Hypothyroidism (low thyroid hormone, TH) is a condition that causes a decline in metabolic function that slows arterial blood flow and impedes the delivery of key nutrients and oxygen to the brain. As a result, the person both thinks and moves more slowly. If not treated in time, the condition progresses to cause the blood vessels of the brain to age prematurely and irreversibly harden (atherosclerosis). Furthermore, hypothyroidism also reduces the number of dendrite connections between brain cells.
Thyroid function is integral in maintaining overall youth. Cognitive symptoms of hypothyroidism include sluggishness, slowed thinking, difficulty concentrating and poor memory, most notable upon waking up or after resting. Not surprisingly, thyroid therapy can reverse these signs, says Dr. Thierry Hertoghe, Secretary General of the Belgium Medical Association and expert in HRT: "Thyroid supplements are really great at enhancing alertness and intelligence to such an extent that many physicians consider thyroid hormones to be the hormone of intelligence...the efficacy with which thyroid treatment reverses failing memories of people definitely low in thyroid hormones depends on when the therapy is started. In general, the sooner thyroid supplements are given, the better."
Although primarily associated with sexual performance, testosterone is an important memory hormone. Men and women demonstrating a better spatial memory (the ability to manipulate precise movements in all dimensions) generally have more testosterone in their blood. According to Dr. Hertoghe, "When testosterone therapy is taken by transsexual women (women who feel themselves more as men and try medical treatment to make their body look more like the body of a male), these masculinized women become more proficient in spatial tasks, but lose their previous language fluency, a typical characteristic of women."
Most of the research on the effects of hormones on memory has concentrated on estrogen, with good cause. Through studies of the millions of middle-aged women on an estrogen replacement therapy (ERT) program, it has been concluded that estrogen not only counteracts the effects of menopause but also can reenergize slowed cognition. Researchers around the globe are finding that it can markedly sharpen a woman's thinking. It is important to note that estrogen, while available as either a tablet or injection, is speculated to have better uptake to the brain in its injectable form.
Dr. Barbara Sherwin of McGill University, a leading researcher on this subject, reports there is "reason to believe that this sex steroid might enhance memory," while noting that estrogen does not have the same impact on all kinds of memory. In healthy young women, it appears of most benefit for short and long-term verbal memory and especially "paired-associate" memory (how well one remembers new information). On the other hand, the hormone seemed to have no effect on, or sometimes weakened, spatial memory.
In one of the studies, 28 women on ERT and 43 women not on ERT were read a short paragraph and, after 30 minutes, asked to recall as much as they could about it. The women on estrogen remembered much more, leading the researchers to conclude that the hormone not only helped their memory but also their ability to learn new material. While Sherwin admitted that the difference in performance between the two groups was not huge, she did report that the ERT treated women recall telephone numbers, instructions and directions more easily.
Some scientists have found that estrogen's influence on women's memory is apparent during normal menstrual cycles. A study of 45 women at the University of Western Ontario discovered that during the high-estrogen phase of their cycle, women did noticeably better on verbal fluency tests (saying as many words as possible starting with a certain letter and within a certain time).
The effects of estrogen on the thought processes of post-menopausal women have been examined since the hormone was first synthesized. A number of tests of elderly women treated with estrogen have shown that it can produce major gains not only in verbal memory but other kinds of mental functioning as well. Dr. Sherwin says that various studies provide "compelling evidence" of the benefits of estrogen replacement for aging minds. Researchers at Stanford University who tested the memories of 144 women age 55 to 93, half on estrogen and half not, found that it definitely made a difference for remembering names and faces.
In studies of estrogen and brain activity, researchers have found that it has a stronger influence on mental functions governed by the left hemisphere. The left side of your brain directs language, verbal skills and manual dexterity. Also, a healthy circulation of estrogen through the brain stimulates the production of nerve growth factor (NGF), which the brain manufactures to protect neurons vital for memory. If there is not sufficient estrogen in the brain, NGF production drops and memory cells weaken.
DHEA, THE MOTHER OF HORMONES
A hormone reputed to boost the memories of both men and women is DHEA, known as the 'mother of hormones' because the body converts it to dozens of others (its offspring include estrogen, androgens, testosterone, progesterone and corticosterone). DHEA is a neuro-steroid hormone produced by our adrenal glands in a steady stream until around age 30 when the flow beings to slack. By age 65, our bodies produce only a small fraction of DHEA as in our 20s. While DHEA is usually recommended for its anti-aging powers, part of its magic, say some doctors, is that it may boost your memory.
