejora modesta en la memoria y la función diaria durante un tiempo.
En ensayos aleatorizados, los inhibidores de la colinesterasa donepezilo, galantamina y rivastigmina mejoraron la cognición en la enfermedad de Alzheimer de leve a moderada en aproximadamente 2.4 puntos (-2.37, IC del 95 %: -2.73 a -2.02) en la escala ADAS-Cog de 70 puntos a lo largo de seis meses, con beneficios menores en la función diaria y el comportamiento. Los tres fármacos tuvieron un rendimiento similar. Measured in: Adults with mild-to-moderate Alzheimer's disease across pooled randomized, placebo-controlled trials. El beneficio es sintomático y no ralentiza la enfermedad subyacente, y efectos secundarios como náuseas, diarrea, ritmo cardíaco lento y pérdida de apetito son lo bastante comunes como para que algunas personas dejen el fármaco.
The study · 1
Birks, Cholinesterase inhibitors for Alzheimer's disease (Cochrane review) · Cochrane Database Syst Rev 2006;(1):CD005593
El lecanemab ralentizó el deterioro en aproximadamente un 27 % a lo largo de 18 meses, con hinchazón cerebral en el 12.6 %
El lecanemab ralentizó el deterioro en aproximadamente un cuarto a lo largo de 18 meses en el Alzheimer temprano, con hinchazón cerebral en aproximadamente una de cada ocho personas.
En 1795 personas con enfermedad de Alzheimer temprana, el lecanemab ralentizó el deterioro en la escala CDR-SB en un 27 % a lo largo de 18 meses, una diferencia ajustada de 0.45 puntos (1.21 frente a 1.66), a la vez que eliminaba la amiloide del cerebro. La hinchazón cerebral (ARIA-E) se produjo en el 12.6 % frente al 1.7 % con placebo, las microhemorragias y el sangrado superficial (ARIA-H) en el 17.3 %, y las reacciones a la infusión en aproximadamente el 26 %. Measured in: 1795 adults aged 50 to 90 with early Alzheimer's disease and confirmed amyloid in the Clarity AD trial. La diferencia absoluta es pequeña y su significado en la vida cotidiana se debate. El fármaco requiere amiloide confirmada, infusiones dos veces al mes y monitorización repetida con resonancia magnética, y la hinchazón cerebral y el sangrado pueden ser graves, más aún en portadores de dos copias del gen APOE4.
The study · 1
van Dyck et al., Lecanemab in early Alzheimer's disease (Clarity AD) · N Engl J Med 2023;388(1):9-21
El donanemab ralentizó el deterioro entre aproximadamente un 22 % y un 35 % a lo largo de 18 meses, con hinchazón cerebral en aproximadamente el 24 %
El donanemab ralentizó el deterioro entre aproximadamente un quinto y un tercio a lo largo de 18 meses, con hinchazón cerebral en aproximadamente una cuarta parte de las personas.
En 1736 personas con enfermedad de Alzheimer temprana y sintomática, el donanemab ralentizó el deterioro a lo largo de 18 meses en aproximadamente un 35 % en una escala combinada de la enfermedad en quienes tenían tau de bajo a medio, y en aproximadamente un 22 % en todo el grupo, a la vez que eliminaba la amiloide. La hinchazón cerebral (ARIA-E) se produjo en aproximadamente el 24 %, con casos graves en una pequeña minoría, y se vincularon tres muertes al fármaco. Measured in: 1736 adults aged 60 to 85 with early symptomatic Alzheimer's disease and confirmed amyloid and tau in TRAILBLAZER-ALZ 2. Como con el lecanemab, el beneficio absoluto es modesto y se debate, y el riesgo de hinchazón cerebral y sangrado, incluidas muertes poco frecuentes, significa que se usa solo en la enfermedad confirmada en fase temprana con monitorización por resonancia magnética.
The study · 1
Sims et al., Donanemab in early symptomatic Alzheimer disease: the TRAILBLAZER-ALZ 2 randomized clinical trial · JAMA 2023;330(6):512-527
Años de ginkgo no redujeron el riesgo de desarrollar demencia
Tomar ginkgo durante años no redujo la probabilidad de desarrollar demencia en un gran ensayo con adultos mayores.
