We Grow Old? – Redux, Part 8
Fast Do We Decline Mentally As We Age?
In the last installment in the "Must We Grow Old?" series in GoF, did you have trouble following my tables showing the effects of aging upon IQ? So did I! You can see them in their original form at “http:hiqnews.megafoundation.org/GoF_Issue154.doc”. What the tables were trying to show was that although our IQ scores on updated versions of a given IQ test may drop as we grow older, this may be at least partially because each updated revision of the test is made a little harder in order to allow for the Flynn Effect. The Flynn Effect refers to the fact that the average IQ has been rising by about 3 points per decade for at least the last 10 decades. Rather than raise the average IQ to 130, psychometrists have kept it at 100, by definition, but this tends to mask the fact that average IQ scores are, in fact, rising. If, in 1939, at the age of 20, you had taken the Wechsler-Bellevue IQ test when it was first introduced and had gotten an IQ score at the 3.33-sigma level (IQ = 150, sigma = 15, or IQ = 153, sigma = 16)), and then you recently took the WAIS-III (Wechsler Adult Intelligence Scale-III) IQ test in 1997 at the age of 78, you could expect to get only a 2.19-sigma IQ (IQ = 133, standard deviation = 15, or IQ = 135, standard deviation = 16) score on the WAIS-III simply because the WAIS-III is 17-points-of-IQ more difficult than the Wechsler-Bellevue. Any additional decline in IQ below 2.33-sigma could be attributed to an actual cognitive decline with aging.
If you're between the ages of 25 and 44, a maximum-scaled score (perfect score) on the WAIS-R will put you at the 4.33-sigma level (IQ = 169.5, s = 16) among your 25-to-44 age peers. If you're between the ages of 70 and 74, it will put you at the 5.6-s level (IQ = 189, s = 16) of uncommonality among your 70-74 age peers, reflecting the drop in IQ scores among the earlier-born. The fact that there's a 19.5 difference in IQ between 25-44 and 70-74 (an age difference of 30-40 years) suggests to me that significant age-related cognitive decline is occurring in addition to the Flynn-effect scoring disparities.
Will Vitamin E Shorten Your Life Span?
Would that I knew! A recent meta-analysis of 19 studies involving 135,967 people in North America, Europe and China concluded that someone taking 400 IU a day for five years would increase their risk of death by 5% (http://www.washingtonpost.com/wp-dyn/articles/A39261-2004Nov10.html).
"The study found no increased risk from lower doses, particularly at doses of 200 international units or below, and perhaps even a benefit. Although the study did not examine how high-dose Vitamin E might increase the risk of death, other studies have suggested that the substance may boost the danger of heart attacks and strokes, perhaps by affecting blood clotting or blocking the beneficial effects of other nutrients, the researchers said. Other researchers, however, questioned the new findings, saying the analysis was flawed and that other studies have shown a benefit from taking Vitamin E and other antioxidants. Maret G. Traber, an Oregon State University researcher who served on a National Academy of Sciences panel that evaluated Vitamin E, agreed. 'Vitamin E won't kill you," Traber said. "Everything we know about Vitamin E is that it's incredibly safe.'"
Celebrex, Aleve and Your Heart
The Life Extension Foundation has an interesting explanation of the mechanism whereby COX-2 (Cyclo-Oxygenase-2) inhibitors lead to cardiovascular damage (see the figure below). Living organisms draw upon two types of long-chain fatty acids to synthesize pro-inflammatory and anti-inflammatory eicosanoids. Pro-inflammatory eicosanoids play important roles in wound healing and in mounting the immune response. Anti-inflammatory eicosanoids balance the pro-inflammatory eicosanoids. The pro-inflammatory eicosanoids are produced from arachidonic acid, which, in turn, is synthesized from the omega-6 fatty acids found in animal products and in vegetable oils. The anti-inflammatory eicosanoids are generated from the omega-3 fatty acids found in cold-water pelagic fish such as salmon and mackerel, and in such vegetable lipids as flaxseed oil. Arachidonic acid breaks down into the COX-1 intermediary, which gives rise to thromboxane A2, to COX-2, which becomes prostaglandin E2, or to 5-lipooxygenase, which metabolizes to form leukotriene B4. Both prostaglandin E2 and leukotriene B4 trigger inflammatory responses: prostaglandin E2 in joints, and leukotriene E4 in blood vessels.
inhibitors such as Vioxx and Celebrex inhibit the metabolic pathways that lead
to prostaglandin E2, which relieves arthritis pain, but they shift arachidonic
acid breakdown to the generation of more thromboxane A2 and leukotriene B4,
enhancing blood clotting and blood vessel inflammation. The real solution might
lie in reducing the intake of arachidonic acid and upping the consumption of
omega-3 oils. This should reduce
the pro-inflammatory response altogether, rather than shifting it from joints to
Can IQ Be Boosted?