An investigation at Bates College in Maine that looked at how various steroids effect memory found that DHEA was a standout. Using female rats, researchers fed them 6 different steroids then put them through memory and learning tests. Those on DHEA-S (the sulfate form with solubility properties similar to plain DHEA) particularly excelled on tests of working and long-term memory. In the discussion of their findings and comparisons with other research, Drs. Cheryl Frye and Jodi Sturgis concluded, "This confirms that DHEA's memory enhancing effects...are not unique to this species, sex or memory task."
Another researcher, Eugene Roberts at the Beckman Research Institute in La Jolla, California, may have learned why DHEA works so well. In his work with rats, he discovered that DHEA stimulates production of a key brain cell messenger and the formation of branches that connect brain cells. DHEA is no magic bullet for a failing memory. The research on its influence on thinking and memory has so far been limited to animals -- which do not have as much of the hormone as humans, so scientists must theorize about how it could effect the human brain. Nevertheless, they have found that it stimulates neuronal growth in animal brains. DHEA also helps balance the body's production of potentially hazardous stress hormones, namely glucocorticoids, which may negatively effect tissues like those in the memory headquarters, the hippocampus. HGH
HGH, the most abundant hormone produced within the brain, is another candidate as a memory repair hormone. HGH and its derivative IGF-1 both act as growth and repair factors for nerves and have shown activity in helping the aged brain remodel and reshape its neurocerebral matrix connections, a critical process for active and effective memory and intelligence. It is now undergoing multicenter trials as a treatment for Alzheimer's and other neurodegenerative diseases of aging.
By the time we are 50 or 60, we pump out 80% less HGH than in our youth. HGH not only feeds our muscles, bones and tissues, but also our brains. As you age, your brain loses many of its receptors for HGH, which compounds the deficiency and may well explain why memory slides as the years tick by.
Scientists have found that it raises the level of B-endorphin, the neurochemical that can make us feel energetic and "high," and lowers the amount of dopamine, a neurochemical that agitates us. By reducing the amount of dopamine that might circulate, HGH may well be making it easier for us to concentrate and remember, as well as to help us to avoid becoming cranky and crotchety.
A study at the Free University Hospital in Amsterdam found that men who lacked HGH had poorer iconic memory (the ability to retain a flash of information), short-term, long-term, and perceptual-motor memory than those whose pituitary did produce HGH. Yet most of the subjects had low HGH from birth, which might have also effected their brain development. Further positive results come from a Japanese study testing rats at the Fujisawa Pharmaceutical Company. Here, researchers have found that low levels of HGH almost definitely produced poor thinking and memory.
Dr. Bengt-Ake Bengtsson, a Swedish endocrinologist, has been actively researching HGH and has published an impressive number of studies on the use of HGH, especially in adults who are deficient in it. He believes, "We are just beginning to scratch the surface of the importance of growth hormone in cognition, memory and brain function."
NUTRITIONAL NOURISHMENT FOR THE BRAIN
There is no simpler way to feed the brain than through daily dietary intake from quality food sources. The implication of proper dietary selections on cognition in older individuals was elucidated by Ortega and colleagues from the Universidad Complutense in Madrid. They found that the fat and nutrient makeups of diets were responsible for differences in performances on mental scale exams: individuals with satisfactory exam results ate less empty calories. The message: a diet with less fat, saturated fat, and cholesterol, and more carbohydrate, fiber, vitamins (especially folate, vitamins C, E, and beta-carotenes), and minerals (such as magnesium potassium, and zinc) may be advisable not only to improve the general health of the elderly but also to improve cognitive function.
Illnesses such as Parkinson's and Alzheimer's diseases are frightening prospects for the older population. Conditions that rob one's ability to think, express oneself and maintain independent living, will - with the assistance of anti-aging physicians and scientists making full use of biochemical, bioengineering, and genetic advancements - become as extinct as typhoid fever and polio. Until then, one of the best ways to stave the onset of brain disease is to take full advantage of those nutrients shown to prolong mental performance.
The antioxidant vitamins, A (beta carotene), C and E, in addition to the mineral selenium and bioflavonoids, by virtue of their capacity to counter free radical damage, offer brain cells protection from oxidation and deterioration.
The Rotterdam Study, conducted by Jama and associates at the Erasmus University Medical School in Rotterdam, The Netherlands, found that a lower intake of beta carotene corresponded to a higher incidence of impaired cognitive function. Schmidt and his colleagues at the Karl-Franzens University in Austria conducted a study to assess the antioxidant levels in middle-aged and older individuals as it pertained to cognition. As confirmation and extension of Jama's study, Schmidt found that low test results on a standardized dementia scale correlated to depressed blood levels of beta carotene and alpha-tocopherol (Vitamin E).