En el ensayo GEM, 3069 adultos de 75 años o más tomaron ginkgo biloba a 120 mg dos veces al día o placebo durante una mediana de aproximadamente seis años. El ginkgo no redujo la incidencia de demencia por cualquier causa ni de la enfermedad de Alzheimer (cociente de riesgo de 1.12 para la demencia, IC del 95 %: 0.94 a 1.33). Measured in: 3069 community-dwelling adults aged 75 and over, with normal cognition or mild cognitive impairment at entry. Esto evaluó la prevención en personas que ya tenían 75 años o más y no aborda su uso en etapas anteriores de la vida, pero es el mayor ensayo de prevención con ginkgo y el resultado fue claramente nulo.
The study · 1
DeKosky et al., Ginkgo biloba for prevention of dementia: a randomized controlled trial (GEM Study) · JAMA 2008;300(19):2253-2262
Aproximadamente el 45 % del riesgo de demencia está vinculado a catorce factores sobre los que se puede actuar
A 2024 expert commission estimated that about 45% of dementia cases are linked to fourteen risk factors people can act on, such as hearing loss, high blood pressure and inactivity.
La Comisión Lancet de 2024 atribuye alrededor del 45 % de los casos de demencia a catorce factores de riesgo modificables abordados a lo largo de la vida. Los mayores contribuyentes que modela son menos educación en la vida temprana, pérdida auditiva y colesterol LDL alto en la mediana edad, y aislamiento social en la vida posterior, con la hipertensión, la obesidad, el tabaquismo, la depresión, la inactividad física, la diabetes, el consumo excesivo de alcohol, el traumatismo craneoencefálico, la contaminación del aire y la pérdida de visión no tratada componiendo el resto. La pérdida de visión no tratada y el colesterol LDL alto se añadieron desde el informe de 2020. Measured in: A commission synthesis of cohort and trial evidence estimating population-attributable fractions for dementia worldwide. Se trata de una estimación de riesgo atribuible poblacional que asume que las asociaciones son causales y que cada factor podría eliminarse por completo, y los factores se solapan, por lo que es un techo de lo teóricamente evitable, no una promesa para ninguna persona en particular.
The study · 1
Livingston et al., Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission · Lancet 2024;404(10452):572-628
El control intensivo de la presión arterial redujo el deterioro cognitivo leve en aproximadamente un 19 %
Reducir la presión arterial de forma más agresiva disminuyó el riesgo de deterioro cognitivo leve en aproximadamente un 19 %, casi una quinta parte; la caída en la demencia en sí fue en la misma dirección, pero no estadísticamente cierta.
Aleatorizar a adultos de 50 años o más con hipertensión a un objetivo sistólico por debajo de 120 en lugar de por debajo de 140 redujo el deterioro cognitivo leve (cociente de riesgo 0.81, IC del 95 %: 0.69 a 0.95) y el resultado combinado de deterioro cognitivo leve o demencia probable (0.85, 0.74 a 0.97). La demencia probable por sí sola fue menor en la misma dirección, pero no alcanzó significación (0.83, 0.67 a 1.04). Measured in: 9361 adults aged 50 and over with hypertension and raised cardiovascular risk in the SPRINT MIND trial. El ensayo se detuvo antes de tiempo una vez que el beneficio cardiovascular quedó claro, lo que lo dejó con potencia estadística insuficiente específicamente para la demencia, y el objetivo intensivo requiere más medicamentos y un seguimiento más estrecho.
The study · 1
Williamson et al., Effect of intensive vs standard blood pressure control on probable dementia: a randomized clinical trial (SPRINT MIND) · JAMA 2019;321(6):553-561
Los audífonos no ralentizaron el declive en general, pero lo ralentizaron en aproximadamente un 48 % en el grupo de mayor riesgo
Los audífonos no ralentizaron el declive del pensamiento en general, pero en el grupo de mayor riesgo lo ralentizaron en aproximadamente la mitad.
