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Showing posts with label health. Show all posts
Showing posts with label health. Show all posts

Monday, February 03, 2020

Lifestyles that Promote Living Longer and Better



People in many parts of the world are living longer, due largely to improvements in medicine and healthier lifestyle afforded by less poverty. The downside is that the longer one lives the more likely a debilitating disease will emerge, such as cardiovascular disease, cancer, diabetes, or Alzheimer's Disease. For many people, the important thing is not how long they live, but how long they can live without serious physical suffering.

Many studies have established that the incidence of the common debilitating diseases can be reduced or delayed by modifiable lifestyle factors. While genes can obviously affect one’s vulnerability to disease, genes may not be the primary factor in how long or how well one lives. This is suggested, for example, by one study of over 110,000 healthcare professionals (about 1/3 male, 2/3 female) that clearly showed the value of healthy lifestyles.

The investigators queried these subjects and categorized them according to five lifestyle criteria:

    Diet, as assessed using the Alternate Healthy Eating Index, with a score in the upper 40% indicating a healthy diet;
    Smoking (never vs ever);
    Moderate to vigorous physical activity (≥ 30 minutes/day);
    No alcohol consumption above 15 g/day for women, 30 g/day for men;
    Body mass index (18.5-24.9 kg/m2).

Women who met four of the five low-risk lifestyle factors lived 10 more years free of cancer, cardiovascular disease, and type 2 diabetes at 50 years than women who followed none of the low-risk factors. In men, the gain in disease-free life expectancy was near 8 years. In terms of total life expectancy, women in the low-risk group at age 50 showed an increase from 31.7 years to 41.1 and men increased their life span from 31.3 years to 39.4 years.

This large-scale study confirms what has been indicated by a host of earlier studies that healthy lifestyles involve proper diet, absence of smoking, low consumption of alcohol, substantial exercise, and a BMI in the range of 18.5-24.9 kg/m.2  Moreover, both women and men who have a healthy lifestyle have significantly more years in which they avoid crippling heart disease, cancer, and type 2 diabetes.

The largest impact was on reduced incidence of cardiovascular disease and diabetes in both women and men. The lifestyles that were most likely to increase the three major diseases were smoking and obesity, in both women and men. Perhaps beneficial effects would be magnified by more stringent healthy lifestyle criteria (for example, upper 10% of healthy diet or level of exercise).

Other posts on lifestyle and aging research have clearly identified other healthy factors, such as  the value of emotional well-being and reduced psychological stress. Anecdotes suggest that living a life of worthy purpose may also promote aging well and living longer, though apparently there is not much formal research on this possibility.

Though we have no direct control over our genes, most of us can largely control how we live our lives. The beneficial effects of healthy lifestyle on aging well and longevity surely include direct enhancement of organ function and indirect effects on gene expression. Healthy lifestyles will help you, as we say in Texas, "Go out with your boots on."

Source

Li, Yanping, et al. (2020). Healthy lifestyle and life expectancy free of cancer, cardiovascular disease, and type 2 diabetes: prospective cohort study, January 8, BMJ 2020; 368 doi: https://doi.org/10.1136/bmj.l6669

Saturday, March 17, 2018

Aerobic Exercise Makes You Smarter



On several occasions, I have written about the anti-aging beneficial effects of exercise. New studies, confirm earlier findings of exercise benefit. Now, a new study shows that exercise reduces levels of the major inflammatory chemical, interleukin-6, and an associated enhancement of neural activity in the brain circuitry used to encode information and form memories.
In response to earlier studies by others showing that exercise improves mental function, a team from mostly German universities studied the effects of exercise on 32 subjects aged 52 to 71 years old. They were particularly interested in memory because prior studies by others made it clear that age usually impairs memories of names and faces, situations and events, which are categorized as episodic memory. Tests of recall of episodic memory show marked age decrements in many subjects, even if they are given reminder cues.
Other researchers had shown that exercise, particularly aerobic exercise, reduces decline of episodic memory. This group of researchers wanted to explore why this benefit occurs. They examined two possibilities for the benefit of exercise:

1. Reduction of inflammatory chemicals (interleukin-6), which is known to occur with aerobic exercise in younger people, and
2. Strengthened connection among neurons that encode and form episodic memories (in the hippocampus, thalamus, and medial prefrontal cortex).