Recent studies have elucidated a role for Vitamin C as a factor in cognitive performance. Gale and colleagues from the University of Southampton in England discovered that cognitive function was poorest among those with the lowest vitamin C status, and that those study participants who did not perform well on the administered mental exam had an increased risk of death from stroke resulting from vascular impairment. Gale concluded that "Vitamin C status may be a determinant of cognitive function in elderly people through its effect on atherogenesis. A high vitamin C intake may protect against both cognitive impairment and cerebrovascular disease."
The role of Vitamin C as a free radical scavenger was investigated by Riviere and colleagues from the Hopital La Grave-Casselar in Toulouse, France. Finding that regardless of the actual dietary intake through foods, actual blood levels of vitamin C were depressed in individuals with Alzheimer's disease in a manner reflective of the severity of the illness. Because actual intake was not a relevant factor, this study confirms that free radicals cause damage that results with in cognitive impairment.
Indeed, dietary antioxidants may serve a critical role in protecting against cognitive impairment associated with aging.
Vitamin B-12 (also known as cobalamin) deficiency has been implicated as a cause of vascular disease. Allen and colleagues from the University of Colorado Health Sciences Center in Denver found that cobalamin deficiency is common in the older population. Additionally, Allen's study found that B-12 therapy lowers homocysteine levels, a new marker of heart disease.
Recent studies now find an important role for B-12 in cognition. Cunha and colleagues from Brazil administered B-12 to cobalamin-deficient patients experiencing dementia. Those who fared the best on treatment, showing notable improvement on mental state exam, were patients who succumbed to dementia more recently -- within the last two years. Consequently, Cunha suggested that B-12 screening would be a valuable tool in patients with recent changes in mental performance. In an assessment of veterans, Bernard and associates from the University of Oklahoma College of Medicine at Oklahoma City found that veterans with subnormal B-12 blood levels experienced deficits in cognitive performance.
Folic acid is a coenzyme that helps cells with the process of cell division and replication, and as such, is most well known as the vitamin that prevents birth defects. Ebly and colleagues at the University of Calgary in Alberta, Canada, discovered that low blood levels of folate correlated to an increased likelihood of stroke. Additionally, dementia and depression were associated with those with low folate levels. The individuals who showed cognitive impairment without dementia were prone to difficulties with short-term memory.
Thiamine (Vitamin B-1) is established as a circulatory enhancer and for maintaining muscle tone of the heart, stomach and intestines. Recent studies implicate thiamine in cognitive dysfunction. On a group of Alzheimer's patients who were not deficient in B-1, Mimori and colleagues at the Hiroshima University School of Medicine in Japan found that oral supplementation of a thiamine derivative had a mild beneficial effect on emotional as well as intellectual functions. This is an important clue for researchers investigating the biological origins of Alzheimer's Disease.
Inositol, a B vitamin necessary for fat and cholesterol metabolism and for fat mobilization from the liver, shows therapeutic benefit in Alzheimer's patients. Barak and associates from the Abarbanel Mental Health Center in Bat Yam, Israel, found that language and orientation skills were significantly improved, implying a potential therapeutic role for high-dose inositol therapy in Alzheimer's Disease. Amino Acids
The twenty-nine molecules known as amino acids are regarded as the 'building blocks of protein,' reflecting their integral role in cellular functions. Without amino acids, our cells would, quite literally, fail to hold their shape. Because all cognitive processes rely on neurotransmission (the communication of electrical impulses through nerve cells), proper amino acid levels are critical to mental performance.
If you fail to receive sufficient essential amino acids through dietary means, your body is forced to do without them. This may lead to the onset of illness, particularly in those people with metabolic errors that exacerbate the consequences of amino acid deficiencies. Thus, oral supplementation of amino acids has been found to be a generally safe and effective method to reinforce cognitive health.
In a study of rats, Dawson and colleagues at the University of Florida College of Pharmacy at Gainesville found a significantly reduction in the level of taurine in the part of the brain associated with spatial learning performance. This depressed taurine level was correlated to reduced dopamine, implicated in both Alzheimer's and Parkinson's Diseases. Whereas aged rats without behavioral impairment had more modest taurine reductions, this study demonstrated the significance of age-related declines of taurine. Dawson, in a separate study, also observed that rats on taurine-deficient diets were found to have depressed IGF-1 levels. Dietary supplementation was able to correct "advanced aging [that] results in a taurine-deficient state."