A number of studies have shown that supplementation with omega-3 oils in the third trimester of pregnancy elevates an infant’s adult IQ by a few points, as does inclusion of omega-3 oils in infant formula (Lanting, et al, Lancet, 1994, 344, 1319-22; Horwood & Ferguson, “Breastfeeding and Later Cognitive and Academic Outcomes. ”Pediatrics, 1998, 101, e9; Willatts, et al, “Effect of long-chain polyunsaturated fatty acids in infant formula on problem solving at 10 months of age”. Lancet, 1998, 352; 9129; 688-691.) (Supplementation of children’s diets with omega-3 oils is under investigation in an English school system.) Adult supplementation with omega-3 oils appears to offer a small but statistically significant benefit with respect to cognitive decline with aging. Another study in the journal, Epidemiology, found that 15-month-old toddlers whose mothers ate fish at least once a week had, on average, a 7% larger vocabulary than those whose mothers ate no fish during pregnancy. IQ enhancements of the order of 5 points of IQ are reported in studies of pre-natal and breast-fed infants. Fish oil capsules for pregnant mothers should probably contain molecularly distilled EPA and DHA to avoid environmental toxins. (My wife and I buy ours from the Life Extension Foundation.) (Mercury levels tend to run low in salmon. Eating 3-4 ounces a day of canned wild salmon is also a possibility if morning sickness doesn’t preclude it.)
Some authors have attributed the rapid evolutionary expansion of the human brain to humanity’s diet of marine animals in the lakes of the Ethiopian highlands 150,000 years ago.
Another “brain food” tested in animal models is choline http://www.sciencenews.org/articles/20011103/bob13.asp. Like the omega-3 oils, it is most effective in the latter half of pregnancy and in the animal equivalent of the first few years of infancy. Human trials have only recently begun. There is some evidence that choline, the precursor to acetylcholine, may even benefit adults. Choline administered to pregnant rats and to their infant pups and then discontinued improves brain function throughout life. Choline is found in eggs, seeds, meat, skim milk and peanut butter. Dr. Ray Sahelian, in his book, “Mind Boosters”, recommends choline as a possible “booster”. He also discusses a somewhat more potent (and more expensive) version of choline called “CDP-choline”.
B-Vitamins? Inositol? Lecithin?
It’s conceivable that extra B-vitamins might be beneficial during pregnancy and early infancy. Folic acid is now routinely recommended for pregnant women to prevent neural tube defects. Inositol and other “brain-construction-materials” might also add slightly to final IQ. Since these are common constituents of foods, and since they’ve been available in supplement form at health food stores for decades, it might not hurt to add them to the diets of pregnant mothers-to-be, and of infants. Choline is tasteless. It can be disguised in other food. A fifteenth or twentieth of an ounce would be plenty. It might help, and it shouldn’t do any harm.
Nature vs. nurture: can early stimulation raise adult IQs?
In my book, the jury is still out on this one. Attempts to intervene en masse have met with little success compared to the effort involved. Four often-cited studies, the Early Training Project, the Carolina Abecedarian Project, the Perry Preschool Project, and the Milwaukee Project, show, at best, a long-term improvement of a few points of IQ. In the Milwaukee project, conducted in the latter 60’s, 20 black neonates from the city’s worst ghetto were enrolled in an enrichment program “in comparison with which John Stuart Mill would have been culturally deprived”. The average IQ of their mothers was about 80. The mothers were given jobs and special training. With regard to the Milwaukee Project, Dr. Arthur Jensen, in his book, “The g Factor, concludes (Pg. 342) that, although the IQs of the Milwaukee Project children group when they reached the 4th grade were on average 10 points higher than the average IQ of the control group, “The evident lack of generality, or broad transfer, of the effects of the test group’s previous cognitive treatment indicates that the test-control gain in IQ was ‘hollow’ with respect to g.” However, concerning the Carolina Abecedarian Project (involving 57 children), he concludes that this intervention, showing a 4.6-point improvement in average IQ for the experimental group at age 15, appreciably raised the level of g (pg. 344).
The children in these enrichment programs remained in their compromised environments for the durations of these programs, and after the programs were terminated. The Milwaukee Project children were enrolled in the ghetto elementary schools at the age of 6, and often attended school hungry and stressed. I find myself wondering what would have happened if these enrichment experiments had been tried with gifted children in serene environments (or with African-American children in serene environments). I’ve been struck with the number of successes registered by parents like James Mill, Leo Wiener, and Boris and Sarah Sidis. They set about to produce child prodigies, and they did. Conventional wisdom is that these children happened to be prodigies, anyway, but I wonder how much of this was inspired by their parental stimulation. (I know of another success story in this vein on the part of university psychologist.)