In the experiment on day one, subjects completed a survey that revealed each person's level of physical activity over the past week and gave a blood sample for measuring the baseline level of interleukin-6. Each subject then took several standardized tests of episodic memory. Then each subject had their brains scanned with fMRI while they were asked to memorize a series of faces and their association with a profession (pilot, electrician, bus driver, etc.). After the scan, they were tested for recall. The purpose of the scan was to assess functional connectivity, that is, how strongly the activation correlated in the brain areas that participate in encoding and memory formation.
The exercise survey allowed subjects to be grouped on the basis of aerobic and non-aerobic exercise during the prior week. The aerobic group remembered more items on the episodic memory task. The aerobic group also revealed stronger functional connectivity among several areas in the memory network. Additionally, there was a correlation with levels of the inflammatory chemical: subjects showing strong functional connectivity had the lowest levels of interleukin-6.
Limitations of the study include a failure to distinguish the intensity of exercise. For example, one can jog three hours a week at high speed or rather leisurely. Also, actual fitness of each subject was not measured, just a log of their exercise activities during the prior week. Another factor is that only one inflammatory chemical was studied. Interleukin-6 is one of a large family of such chemicals known as cytokines, and there are other inflammatory chemicals as well. Moreover, the significance of interleukin was not evaluated. When brain is damaged (by stress, metabolic production of free radicals, or whatever), interleukin-6 is released as a defense mechanism.
Nonetheless, a strong correlation, consistent with prior studies, was demonstrated between aerobic exercise, inflammation, and mental function. The authors did not speculate on why these effects occurred. I will.
Two contributing factors are obvious. One obvious factor is that aerobic exercise improves cardiovascular function and likely improves blood flow through the brain. The other obvious factor is that aerobic exercise releases the "feel-good" endorphins. Endorphins alleviate stress. Stress, more specifically the cortisol released during stress, shrinks the synaptic connections between neurons, which of course can be expected to diminish functional connectivity and information processing efficiency. Stress increases the level of inflammatory chemicals like interleukin-6. The low level of interleukin-6 in the aerobic group indicates that these brains were somewhat protected from the ravages of stress and free radicals.
Bottom line: aerobic exercise is good for older people. In addition to the well-known cardiovascular benefits, aerobic exercise makes people more sharp mentally. How one gets the needed aerobic exercise probably doesn't matter, as long as the exercise is sufficiently intense and sustained. Jogging, bike riding, swimming, and fast-moving sports should all prove beneficial.


Readers of this column will be interested in "Memory Medic's" e-book, Improve Your Memory for a Healthy Brain. Memory Is the Canary in Your Brain's Coal Mine (available in all formats from Smashwords.com). The book, devoted exclusively to memory issues in seniors, includes review of many of the ideas in these columns over the last five years.


Sources:

Thielen, Jan-Willem et al. (2016. Aerobic activity in the healthy elderly is associated with larger plasticity in memory related brain structures and lower system inflammation. Frontiers in Aging Neuroscience. 26 December. doi.: 10.3389/fnagi.2016.00319

Erta, M., Quintana, A., and Hidalgo, J. (2012) Interleukin-6, a Major Cytokine in the Central Nervous System. Int. J. Biol. Sci. 8(9):1254-1266. doi:10.7150/ijbs.4679. Available from http://www.ijbs.com/v08p1254.htm

Monday, March 05, 2018

Lifestyle Effects on Working Memory Ability

On multiple occasions, readers of my learning and memory blog posts asked me what they could do to improve their working memory. This is an important and very practical question. Working memory affects all aspects of life success: personal, educational, and professional. I usually tell them to practice attentiveness and concentration. But I probably should tell them to adapt a healthier lifestyle.