Tryptophan, through its metabolic conversion to melatonin, is an important brain amino acid. Maurizi found that stress or a dietary deficiency of tryptophan results with reduced availability of serotonin and melatonin. Coupled with the naturally reduced ability to produce melatonin with age, tryptophan's role in the bioclock of life cannot be understated. Melatonin deficiency and biorhythm irregularities have been associated with affective diseases, sleep disorders, Alzheimer's Disease, and other diseases of aging
Deficiencies of acetyl-L-carnitine has also been linked to cognitive impairment. Administering it for a period of three months, Passeri and associates at the University of Parma, Italy, found improvements in dementia and memory, as well as in attention and verbal skills. When given to Alzheimer's patients, Pettegrew and colleagues at the University of Pittsburgh School of Medicine found that acetyl-L-carnitine exerted a protective action, stabilizing test scores from mental assessments.
A group of molecules found in abundance in the membranes of nerve cells, red blood cells, and cellular powerplants (mitochondria), phospholipids are a necessary fatty compound. Their presence maintains an elasticity and permeability of cell membranes that permits the continual flow of nutrients and oxygen. Without phospholipids, cell membranes would harden and cells would starve and die. Delion and colleagues at the Laboratoire de Biophysique Medicale et Pharmaceutique in France found that the decrease in the major phospholipids is age-dependent. This decline could be corrected through a diet including polyunsaturated fatty acids (PUFAs), resulting with improvements in neurotransmission.
Phosphatidylserine (PS) is implicated in brain aging. As we age, levels of acetylcholine, critical to the ability of neurons to communicate, decline. Jeglinski and associates from the Nencki Institute of Experimental Biology in Poland found that PS promotes the release of acetylcholine, a critical neurochemical in the encoding of memory, in a study conducted on aging rats.
Botanical agents may become an important accessory armament in the war against cognitive impairment. While a current lack of clinical studies plagues the complete acceptance of botanical agents as a reputable therapy, the public's interest in this type of non-drug approach will most certainly result with both validation and acceptance.
Ginkgo biloba extract is the most extensively studied herbal remedy for cognitive deficits. Recognized for its ability to protect cell membranes from free radical damage, gingko biloba is also responsible for improvements in short-term memory. In patients with Parkinson's Disease, measurable brain wave changes upon administration with gingko were found: specifically, theta waves, the wave of sleep and unconsciousness, were found to retreat in prominence.
Researchers are also evaluating ginseng as a cognitive agent. Its active ingredient, ginsenoside, is suspected to facilitate learning and memory. Ginseng can cause an increase in the number of synapses formed in the hippocampal region of the brain, responsible for learning and memory and an area that is hard hit by both aging and stress. Ginseng's nootropic abilities include enhancement of immune function, mediation of age-related motor and behavioral declines, and promotion of neuronal function.
Cognitive Decline is Not Inevitable
Researchers at the University of California Davis School of Medicine have demonstrated that changes in cognitive function are not a normal part of aging. While the risk of Alzheimer's Disease is increased for people with atherosclerosis, diabetes, and those with the apolipoprotein E4 gene thought to predispose to early onset of Alzheimer's, UC's study of nearly 6000 seniors demonstrated that 70% of them showed no significant decline in cognition.
Take measures to promote cerebrovascular health and reduce your risk factors for Alzheimer's. As for role of genetics, a new vaccine and new medications are on the horizon - in as little as five years, age-related cognitive decline may be another dreaded disease of aging eliminated by anti-aging biotechnology.
There is no need to grow senile. There is no need to physically degrade, either: HGH and optional therapeutic nutrients can help you to maintain muscle tone and skeletal strength for a lifetime.
YOU ARE WHAT YOU EAT
Reversing death begins in the colon - but aging starts at your lips.
- Take a good look at your dietary habits, then take a look in the mirror. Do you like what you see? If not, seek a nutritionist to act as your dietary coach.
- Are you eating too much fried food or commercially prepared products?
- Are you meeting the new food pyramid's recommendations of 5 servings a day of fruits and vegetables? Ten servings daily is the ideal target.
How many times a week do you eat out, and during those times, do you ever ask how your food is prepared?
Select foods with high content of the brain amino acids
-- Taurine: fish, organ meats
-- Tryptophan: wild game, pork, cottage cheese, wheat germ, duck, turkey
--* Carnitine: beef
If you are a vegetarian, make certain that you are consuming adequate alternative sources of protein to provide a complete source of amino acids.
- Select first pressed, cold processed oils for cooking and food preparation. As the Mediterranean population has demonstrated, virgin olive oil is an excellent choice for healthy fatty acids.
STAY MENTALLY ACTIVE
- Constantly build new mental circuits. Play chess, learn Tai Chi, go dancing, guess the answers on Jeopardy, or take an adult ed class: just keep the mental muscle in shape and say 'no' to old age.
- Volunteerism and hobbies are also great brain stimulators, too.
Source; The American Academy of Anti-Aging Medicine