Statistically, about 80% of adult IQ is attributed to genetic factors.
Another straw in the wind is the Flynn Effect. IQ scores have allegedly risen by, perhaps, 27 points since 1916. The idea that these gains are entirely “hollow” with respect to g is a little hard for me to swallow. Nor can it be that IQ gains are limited to the lower half of the bell curve. The revised editions of the WAIS are more difficult at the high end as well as at the middle of the distribution.
It would be a red-letter day if we could boost human IQs 10 to 15 points with nutritional supplementation. If several nutritional maneuvers that individually yield a few points of IQ apiece are independent and additive, this might be possible. The implications for society can hardly be overestimated.
I believe that we’re at the threshold of being able to boost our IQs as a species, with untold consequences.
Does Nutrition Really Help Prevent Degenerative Diseases?
Does all this attention to healthy lifestyle and nutrition really pay off?
Coronary artery disease is recognized as a lifestyle disease (with differing genetic predispositions), and is becoming preventable. Cardiologists now prescribe folic acid, vitamin B6, and vitamin B12 for heart attack patients. For the first time in U. S. medical history, the mortality rate for heart attacks has fallen below the mortality rate for cancer, and this in spite of our burgeoning epidemic of obesity. The British are calling for a 40% reduction in the frequency of heart attacks by 2010, and are arguing that enough is now known about this topic to virtually eliminate heart attacks within 10 years, at least for those under the age of 50. Statins, niacin, fish oils, B-vitamins, exercise, low-fat diets, and, if needed, caloric restriction can greatly reduce the risk of cardiovascular disease. Ray Kurzweil, in his book, “The 10% Solution”. observes that in the celebrated Framingham study, no one with a total-cholesterol-to-HDL ratio below 2.4 ever had a heart attack. This kind of ratio appears among the caloric restricted, and in the recent Washington University Medical School study of the calorie restricted, the researchers found that caloric restriction seems to have cleared the arteries of its practitioners. Once the ratio of total cholesterol to HDL goes below 2.4, it appears that arteries clean themselves out.
Mr. Kurzweil comes from a family with a congenital predisposition toward heart attacks, and is following a 10%-fat diet (making sure that he gets several grams a day of the omega-3 oils).
Blood sugar control is also important in cardiovascular health. This entails avoiding spikes in blood sugar brought on by the intemperate intake of starches. (Chromium supplementation is recommended as an aid to blood sugar control.)
Are Brightly Colored Fruits and Vegetables Protective Against
One of the news items that have appeared recently is the claim that fruits and vegetables aren’t protective against cancer. This conclusion is based upon a Harvard study following more than 100,000 participants for more than 10 years. Protective effects were found for men but not for women. The study didn’t break out different types of fruits and vegetables, and was based upon questionnaires. A similar study of 285,000 European women showed no influence of fruits and vegetables on the development of breast cancer. However, other studies have shown protective effects, and it may be too early to jump to conclusions just yet.
Own Experience with Nutritional Intervention
My own experience has been as follows.
In August, 2003, I was having trouble climbing a flight of stairs. I also had an irregular heartbeat (premature atrial contractions). I was given cardiovascular tests, including treadmill stress tests and ultrasound examinations of my heart, but apparently, things weren’t bad enough that I was singled out for consultation. (One cardiologist said, ”You have a good heart there.”) However, my blood pressure was also elevated, and I didn’t like what was happening. At that point, I went on my weight loss diet, and switched to a caloric restriction regime. Then last February, I was called in for a physical, and as I’ve recounted in GoF 149 (June, 2004), the results were dramatically good. My total cholesterol was 180, my HDL was 71, my triglycerides were 54, and my fasting blood sugar was 81. I began to run 2˝ miles a day. Two months later came the bombshell announcement from the Washington University Medical School research team that volunteers on caloric restriction had comparable numbers, and that ultrasound examinations of their carotid arteries showed them to be clear of obstructions. At the Third Annual Caloric Restriction Conference that Tommie Jean and I attended in November, one of the lead researchers on the Washington University caloric restriction study, presented a slide showing the carotid arteries of a 77-year-old runner and the 82-year-old caloric-restricted volunteer who was the oldest subject in the Washington U. study. The carotid artery of the 77-year-old runner was fuzzed up with atherosclerotic plaque, while the carotid artery of the 82-year-old was clear.
I’m due for another physical in about a month. It will be interesting to see if my serum lipid profile a year into caloric restriction matches my year-ago profile. In the meantime, caloric restriction hasn’t truly reversed aging. I’m sure the sands of the hourglass are continuing to fall, but I’m continuing to run 2˝ miles a day, and have no known health problems.