Three Habits That Seem Beneficial but Quietly Increase the Risk of Alzheimer’s Disease

Many habits considered good for health—such as eating very little fat, living overly clean, or sleeping a lot—may quietly increase the risk of Alzheimer’s disease. When taken to extremes, these seemingly correct choices can become a threat to brain health.

As the population ages rapidly, Alzheimer’s disease—also known as dementia—is becoming a fear not only for older adults but also for their families. In some respects, Alzheimer’s is even more frightening than cancer, because it gradually erases memory, personality, and the ability to care for oneself, leaving a prolonged emotional burden on loved ones. What is particularly concerning is that many studies show certain habits that appear “healthy” can quietly raise the risk of Alzheimer’s if practiced incorrectly.

According to Associate Professor Dr. Trần Văn Minh, a neurology specialist, Alzheimer’s does not appear suddenly in old age but is the result of decades of ongoing brain damage. “Daily lifestyle and dietary habits have a direct impact on brain structure, the vascular system, and neural signal transmission. If maintained incorrectly over a long period, the risk of dementia increases significantly,” he noted.

1. The first culprit: an extremely low-fat diet

For many years, eating “light” foods and consuming “little fat or oil” has been regarded as the gold standard of a healthy lifestyle. However, many people have misunderstood this concept and taken it to an extreme: following a strict vegetarian diet without control, almost completely eliminating fats, and even avoiding oil and salt altogether. In reality, the brain is an organ with a very high fat content and requires fatty acids to maintain the structure of nerve cells and the transmission of signals.

Long-term deficiency of healthy fats and high-quality protein can lead to physical weakness, pale skin, fatigue, reduced concentration, and memory decline. In older adults, malnutrition is even more dangerous, increasing the risk of osteoporosis, gallstones, and neurodegenerative diseases, including Alzheimer’s.

Experts recommend that older people maintain a balanced diet, including fish, eggs, lean meat, milk, and nuts, while increasing vegetables and fruits, rather than completely eliminating fats from meals.

2. The second culprit, paradoxically: living too clean

A large-scale study analyzing data from nearly 200 countries found that areas with high sanitation standards and strong urbanization recorded higher rates of cognitive decline and dementia. Excessive sterilization, overuse of antibacterial products, and minimal contact with nature can disrupt the body’s natural microbiome.

Growing evidence shows that the gut microbiome is closely connected to the brain through the gut–brain axis. When living environments become overly “sterile,” microbial diversity decreases, potentially disrupting the immune system and chronic inflammatory responses in the body, which in turn negatively affects brain function. This does not mean people should live unhygienically, but rather avoid extreme lifestyles and allow reasonable contact with nature, soil, plants, and outdoor environments.

3. The third culprit: sleeping too much

Everyone knows that insufficient sleep is harmful to health, but excessive sleep also carries significant risks. Many long-term studies show that adults who sleep about 6.5 to 7.5 hours per night have the lowest mortality rates and risk of chronic disease. In contrast, sleeping more than 9 hours a day—especially among older adults—is clearly associated with a higher risk of stroke and dementia.

Scientists believe that excessive sleep may be a sign that brain function has already begun to decline. In particular, if a person who previously slept normally suddenly needs much longer sleep to feel alert, accompanied by sluggishness and memory decline, this may be an early symptom of Alzheimer’s.

However, experts also emphasize that sleep needs vary from person to person. If someone consistently feels healthy and mentally sharp with longer sleep duration, there is no need for undue concern. What should raise alarm is an unusual change without a clear cause.

Alzheimer’s often begins silently with very subtle signs: frequently misplacing keys, forgetting appointments, or repeating the same sentences. Over time, patients may lose their ability to think, recognize, and care for themselves, and may even experience personality changes, becoming irritable or aggressive. This is not only a tragedy for the patient but also an emotional and financial burden for the family.

To date, the exact cause of Alzheimer’s has not been fully clarified, and there is no definitive cure. Current treatments mainly aim to slow disease progression and alleviate symptoms. Therefore, prevention plays a particularly important role.

Experts recommend building a balanced lifestyle from middle age: eat a varied and non-extreme diet; maintain physical and mental activity; sleep enough but not excessively; keep a positive mindset and social connections. Most importantly, do not let “healthy habits” go too far, because it is precisely lifestyle extremism that quietly erodes brain health over time.