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    Age-Related Cognitive Decline (Holistic)

    Age-Related Cognitive Decline (Holistic)

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    About This Condition

    With a little help you can reduce the effects of ARCD, such as memory problems. According to research or other evidence, the following self-care steps may be helpful.
    • Go for the ginkgo

      Boost mental function by taking 120 to 240 mg a day of a standardized herbal extract of Ginkgo biloba

    • Explore acetyl-L-carnitine

      Taking 1,500 mg a day of this supplement may improve memory, mood, and responses to stress

    • Boost your memory with B vitamins

      Treat deficiencies of vitamins B6 and B12 for improved memory and other brain functions

    • Get moving

      Start a walking program or join an exercise group to gain brain-function benefits

    • Give your brain a workout

      Improve cognitive functioning with a memory-enhancement program


    About This Condition

    A decline in memory and cognitive (thinking) function is considered by many authorities to be a normal consequence of aging.1 , 2 While age-related cognitive decline (ARCD) is therefore not considered a disease, authorities differ on whether ARCD is in part related to Alzheimer's disease and other forms of dementia3 or whether it is a distinct entity.4 , 5 People with ARCD experience deterioration in memory and learning, attention and concentration, thinking, use of language, and other mental functions.6 , 7

    ARCD usually occurs gradually. Sudden cognitive decline is not a part of normal aging. When people develop an illness such as Alzheimer's disease, mental deterioration usually happens quickly. In contrast, cognitive performance in elderly adults normally remains stable over many years, with only slight declines in short-term memory and reaction times.8

    People sometimes believe they are having memory problems when there are no actual decreases in memory performance.9 Therefore, assessment of cognitive function requires specialized professional evaluation. Psychologists and psychiatrists employ sophisticated cognitive testing methods to detect and accurately measure the severity of cognitive decline.10 , 11 , 12 , 13 A qualified health professional should be consulted if memory impairment is suspected.

    Some older people have greater memory and cognitive difficulties than do those undergoing normal aging, but their symptoms are not so severe as to justify a diagnosis of Alzheimer's disease. Some of these people go on to develop Alzheimer's disease; others do not. Authorities have suggested several terms for this middle category, including "mild cognitive impairment"14 and "mild neurocognitive disorder."15 Risk factors for ARCD include advancing age, female gender, prior heart attack , and heart failure .


    People with ARCD experience deterioration in memory and learning, attention and concentration, thinking, use of language, and other mental functions.

    Healthy Lifestyle Tips

    Cigarette smokers and people with high levels of education appear to have some protection against ARCD.16 The reason for each of these associations remains unknown. However, as cigarette smoking generally is not associated with other health benefits and results in serious health risks, doctors recommend abstinence from smoking, even by people at risk of ARCD.

    A large, preliminary study in 1998 found associations between hypertension and deterioration in mental function.17 Research is needed to determine if lowering blood pressure is effective for preventing ARCD.

    A randomized, controlled trial determined that group exercise has beneficial effects on physiological and cognitive functioning, and well-being in older people. At the end of the trial, the exercisers showed significant improvements in reaction time, memory span, and measures of well-being when compared with controls.18 Going for walks may be enough to modify the usual age-related decline in reaction time. Faster reaction times were associated with walking exercise in a British study.19 The results of these two studies suggest a possible role for exercise in preventing ARCD. However, controlled trials in people with ARCD are needed to confirm these observations.

    Psychological counseling and training to improve memory have produced improvements in cognitive function in persons with ARCD.20 , 21 , 22

    Eating Right

    The right diet is the key to managing many diseases and to improving general quality of life. For this condition, scientific research has found benefit in the following healthy eating tips.

    Recommendation Why
    Add some caffeine
    Give your brain a boost with caffeine. Coffee and, to a lesser degree, tea have been linked to improved mental function in seniors.

