Non-Pharmacological Interventions for Alzheimer's Disease: A Comprehensive Approach to Prevention and Care

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that poses an enormous burden on individuals, families, and healthcare systems worldwide. While pharmacological treatments remain limited in their ability to halt or reverse the disease, growing evidence suggests that non-pharmacological interventions play a critical role—particularly in primary and secondary prevention. These interventions, which encompass lifestyle modifications, cognitive engagement, social participation, and neuromodulation, offer a practical and accessible avenue for reducing risk and slowing cognitive decline. Among them, the comprehensive model of "diet, sleep, exercise, engagement, thinking, social interaction, and regulation" has gained increasing attention. The following sections elaborate on each of these dimensions.

1. Diet: Healthy Dietary Patterns

Some scholars have found that healthy dietary patterns are considered the most important protective factor for preventing cognitive decline and dementia onset [1].

Currently, the most internationally accepted healthy diets are the Mediterranean Diet (MD) and the Dietary Approaches to Stop Hypertension (DASH).

(1) The Mediterranean Diet has been strongly recommended in recent years. Its dietary composition can be simply divided into: 1) Fish: at least 6 meals/week; 2) Fruits: 3–4 servings/day; 3) Vegetables: 3–4 servings/day; 4) Legumes, olive oil, nuts, cheese, poultry, and grains can be consumed regularly.

In a study on the Mediterranean Diet, individuals with vascular risk factors were randomly assigned to two different dietary therapies: one was the Mediterranean Diet, and the other was a low-fat diet with controlled fat intake. After six and a half years of dietary therapy, those who adhered to the Mediterranean Diet scored significantly higher on cognitive tests (mainly the MMSE and Clock Drawing Test) than those on the low-fat diet [2], suggesting that the Mediterranean Diet has a certain cognitive protective effect.

(2) The DASH Diet primarily consists of: 1) Fruits: 4–5 servings/day; 2) Vegetables: 4–5 servings/day; 3) Grains: 6–8 servings/day; 4) Dairy: 2–3 servings/day; 5) Fish, poultry, or lean meat: no more than 6 servings/day; 6) Nuts or legumes: 4–5 servings/week; 7) Fats and oils: 2–3 servings/day; 8) Sugar: no more than 5 servings/week; 9) Sodium: no more than 2300 mg/day. Its main advantage is its blood pressure-lowering effect, and it is also suitable for patients with diabetes.

One study showed that 124 obese patients with hypertension were randomly assigned to three groups: a DASH diet group, a DASH diet combined with exercise and calorie restriction group, and a normal diet control group. After 4 months of dietary intervention, patients on the DASH diet completed neuropsychological scale tests much more efficiently than the normal diet control group [3], indicating that the DASH diet also protects the brain while lowering blood pressure.

Recently, scientists designed a dietary approach combining the Mediterranean Diet and the DASH Diet, called the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND). It combines the advantages of the Mediterranean Diet and the DASH Diet and emphasizes dietary components with neuroprotective and dementia-preventing effects.

Research has shown that adhering to the MIND diet for several years can delay age-related cognitive decline[4]. Meanwhile, another prospective study by the same team showed that adherence to the MIND healthy diet can reduce the risk of AD onset and progression[5].

Like the characteristics of the Mediterranean Diet and the DASH Diet, the MIND diet is based on natural grains and limits the intake of animal fats and saturated fatty acids, but uniquely increases the intake of berries and leafy greens, without emphasizing large amounts of fruits (the DASH diet recommends 3–4 servings daily), potatoes, dairy, and fish. This is because studies have found that increasing fresh vegetable intake by two or more servings per day can effectively slow cognitive decline, and if six servings of leafy green vegetables can be added per week, the protective effect is even more significant[6]. Another study showed that the intake of blueberries or strawberries is closely related to delaying cognitive decline[7]. Therefore, the MIND diet has adjusted its food composition in these aspects compared with the Mediterranean Diet and the DASH Diet. The MIND diet does not emphasize a large amount of fish intake per week like the Mediterranean Diet, but instead recommends one fish meal per week. It also does not emphasize low salt and low fat like the DASH Diet, because it was found that these were not correlated with brain protection.