A lo largo de tres años, los audífonos con apoyo audiológico no ralentizaron el declive cognitivo global más que un control de educación sanitaria en todo el ensayo ACHIEVE (diferencia entre grupos cercana a cero). En un grupo preespecificado de mayor riesgo, adultos mayores reclutados de una cohorte cardiovascular existente con más factores de riesgo, la misma intervención ralentizó el declive cognitivo en aproximadamente un 48 %. Measured in: 977 adults aged 70 to 84 with untreated mild-to-moderate hearing loss in the ACHIEVE randomized trial. El resultado general fue nulo, y la cifra del 48 % proviene de un único subgrupo preespecificado, no de todo el ensayo, por lo que necesita confirmación. Corregir la audición conlleva beneficios claros para la comunicación y el estado de ánimo en cualquier caso.
The study · 1
Lin et al., Hearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE) · Lancet 2023;402(10404):786-797
Un programa de dos años de dieta, ejercicio y entrenamiento cerebral mejoró modestamente la cognición (FINGER)
Trabajar la dieta, el ejercicio, el entrenamiento cerebral y la salud cardíaca juntos durante dos años llevó a puntuaciones de pensamiento modestamente mejores que el consejo general.
Un programa de dos años que combinaba asesoramiento dietético, ejercicio, entrenamiento cognitivo y seguimiento del riesgo vascular produjo mejores puntuaciones generales en las pruebas cognitivas que el consejo de salud general, una diferencia entre grupos de aproximadamente 0.02 al año en un compuesto estandarizado favorable al programa, con ganancias más claras en la función ejecutiva y la velocidad de procesamiento. Measured in: 1260 adults aged 60 to 77 at raised risk of dementia in the Finnish FINGER trial. Las ganancias fueron modestas y se midieron en pruebas cognitivas, no en diagnósticos de demencia, y todavía se están realizando ensayos más grandes y largos para confirmar un efecto duradero sobre la demencia en sí.
The study · 1
Ngandu et al., A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER) · Lancet 2015;385(9984):2255-2263
Un programa de ejercicio de dos años no mejoró el pensamiento general en adultos mayores sedentarios
Un programa de ejercicio de dos años no mejoró el pensamiento general más que las clases de salud en adultos mayores previamente inactivos.
Un programa estructurado de actividad física de 24 meses no mejoró la cognición global en comparación con un control de educación sanitaria en adultos mayores sedentarios. Hubo un indicio de mejor función ejecutiva entre quienes tenían 80 años o más y quienes tenían una función basal más baja, pero el criterio de valoración cognitivo principal no mostró diferencia general. Measured in: 1635 sedentary adults aged 70 to 89 in the LIFE randomized trial. Esto evaluó el ejercicio comenzado tarde en la vida para un criterio de valoración cognitivo y no informa sobre una vida entera de actividad; los participantes ya estaban en riesgo de problemas de movilidad. La actividad sigue beneficiando al corazón, al estado de ánimo y a la vía vascular que llega a la demencia.
The study · 1
Sink et al., Effect of a 24-month physical activity intervention vs health education on cognitive outcomes in sedentary older adults: the LIFE randomized trial · JAMA 2015;314(8):781-790
Un ensayo de tres años sobre la dieta MIND no encontró un beneficio cognitivo frente al control
En un ensayo de tres años, seguir la dieta MIND no mejoró el pensamiento más que la dieta de comparación.
Aleatorizar a 604 adultos mayores con antecedentes familiares de demencia a la dieta MIND o a una dieta control, ambas con una restricción calórica leve, no produjo una diferencia significativa en el cambio cognitivo ni en las medidas de resonancia magnética cerebral a lo largo de tres años. Ambos grupos mejoraron ligeramente en el compuesto cognitivo. Measured in: 604 adults aged 65 and over, overweight with a suboptimal diet and a family history of dementia. Ambos grupos redujeron las calorías y perdieron peso, lo que podría haber reducido cualquier diferencia, y tres años podrían ser un período demasiado corto para revelar un efecto sobre una enfermedad que se desarrolla a lo largo de décadas.