    Caffeine may improve cognitive performance. Higher levels of coffee consumption were associated with improved cognitive performance in elderly British people in a preliminary study.23 Older people appeared to be more susceptible to the performance-improving effects of caffeine than were younger people. Similar but weaker associations were found for tea consumption. These associations have not yet been studied in clinical trials.

    Be pro-antioxidant
    Animal studies suggest that diets high in antioxidant-rich foods, such as spinach and strawberries, may help slow ARCD.

    Animal studies suggest that diets high in antioxidant -rich foods, such as spinach and strawberries, may be beneficial in slowing ARCD.24 Among people aged 65 and older, higher vitamin C and beta-carotene levels in the blood have been associated with better memory performance,25 though these nutrients may only be markers for other dietary factors responsible for protection against cognitive disorders.

    Go Mediterranean
    A Mediterranean diet, which is high in monounsaturated fatty acids (such as olive oil), may protect against ARCD.

    In the elderly population of southern Italy, which eats a typical Mediterranean diet, high intake of monounsaturated fatty acids (e.g., olive oil) has been associated with protection against ARCD in preliminary research.26 However, the monounsaturated fatty acid content of this diet might only be a marker for some other dietary or lifestyle component responsible for a low risk of ARCD.


    What Are Star Ratings?

    Our proprietary "Star-Rating" system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by some in the medical community, and whether studies have found them to be effective for other people.

    For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.

    3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.

    2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

    1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

    Supplement Why
    3 Stars
    1,500 mg daily
    Several clinical trials suggest that this supplement delays onset of ARCD and improves overall cognitive function in the elderly

    Several clinical trials suggest that acetyl-L-carnitine delays onset of ARCD and improves overall cognitive function in the elderly. In a controlled clinical trial, acetyl-L-carnitine was given to elderly people with mild cognitive impairment. After 45 days of acetyl-L-carnitine supplementation at 1,500 mg per day, significant improvements in cognitive function (especially memory) were observed.27 Another large trial of acetyl-L-carnitine for mild cognitive impairment in the elderly found that 1,500 mg per day for 90 days significantly improved memory, mood, and responses to stress. The favorable effects persisted at least 30 days after treatment was discontinued.28 Controlled29 , 30 , 31 and uncontrolled32 clinical trials on acetyl-L-carnitine corroborate these findings.

    3 Stars
    120 to 160 mg daily
    Most, but not all, clinical trials have found this herb to be a safe and effective treatment for ARCD.

    Most33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 but not all41 clinical trials, many of them double-blind, have found ginkgo supplementation to be a safe and effective treatment for ARCD.42

    3 Stars
    300 mg daily of bovine-derived supplement
    Bovine-derived PS (phosphatidylserine) has been shown to improve memory, cognition, and mood in the elderly. To date, most evidence suggests that soy-derived PS is not effective for ARCD.

    Phosphatidylserine (PS) derived from bovine brain phospholipids has been shown to improve memory, cognition, and mood in the elderly in at least two placebo-controlled trials. In both trials, geriatric patients received 300 mg per day of PS or placebo. In an unblinded trial of ten elderly women with depressive disorders, supplementation with PS produced consistent improvement in depressive symptoms, memory, and behavior after 30 days of treatment.43 A double-blind trial of 494 geriatric patients with cognitive impairment found that 300 mg per day of PS produced significant improvements in behavioral and cognitive parameters after three months and again after six months.44

    Most research has been conducted with PS derived from bovine tissue, but what is available commercially is made from soy. The soy- and bovine-derived PS, however, are not structurally identical.45 Doctors and researchers have debated whether the structural differences could be important,46 , 47 but so far only a few trials have studied the effects of soy-based PS.

