You can help your brain, especially as it ages, by eating and drinking right
A two-year study which involved metabolic testing of 50 people, suggests that Alzheimer's disease consists of three distinct subtypes, each one of which may need to be treated differently. The finding may help explain why it has been so hard to find effective treatments for the disease.
The subtypes are:
More evidence for the benefits of the Mediterranean diet for fighting age-related cognitive decline comes from a large 5-year study. The study involved 960 older adults, whose cognitive change was assessed over 4.7 years. Those who followed the MIND diet more rigorously showed an equivalent of being 7.5 years younger cognitively than those who followed the diet least.
The Mediterranean-DASH Diet Intervention for Neurodegenerative Delay is a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets. It requires at least:
A study involving 264 older adults with mild cognitive impairment has found that those with normal glucose levels (167; 63%) had less cognitive decline over 2 years than those with impaired (high) glucose levels (97; 37%). They also showed less brain shrinkage and were less likely to develop Alzheimer’s. The fasting glucose levels were classified according to the American Diabetes criteria.
Data from the population-based Finnish Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE) study has revealed that healthy dietary choices in midlife may prevent dementia in later years. Out of 2,000 participants, 1,449 took part in the follow-up. The participants were 39 to 64 years old at baseline and 65 to 75 years old at follow-up.
Those who ate the healthiest diet at around age 50 had an almost 90% lower risk of dementia in a 14-year follow-up study than those whose diet was the least healthy.
Older people do seem to be much more vulnerable to deficits in thinking and remembering caused by poor diet.
Low levels of B-12 and folic acid in particular, appear to be involved in age-related cognitive decline.
Green leafy vegetables, citrus fruits and juices, whole wheat bread and dry beans are good sources of folate. Fruit and vegetables, whole grains, beans and other protein sources (nuts, meat, fish) are good sources of the B vitamins.
Experiments with rats suggest sunflower seeds (and other seeds high in linoleic acid) may help against cognitive decline caused by hypertension.
Fruits and vegetables high in antioxidants (for example, spinach, blueberries) may reduce and even reverse age-related impairment to neuron function.
Experiments in rats suggest that two chemicals normally found in the body's cells and available as dietary supplements may also improve memory function and increase energy in older people. One of these substances is found in meat and vegetables, the other in green leafy vegetables.
Carbohydrates, fat, and protein, all seem to have positive effects - different effects - on thinking and remembering. It has been shown that having breakfast has a positive effect on memory in older adults; perhaps low energy intake in general is partly responsible for cognitive decline in some older people.
Following on from the evidence that Alzheimer’s brains show higher levels of metals such as iron, copper, and zinc, a mouse study has found that amyloid plaques in Alzheimer’s-like brains with significant neurodegeneration have about 25% more copper than those with little neurodegeneration. This is consistent with a human study showing very high levels of copper in Alzheimer’s plaques.
Iron, though doubled in Alzheimer’s brains compared to controls, was not significantly different as a function of neurodegeneration, and zinc showed very little difference.
Data from the very large U.S. National Health and Nutrition Examination Survey (NHANES), involving 23,168 people, has found a significant association between low dietary fiber intake and risk of metabolic syndrome, cardiovascular inflammation, and obesity.
Dietary fiber intake was also consistently below recommended intake levels: 38g per day for men aged 19-50 years, 30g per day for men 50 and over, 25g for women aged 19-50 years, and 21g per day for women over 50. Mean dietary fiber intake was only 16.2g per day across all groups.
A study involving 12 rhesus macaques, of whom some were given access to alcohol, has found that those who drank moderately showed enhanced responses to a smallpox vaccine (compared with the control group of monkeys who drank sugar water), indicating a bolstered immune system, while heavy drinkers showed greatly diminished vaccine responses.
http://www.eurekalert.org/pub_releases/2013-12/ohs-sma121713.php
A mouse study suggests that resveratrol—a compound abundant in red wine—may moderate some of a high-fat diet’s negative effects on the immune system.
A study involving 74 older adults (70+), of whom 3 had mild dementia, 33 were cognitively normal and 38 had mild cognitive impairment, has found that high levels of "good" cholesterol and low levels of "bad" cholesterol correlated with lower levels of the amyloid-beta plaques in the brain (a hallmark of Alzheimer's disease).
http://www.eurekalert.org/pub_releases/2013-12/uoc--hga122613.php