The study · 1
Barnes et al., Trial of the MIND diet for prevention of cognitive decline in older persons · N Engl J Med 2023;389(7):602-611
La adherencia más alta a la dieta MIND se asoció con un 53 % menos de Alzheimer en una cohorte
Las personas que seguían más de cerca la dieta MIND desarrollaron Alzheimer aproximadamente la mitad de veces que las que la seguían menos.
En una cohorte prospectiva de 923 adultos mayores seguidos durante aproximadamente 4.5 años, quienes estaban en el tercio superior de adherencia a la dieta MIND tuvieron una tasa de enfermedad de Alzheimer un 53 % más baja que el tercio inferior (cociente de riesgo 0.47, IC del 95 %: 0.26 a 0.76), e incluso la adherencia del tercio medio conllevó una tasa un 35 % más baja. Measured in: 923 adults aged 58 to 98 in the Rush Memory and Aging Project. What could explain it instead: People who eat this way tend to be more educated, more physically active and higher income, and to have less vascular disease, all independently linked to lower dementia risk; early cognitive change can also alter how people eat, running the association the other way.. Esto es observacional y no puede demostrar causalidad; la estimación del efecto proviene de patrones alimentarios autoinformados en una única ventana temporal.
The study · 1
Morris et al., MIND diet associated with reduced incidence of Alzheimer's disease · Alzheimers Dement 2015;11(9):1007-1014
Sleep
Seis horas o menos de sueño en la mediana edad se asociaron con aproximadamente un 30 % más de demencia
Las personas que dormían habitualmente seis horas o menos en la mediana edad tenían aproximadamente un 30 % más de probabilidades de desarrollar demencia que quienes dormían siete horas.
En la cohorte Whitehall II de 7959 adultos seguidos hasta 25 años, un sueño corto persistente de seis horas o menos entre los 50 y los 70 años se asoció con un riesgo de demencia aproximadamente un 30 % más alto que un sueño de siete horas (cociente de riesgo 1.30, IC del 95 %: 1.00 a 1.69). El sueño corto medido a los 50 años y a los 60 años mostró la misma dirección. Measured in: 7959 British civil servants in the Whitehall II study, followed a median of about 25 years with 521 dementia cases. What could explain it instead: The diseases that cause dementia disrupt sleep years before diagnosis, so short sleep in midlife may be an early sign of the process, not a cause of it; depression and other conditions affect both sleep and dementia risk as well.. Esto es observacional, por lo que muestra asociación en lugar de causa, y el intervalo de confianza llega al borde de la ausencia de efecto.
The study · 1
Sabia et al., Association of sleep duration in middle and old age with incidence of dementia · Nat Commun 2021;12(1):2289
What To Do First
Most of this is free or cheap. Pick a few you can hold steadily; you do not need to do all at once.
Hearing loss tops the Lancet list, and treating it carries little downside whatever it does for memory. A hearing test is often free, and over-the-counter aids have made this far cheaper than it used to be.
Blood pressure is the best-tested dementia lever. A home monitor costs little. If the average runs high, that is the case to take to a clinician, and it is your strongest single move.
Regular activity is linked to lower risk and helps mood, sleep and the blood vessels the brain depends on. Walking is free and counts; adding some resistance work protects the muscle and the metabolism that go with a healthy brain.
Build meals on vegetables, beans, whole grains, olive oil, fish and berries, and cut ultra-processed food and sugary drinks. Canned fish, frozen vegetables and dried beans make this cheap, and the pattern is good for the whole body whether or not it moves the cognitive numbers.
Aim for a steady seven hours or so. Loud snoring, gasping or witnessed pauses in breathing are worth getting looked at, since treating sleep apnea helps blood pressure, mood and daytime thinking.
Social contact, purpose and demanding new learning are all linked to lower risk. A standing meet-up, a language, an instrument or a craft asks more of the brain, and it costs nothing but time.
Before accepting a dementia label, several reversible causes are worth checking, because any of them can mimic or worsen the picture. Vitamin B12 and thyroid can be ordered through direct-to-consumer testing as well as through a clinician.