(3) The current MIND diet structure can basically be summarized as: 1) Fish: 1 meal/week; 2) Legumes: 1 serving every other day; 3) Poultry: 2 servings/week; 4) Berries: 2 servings/week; 5) Nuts: moderate amount/week; 6) Fruits and vegetables: moderate amount/day; 7) Grains: 3 servings/day; 8) Red wine: 1 small glass/day.

The MIND diet recommends "ten brain-healthy foods," including leafy green vegetables, other vegetables, nuts, berries, legumes, grains, fish, poultry, olive oil, and red wine. It also identifies five "unhealthy brain foods": red meat, butter and margarine, sweets, fried foods, and junk food. As a protective factor that can be mastered through one's own efforts, healthy dietary patterns are being widely accepted by the public. A healthy diet is also a good lifestyle habit that needs to be developed and maintained over the long term to see results.

2. Exercise: Physical Exercise and Physical Activity

Persistent regular physical exercise, combining aerobic exercise, strength training, and flexibility training, not only benefits cardiovascular and cerebrovascular health but also protects cognitive function through mechanisms such as improving cerebral blood flow and promoting the release of neurotrophic factors.

3. Engagement: Cognitive Training and Mental Activities

Actively participating in cognitive stimulation activities such as reading, writing, learning new skills, playing chess, and doing puzzles helps build and maintain "cognitive reserve" and delay cognitive decline.

4. Thinking: Mindfulness, Thought Regulation, and Psychological Growth

Cultivating mindfulness meditation habits, maintaining positive thinking and a lifelong learning attitude, and engaging in thought regulation and psychological growth training all have positive effects on relieving stress and improving mood and cognition.

5. Sleep: Ensuring "Brain Waste Clearance Time"

Sleep is a critical period for the brain to clear metabolic waste (including β-amyloid). It is recommended to maintain sleep duration at 6.5–7.4 hours and follow the golden rules: fall asleep before 22:30 and avoid using mobile phones 2 hours before bedtime to prevent blue light from inhibiting melatonin secretion. Techniques for improving sleep include meditating for 10 minutes before bedtime, keeping the bedroom dark (light intensity < 300 Lux), and stopping caffeine intake in the afternoon.

6. Social Interaction: Social Engagement

Social interaction is an important protective factor for maintaining cognitive function. Actively participating in social activities, maintaining good interpersonal interactions, joining interest clubs, participating in volunteer services, or regularly gathering and communicating with relatives and friends can effectively reduce loneliness and lower the risk of cognitive decline. Especially in older age, a rich social network helps enhance psychological resilience and has an irreplaceable protective effect on brain health.

7. Regulation: Psychological Regulation and Neuromodulation

(1) Psychological regulation: This includes emotional counseling, stress management, psychological counseling, and cognitive behavioral intervention, helping individuals maintain psychological resilience and emotional stability.

(2) Neuromodulation: In recent years, non-invasive neuromodulation technologies have brought new hope for AD intervention. 

(3) Multimodal therapy: In addition, the following non-pharmacological intervention methods are also worth trying. They need to be individualized and require persistence to be effective:

Light therapy: regulates circadian rhythms and improves sleep and mood through light of specific wavelengths and intensities.

Music therapy: uses the rhythm and melody of music to activate neural pathways, improve mood, evoke memories, and reduce anxiety.

Dance therapy: combines physical movement with musical rhythm, simultaneously exercising coordination and cognitive function, and improving balance and social ability.

In summary, after symptoms appear, seek medical attention promptly and go to a neurology specialist clinic with a memory clinic. After a comprehensive examination, follow the doctor's advice for treatment and do not slack off. Because AD is a chronic disease, it requires family members to take it seriously and have great patience. Long-term care of patients will exhaust the caregiver physically and mentally. Therefore, from the beginning, a long-term diagnosis, treatment, and care plan should be formulated according to the family's financial situation. Do not rely on a momentary effort and give up halfway.