    Preliminary animal research shows that the soy-derived PS does have effects on brain function similar to effects from the bovine source.48 , 49 , 50 An isolated, unpublished double-blind human study used soy-derived PS in an evaluation of memory and mood benefits in nondemented, nondepressed elderly people with impaired memories and accompanying depression .51 In this three-month study, 300 mg per day of PS was not significantly more effective than a placebo. In a double-blind study, soy-derived PS was administered in the amount of 300 or 600 mg per day for 12 weeks to people with age-related memory impairment. Compared with the placebo, soy-derived PS had no effect on memory or on other measures of cognitive function.52 While additional research needs to be done, currently available evidence suggests that soy-derived PS is not an effective treatment for age-related cognitive decline.

    2 Stars
    Refer to label instructions
    Animal studies have found this Ayurvedic herb enhances several aspects of mental function and learning ability, and there is some preliminary research that it improves mental function in humans.

    Animal studies have found the Ayurvedic herb bacopa has constituents that enhance several aspects of mental function and learning ability.53 , 54 , 55 A controlled study found that a syrup containing an extract of dried bacopa herb given to children improved several measures of mental performance.56 A double-blind trial in adults found that a standardized extract of bacopa (300 mg per day for people weighing under 200 lbs and 450 per day for people over 200 lbs) improved only one out of several measures of memory function after three months.57 Another double-blind trial lasting twelve weeks found 300 mg per day of bacopa improved four out of fifteen measures of learning, memory, and other mental functions in adults.58 A third double-blind trial found that 300 mg per day of bacopa improved memory acquisition and retention in healthy elderly people.59 Similar results were found in a 12-week double-blind study of elderly individuals who had no evidence of dementia.60 A fourth double-blind study found no effects on mental function in a group of healthy adults given 300 mg of standardized bacopa and tested two hours later. Bacopa has not been tested on people with memory problems.61

    2 Stars
    Folic Acid (In people with high homocysteine)
    800 mcg per day
    Folic acid has been shown to slow the rate of cognitive decline in people with high homocysteine levels and in elderly people.

    In a double-blind trial, elderly people with high homocysteine levels received 800 mcg of folic acid per day or a placebo for three years. Compared with placebo, folic acid supplementation significantly slowed the rate of decline of memory and of other measures of cognitive function.62

    2 Stars
    100 to 150 mcg two to three times per day
    Huperzine A, an extract from a Chinese medicinal herb, has been found to improve cognitive function in seniors with memory disorders.

    Huperzine A, an isolated alkaloid from the Chinese medicinal herb huperzia (Huperzia serrata), has been found to improve cognitive function in elderly people with memory disorders. One double-blind trial found that huperzine A (100 to 150 mcg two to three times per day for four to six weeks) was more effective for improving minor memory loss associated with ARCD than the drug piracetam.63 More research is needed before the usefulness of huperzine A is confirmed for mild memory loss associated with ARCD.

    2 Stars
    150 mg per day
    A study of healthy senior people reported that supplementing daily with Pycnogenol improved some measures of memory after three months, compared with a group taking a placebo.
    A double-blind study of healthy senior people reported that 150 mg per day of Pycnogenol improved some measures of memory after three months, compared with a group taking a placebo.64
    2 Stars
    30 to 60 mg daily
    Vinpocetine has been shown to improve dementia symptoms in patients with various brain diseases.

    A double-blind trial found both 30 mg and 60 mg per day of vinpocetine improved symptoms of dementia in patients with various brain diseases.65 Another double-blind trial gave 30 mg per day of vinpocetine for one month, followed by 15 mg per day for an additional two months, to people with dementia associated with hardening of the arteries of the brain, and significant improvement in several measures of memory and other cognitive functions was reported.66 Other double-blind trials have reported similar effects of vinpocetine in people with some types of dementia or age-related cognitive decline.67 , 68 However, a study of Alzheimer patients in the United States found vinpocetine given in increasing amounts from 30 mg to 60 mg per day over the course of a year neither reversed nor slowed the decline in brain function measured by a number of different tests.69

    2 Stars
    Vitamin B12 (Vitamin B12 Deficiency)
    Consult a qualified healthcare practitioner
    Improved brain function among seniors has been observed after correcting vitamin B12 deficiency with injections, but oral vitamin B12 has not been studied for ARCD. People with ARCD should be tested for vitamin B12 deficiency.