Where the Medicines Fit
No drug yet halts the underlying disease or turns it back. Cholinesterase inhibitors, the drugs donepezil, galantamine and rivastigmine, give a modest improvement in memory and daily function for a time. Across randomized trials they lifted cognition by about 2.4 points on the 70-point ADAS-Cog scale over six months, with smaller gains in daily function and behavior. The three perform similarly. They ease symptoms; they do not slow the underlying disease, and the benefit lasts only while the drug is taken. Nausea, diarrhea, a slow heart rate and appetite loss are common enough that some people stop.
For moderate-to-severe disease, memantine is sometimes added, again for a modest symptomatic effect. In Lewy body dementia the cholinesterase inhibitors can help attention and hallucinations specifically.
The anti-amyloid antibodies are the newest and the most debated. Both clear amyloid from the brain, and both modestly slow early Alzheimer's disease. Lecanemab slowed decline on the CDR-SB scale by 27% over 18 months in early disease, a difference of 0.45 points on an 18-point scale (1.21 against 1.66 on placebo). Donanemab slowed decline by about 35% in people with lower tau and about 22% across the whole group on a combined disease scale over the same period.
The safety concern is serious. Brain swelling, called ARIA, occurred in 12.6% of people on lecanemab and about 24% on donanemab. Small bleeds are common alongside it. Most cases cause no symptoms and show up only on a scan, though some are serious; donanemab's trial recorded three deaths linked to the drug. The risk is higher in people carrying two copies of the APOE4 gene. The antibodies are used only in early, confirmed Alzheimer's, with genetic testing and repeated MRI scans. The decision is made with a specialist who weighs a fraction of a point of slowing against the swelling and bleeding risk. Whether the benefit is large enough to be worth it in daily life is contested.
Much of living well with dementia is not about drugs. Treating pain, constipation, poor sleep and infection often settles agitation better than any sedative. Routine, orientation, music and familiar company help.
What Does Not Help, and What to Rule Out First
A large industry sells prevention that the evidence does not support. Ginkgo biloba is the clearest example. A trial gave it to more than 3,000 adults aged 75 and over for about six years. It did not lower the rate of dementia or Alzheimer's at all. Coconut oil, most nootropics and the supplements marketed for brain health have no trial evidence for preventing Alzheimer's or slowing its course. A few carry their own risks.
Brain-training apps improve the game itself and very similar tasks, with little measured carryover to everyday thinking. Demanding, varied learning (a language, an instrument, a craft) asks more of the brain.
One step comes first when thinking changes: rule out the causes that are reversible. Low vitamin B12, an underactive thyroid, depression, sleep apnea, heavy alcohol use and certain medications can all mimic or worsen dementia. Normal-pressure hydrocephalus is a treatable build-up of fluid around the brain. It brings a triad of unsteady walking, incontinence and cognitive slowing, and can improve with treatment. A slow change in thinking calls for a doctor's visit and a thorough first workup before any dementia diagnosis is accepted.
Go Deeper
- High blood pressure: how to measure it right and what lowers it, the best-supported dementia lever and a heart protector in its own right.
- Hearing protection: guarding the hearing whose loss is the single largest modifiable risk factor.
- Neuroplasticity: the adult brain's capacity to form new connections through demanding learning, exercise and sleep, including the year of walking that regrew the memory hippocampus about 2%.
- Mediterranean diet: the eating pattern behind the diet findings here, plate by plate.
- Type 2 diabetes: the metabolic and vascular pathway that reaches the brain, and how to change it.
- Insulin and glucose: the biology linking blood sugar, blood vessels and cognition.
The Chinese Medicine View
The Chinese Medicine View
Chinese medicine has no category that maps onto Alzheimer's or a scan showing amyloid; it reads the person. The classical frame for failing memory is Dai (呆), dullness, tied above all to the Kidney, said to rule the bones and generate marrow. The brain is named the Sea of Marrow. When the Kidney essence that fills that sea declines with age, the tradition expects memory, hearing and the bones to weaken together. The Heart is held to house the Shen, the spirit and mental clarity, so classical thinking looks at the Heart and Kidney as much as the head itself. Sudden confusion is treated as a separate, urgent picture entirely.