For over a decade a variety of studies have implicated lifestyle in memory function. A rigorous new study confirms these results. An Israeli research team studied 823 participants, aged 22-37 years, using brain scans taken during a difficult memory task, post-scan memory tests, and numerous measures of health and lifestyle. The brain scans identified the brain areas that particularly engage in working memory tasks, most important of which were the dorsolateral prefrontal cortex, parietal cortex, and anterior cingulate cortex. These then served as a frame of reference to check for correlations with health and lifestyle.

The key finding was a strong correlation between activity in working-memory brain areas and health and lifestyle. With all behavior/health variables considered together, the highest positive correlation occurred, in order, with fluid intelligence, reading, spatial orientation, picture vocabulary, several memory tests, and attentiveness.  

They observed an opposite correlation for such specific life-style indicators as large body mass index and a variety of unwise lifestyles such as binge drinking, and regular smoking. Health variables that correlated negatively with working-memory brain areas included high body-mass index, high blood pressure, poor glucose regulation.

The healthy lifestyle variables also correlated with other cognitive functions, such as fluid intelligence, reading/language skills, visuospatial orientation, sustained attention, mental flexibility and emotional intelligence, and physical endurance. Thus, the working memory benefit from healthy lifestyles seems to reflect a general improvement of brain function that good health confers.
The principle confirmed here supports the underlying theme of my recent e-book for seniors, which explained how memory serves a function like a canary in the coal mine. Memory decline is a warning signal of a damaged brain. That book explains the healthy life styles that people should be using as they age in order to keep the brain healthy and prevent memory deterioration. Changing lifestyle after the damage has already occurred may be too late. The point is that young people with healthy lifestyles have better brain function, and those lifestyles will help both body and brain to age well.
I recently published a book, “To Tell the Truth: Save Us from Concealment, Half-truths, Misrepresentation, Spin, and Fake News.” It is an inexpensive ($3.99), e-book now available at Amazon. At Smashwords.com you can choose among several e-book formats, including pdf.

Sources:

Klemm, W. R. (2014). Improve Your Memory for a Healthy Brain. Memory Is the Canary in Your Brain's Coal Mine. https://www.smashwords.com/books/view/496252


Moser, D. A. et al. (2017). An integrated brain-behavior model for working memory. Molecular Psychiatry. Doi: 10.1038/mp.2017.247

Thursday, July 25, 2013

Does Humor Make You Live Longer?

I just attended a “Laughter is Good Medicine” seminar put on by a local hospital. The speaker pointed to evidence showing that laughing has such good effects as:

·         Reduce blood pressure
·         Lower blood glucose
·         Dull pain
·         Alleviate stress and anxiety
·         Improve feeling of well being

and it even burns substantial calories.

I suspect humor also improves longevity, though I only have anecdotal and presumptive evidence for that. But the evidence seems hard to dismiss. Think about how long so many classic stand-up comedians of the
preceding generation lived.

Most of these comedians were actively performing right up to their last days. Here is a listing of comedians most people in my generation will recognize and their age when they finally died.

Bob Hope, 100
George Burns, 100
Phyllis Diller, 95
Milton Berle, 94
Henny Youngman, 92
Victor Borge, 91
Dick Van Dyke, 88 (still alive)
Jimmy Durante, 87
Jerry Lewis, 87 (still performing)
Bea Arthur, 87
Groucho Marx, 87
Jonathan Winters, 86
Jack Paar, 86
Red Skelton, 84
Bob Newhart, 84 (still performing)
Soupy Sales, 83
Rodney Dangerfield, 83
Mel Blanc, 81
Johnny Carson, 80
Jack Benny, 80


These comedians obviously had good memories, because even in their old age they could spout a steady stream of jokes from memory without a teleprompter. To have a good memory, you have to have a healthy brain, and a healthy brain often is healthy because the body is healthy. Healthy bodies live longer.

Let’s also remember that some of these people led a hard life, mostly on the road, in an era when people in general did not live that long.


One thing is for sure. Whether or not humor makes you live longer, it surely does make you live happier.