    Supplementation with vitamin B12 may improve cognitive function in elderly people who have been diagnosed with a B12 deficiency. Such a deficiency in older people is not uncommon. In a preliminary trial, intramuscular injections of 1,000 mcg of vitamin B12 were given once per day for a week, then weekly for a month, then monthly thereafter for 6 to 12 months. Researchers noted "striking" improvements in cognitive function among 22 elderly people with vitamin B12 deficiency and cognitive decline.70 Cognitive disorders due to vitamin B12 deficiency may also occur in people who do not exhibit the anemia that often accompanies vitamin B12 deficiency. For example, in a study of 141 elderly people with cognitive abnormalities due to B12 deficiency, 28% had no anemia. All participants were given intramuscular injections of vitamin B12, and all showed subsequent improvement in cognitive function.71

    Vitamin B12 injections put more B12 into the body than is achievable with absorption from oral supplementation. Therefore, it is unclear whether the improvements in cognitive function described above were due simply to correcting the B12 deficiency or to a therapeutic effect of the higher levels of vitamin B12 obtained through injection. Elderly people with ARCD should be evaluated by a healthcare professional to see if they have a B12 deficiency. If a deficiency is present, the best way to proceed would be initially to receive vitamin B12 injections. If the injections result in cognitive improvement, some doctors would then recommend an experimental trial with high amounts of oral B12, despite a current lack of scientific evidence. If oral vitamin B12 is found to be less effective than B12 shots, the appropriate treatment would be to revert to injectable B12. At present, no research trials support the use of any vitamin B12 supplementation in people who suffer from ARCD but are not specifically deficient in vitamin B12.

    2 Stars
    Vitamin B12 and Folic Acid
    100 mcg per day of vitamin B12 and 400 mcg per day of folic acid
    In a double-blind trial, supplementing with vitamin B12 and folic acid for 2 years slowed the rate of cognitive decline, compared with placebo, in elderly volunteers.
    In a double-blind trial, supplementation with 100 mcg per day of vitamin B12 and 400 mcg per day of folic acid for 2 years slowed the rate of cognitive decline, compared with placebo, in elderly volunteers.72
    2 Stars
    Vitamin B6
    20 mg daily
    There is evidence that supplementing with vitamin B6 (pyridoxine) may improve memory performance, especially in people who are deficient.

    Vitamin B6 (pyridoxine) deficiency is common among people over age 65.73 A Finnish study demonstrated that approximately 25% of Finnish and Dutch elderly people are deficient in vitamin B6 as compared to younger adults. In a double-blind trial, correcting this deficiency with 2 mg of pyridoxine per day resulted in small psychological improvements in the elderly group. However, the study found no direct correlation between amounts of vitamin B6 in the cells or blood and psychological parameters.74 A more recent double-blind trial of 38 healthy men, aged 70 to 79 years, showed that 20 mg pyridoxine per day improved memory performance, especially long-term memory.75

    2 Stars
    Vitamin B6, Vitamin B12, and Folic Acid (For women with low dietary intake )
    Refer to label instructions
    In women with cardiovascular disease or related risk factors and low dietary intake of folic acid, vitamin B6, and vitamin B12, supplementing with a combination of these nutrients may protect against age-related cognitive decline.