Slow forgetfulness with age alongside low back and knee weakness, hearing decline, night-time urination and a fatigue that rest does not fully mend, with a pale or thin tongue. The direction is to tonify the Kidney and nourish essence and marrow, distinguishing a colder Yang-deficient picture from a drier Yin-deficient one.
A muddled, foggy quality, heaviness, a thick greasy tongue coat, sometimes emotional dullness or apathy more than pure memory loss. The direction is to transform Phlegm and open the orifices; rich, cloying tonics thicken the obstruction.
Poor memory with palpitations, anxiety, poor sleep, low appetite and tiredness, with a pale complexion. The Spleen builds the blood that nourishes the Shen, so the direction is to strengthen both Heart and Spleen until the mind is settled and fed.
Cautions and Interactions
Extra restraintEverything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.
Anticholinergic medicines dull thinking
A long list of common drugs, some for bladder control, allergies, sleep and older depression, carry an anticholinergic effect that clouds thinking. Heavy use over years is linked to higher dementia risk. If thinking is a concern, ask a prescriber or pharmacist to review the whole list; many have gentler alternatives.
Antipsychotics can be dangerous in Lewy body dementia
People with Lewy body dementia can have severe, sometimes life-threatening reactions to certain antipsychotic drugs, so a diagnosis matters before any is used for hallucinations or agitation. In dementia generally, antipsychotics raise the risk of stroke and death, so they are reserved for serious distress.
Anti-amyloid antibodies need genotyping and MRI monitoring
Lecanemab and donanemab can cause ARIA, meaning brain swelling or small bleeds. The risk is higher with two APOE4 copies, so genotyping and repeat MRI are part of the decision. Blood thinners add to it. New headache, confusion, vision change or weakness during treatment means contacting the treating team the same day.
Ginkgo and blood thinners
Ginkgo has a mild blood-thinning effect and can add to bleeding risk alongside anticoagulants, antiplatelet drugs or before surgery.
Most of lowering your risk is yours to do and low-harm. Where a medicine or monitored treatment is involved, that decision is shared with a clinician. If thinking changes, ruling out the reversible causes comes first.
When to See Someone
Most of lowering dementia risk is steady, long-term work on blood pressure, hearing, movement and sleep. A few situations are different and need a doctor now. These are the signs to get seen about:
- Confusion that comes on suddenly, over hours or a few days, or a sharp change in alertness. This can be delirium from infection, medication, dehydration or a metabolic problem, and it needs same-day assessment(seek urgent care)
- A step-change decline in thinking over weeks, or new weakness, numbness, trouble speaking or a facial droop. This can mean a stroke or another treatable cause, and it needs prompt care(seek urgent care)
- A first, thorough workup for reversible contributors before a dementia label is accepted, covering thyroid, B12, medications, sleep apnea and the like, any of which can mimic or worsen the picture
- New headache with confusion, unsteadiness or falls in someone on blood thinners or after a head injury. This can point to bleeding around the brain(seek urgent care)
- New or worsening headache, confusion, vision change or weakness in someone on an anti-amyloid antibody. This can signal the brain swelling these drugs cause; contact the treating team urgently(seek urgent care)
- Safety concerns already here: getting lost while driving, leaving the stove on, wandering, or trouble managing medications, all worth raising early, before a crisis
- Hallucinations, marked day-to-day fluctuation in alertness, or acting out dreams. These point toward Lewy body dementia and change what drugs are safe, so a diagnosis matters before any antipsychotic is used
- Strain, low mood or exhaustion in whoever provides the daily care, common, and a reason to arrange support and respite early
At any worrying change, the first step is a workup for the treatable causes: thyroid, B12, medications, sleep apnea. That is where a doctor comes in.
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All 12 sources on this page independently checked and cross-referenced.
Thomas Dehli, Founder & Editor, Sacred Lotus
Sacred Lotus has published Chinese medicine reference material since 2001. Integrative pages are held to the same standard as the herb and formula library: cite the source, grade the claim at its real strength, and say where the research has not looked. This page is educational and it is not medical advice. Last reviewed and updated August 9, 2026.
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