Share on Pinterest Research has shown that there is a two-way link between diet and Alzheimer's disease. Sergei Narevskih/Stocksy
- Malnutrition can trigger the onset of Alzheimer's disease, and the progression of the disease then increases malnutrition, according to a new study from China.
- The hope is that better addressing people's nutritional needs will reduce the incidence of Alzheimer's disease and other forms of dementia.
- The study examined two diets: the Mediterranean diet and the MIND diet.
A new study from China examines the complicated, perhaps bidirectional, relationship between Alzheimer's disease (AD) and malnutrition.
The study concluded that early identification and dietary intervention of people who are at nutritional risk or malnourished can reduce their chances of developing Alzheimer's disease.Once Alzheimer's disease sets in, people often experience increasing levels of malnutrition as the disease enters a downward spiral as adequate nutrition becomes increasingly difficult to maintain.
As the world's population ages, the number of new cases of age-related dementia has declined in many countries, the report said The 2020 Lancet Commission report. The report notes that improvements in nutrition, education, healthcare and lifestyle are driving this trend.
The Commission estimated that 12 modifiable factors are responsible for 40% of dementias worldwide.These include "less education, high blood pressure, hearing loss, smoking, obesity, depression, physical inactivity, diabetes and little social contact." The good news is that these are controllable factors.
Previous research suggests that in people with mild cognitive impairment (MCI), a significant reduction in body mass index (BMI) may be an early indicator of cognitive decline. Another study found that at each stage of Alzheimer's disease, malnutrition becomes more apparent, as evidenced by lower weight, lower BMI and lower lean fat mass, and higher fat mass.
The new observational study involved 266 people in China. Of these, 73 people from the general population were assessed as cognitively healthy. The rest of the participants were enrolled at the Center for Cognitive Neurology at Beijing Tiantan Hospital. Of these people, 72 had mild cognitive impairment due to Alzheimer's disease (AD-MCI), and 121 people had dementia due to Alzheimer's disease (AD-D).
The researchers took venous blood samples from the participants and took detailed body measurements.
The research was published in Limits in nutrition.
Researchers ranked the quality of study participants' diets based on their adherence to the Mediterranean (MED) diet and the MIND diet (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay). Overall, there was no statistically significant difference in diet scores between the three groups. However, scores were slightly lower for people with AD-Dthan AD-MCI and normal cognition groups.
The study does not report the specific foods that earned participants their rankings.
Neuroscientist Dr. Scott Kaiser, who was not involved in the study, asked whether the participants earned their scores "on green leafy vegetables, or did they get their points on nuts, or did they get them on olive oil, or did they get them on fish - and what kind of fish ?" These, he said, "would all make a big difference."
"Nutritional studies are very difficult to conduct and there is a clear need for more randomized, prospective studies," he added.
Lower BMI, smaller calf and hip circumferences, and lower Mini Nutritional Assessment and Geriatric Nutritional Risk Index scores were associated with Alzheimer's disease, as were lower levels of total protein, albumin, globulin, and apolipoprotein A1.
The most accurate predictor of Alzheimer's disease was a combination of total protein and albumin levels, combined with calf circumference.The MNA score was the clearest indicator of the boundary between mild Alzheimer's cognitive impairment (AD-MCI) and full-blown Alzheimer's dementia (AD-D).
Although not discussed in this study, Dr. Kaiser points out that "a fascinating area of research is the impact of an altered microbiome and how this could influence nutrient absorption and energy balance and factors that influence brain health."
People with Alzheimer's disease often become increasingly malnourished as the disease progresses. It may be that Alzheimer's disease causes this, or it may simply be that malnutrition - perhaps a factor in the initial development of the disease - only makes matters worse over time.
According to Dr. Kaiser, there may be both biological and social mechanisms underlying the greater prevalence of malnutrition in Alzheimer's disease.
Michelle Routhenstein, registered dietitian and nutritionist at EntirelyNourished.com noted, "Individuals with Alzheimer's disease are more likely to suffer from malnutrition due to challenges such as difficulty chewing and swallowing, altered taste and smell perception, forgetting to eat, difficulty meal preparation and behavioral symptoms such as agitation or lack of interest in food that affect eating habits and nutritional intake.
Referring to the social barriers, Dr. Kaiser: "If someone cannot feed themselves, if they are dependent on someone else for nutrition, and if their mechanism to indicate hunger does not work properly, then you have a problem. problem.
The MED and MIND diets are related because they are both based on the traditional way of eating in areas around the Mediterranean. Both benefit cardiovascular health and weight loss when combined with a physically active lifestyle and social engagement.
Both the MED and MIND diets have also been linked to cognitive health.The MED diet emphasizes plant foods such as vegetables, fruits, legumes and whole grains, eaten with meals and as snacks. Additionally, the diet calls for healthy fats such as extra-virgin olive oil, as well as moderate consumption of fish, smaller amounts of meat or eggs, and a general avoidance of processed foods.
The MIND diet is based on the Med diet and the DASH diet (Dietary Approaches to Stop Hypertension). It focuses specifically on supporting cognitive health.
The diet calls for six or more servings per week of: "Leafy greens, leafy greens, leafy greens, for starters," said Dr. Kaiser.In addition, according to Routhenstein, the diet recommends "berries, nuts, legumes, whole grains, fish, poultry and olive oil, while avoiding red meat, butter and margarine, cheese, pastries and fried or fast foods."
Routhenstein mentioned some specific foods that boost cognitive reserves in people who want to avoid dementia or Alzheimer's disease-related dementia.
"Blueberries, strawberries and other berries contain antioxidants and flavonoids that may help improve memory and cognitive function," she said. Dr. Kaiser praised the value of colorful fruits and vegetables.Additionally, Routhenstein said, "Sesame seeds and flaxseeds are rich in healthy fats. Polyphenic compounds, such as lignans, support brain health and may help reduce the risk of cognitive decline."
The MIND diet calls for three or more servings of whole grains per day, such as, she said, "oats, barley and quinoa." [that] provide a constant supply of energy to the brain and contain nutrients such as vitamin B6 and folic acid, which support cognitive function."
Dr. Kaiser emphasized the value of fish in the MIND diet, especially "fish that are high in these omega-3 fatty acids, specifically DHA, and found in cold-water oily fish. Salmon is a good example."
Routhenstein cautioned, "It is important to note that these diets must be well balanced and implemented appropriately to also address potential muscle loss and tone, which can influence the progression of Alzheimer's disease."She recommended consulting a registered dietitian nutritionist to create a nutrition plan that is well suited for each person.