    In a study of female health professionals who had cardiovascular disease or cardiovascular disease risk factors, daily supplementation with folic acid (2.5 mg), vitamin B6 (50 mg), and vitamin B12 (1 mg) for 5.4 years had no effect on cognitive function. However, supplementation appeared to prevent age-related cognitive decline in the 30% of women who had low dietary intake of B vitamins.76

    Supplementation with homocysteine-lowering B vitamins (folic acid, vitamin B12, and vitamin B6) also slowed the rate of brain atrophy in elderly people who had mild cognitive impairment and high homocysteine levels.77

    1 Star
    Refer to label instructions
    Some, though not all, research has found astaxanthin might protect the brain from age-related oxidative damage.
    Astaxanthin is a member of the carotenoid family with strong antioxidant properties that might protect the brain from age-related oxidative damage.78 In a preliminary study, 12 mg per day of astaxanthin given to people with complaints of age-related forgetfulness for twelve weeks improved some measures of brain function,79 but a double-blind trial using similar amounts found no significant effects of astaxanthin on cognitive impairment compared to a placebo.80
    1 Star
    50 mg every other day
    In one study, long-term beta-carotene supplementation slowed the loss of cognitive function in middle-aged healthy males.

    Caution: Synthetic beta-carotene has been linked to increased risk of lung cancer in smokers. Until more is known, smokers should avoid all beta-carotene supplements.

    In a double-blind trial, supplementation with beta-carotene in the amount of 50 mg every other day for 18 years appeared to slow the loss of cognitive function in middle-aged healthy males. Short-term supplementation (one year) was not beneficial.81

    1 Star
    Refer to label instructions
    Cognitive function is linked to adequate sleep and normal sleep-wake cycles, which are partially regulated by the hormone melatonin. The long-term effects of melatonin are unknown, use under a doctor's supervision.

    Melatonin is a hormone secreted by the pineal gland in the brain. It is partially responsible for regulating sleep-wake cycles. Cognitive function is linked to adequate sleep and normal sleep-wake cycles. Cognitive benefits from melatonin supplementation have been suggested by preliminary research in a variety of situations and may derive from the ability of melatonin to prevent sleep disruptions.82 , 83 , 84 , 85 A double-blind trial of ten elderly patients with mild cognitive impairment showed that 6 mg of melatonin taken two hours before bedtime significantly improved sleep, mood, and memory, including the ability to remember previously learned items.86 However, in a double-blind case study of one healthy person, 1.6 mg of melatonin had no immediate effect on cognitive performance.87

    The long-term effects of regularly taking melatonin supplements remain unknown, and many healthcare practitioners recommend that people take no more than 3 mg per evening. A doctor familiar with the use of melatonin should supervise people who wish to take it regularly.

    1 Star
    Refer to label instructions
    In a preliminary trial of individuals with mild cognitive impairment and low blood levels of selenium, the improvement in measures of cognitive function was significantly greater in the group eating Brazil nuts than in the control group.
    In a preliminary trial, elderly individuals with mild cognitive impairment and low blood levels of selenium consumed one Brazil nut per day (providing an estimated 289 mcg of selenium per day) or no Brazil nuts (control group) for 6 months. The improvement in measures of cognitive function was significantly greater in the group eating Brazil nuts than in the control group.88 Additional research is needed to determine whether taking selenium supplements or eating Brazil nuts would be beneficial for people with normal blood levels of selenium.
    1 Star
    Vitamin C
    Refer to label instructions
    Use of vitamin C, alone or with vitamin E, has been associated with better cognitive function and a reduced risk of certain forms of dementia (not including Alzheimer's disease).

    Use of vitamin C or vitamin E supplements, or both, has been associated with better cognitive function and a reduced risk of certain forms of dementia (not including Alzheimer's disease).89 Clinical trials of these antioxidants are needed to confirm the possible benefits suggested by this study.

    1 Star
    Vitamin E
    Refer to label instructions
    Use of vitamin E, alone or with vitamin C, has been associated with better cognitive function and a reduced risk of certain forms of dementia (but not Alzheimer's disease).

    Use of vitamin C or vitamin E supplements, or both, has been associated with better cognitive function and a reduced risk of certain forms of dementia (not including Alzheimer's disease).90 Clinical trials of these antioxidants are needed to confirm the possible benefits suggested by this study.


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