Diet, Aging, and Longevity

 

Contents Aging and longevity factors Psychological factors in aging and longevity Character values and traits in aging

Longitudinal studies on aging & longevity Idiosyncrasies of centenarians The blue zones: the 9 lessons The gut microbiota and longevity

Aging and longevity has been the concern of people since ancient times. From biblical scriptures, references are made to the medicinal properties of food and herbs. Representing health and longevity from God, the importance of diet and of preparing and eating food was regarded as a spiritual act. To that end, the Israelites adhered to the teaching of the Torah: the kosher laws. Though an ancillary hygienic benefit is attributed to the observance of kosher laws, it's purpose was also the health benefit of keeping kosher. For instance, eating kosher is said to have physical benefits, such as improving the digestive system and lowering the risk of certain diseases. According to Jewish scholars, keeping kosher is also beneficial because it can lead to a healthier lifestyle.

Other religions also prescribe a set of dietary guidelines for its believers to follow. Islamic dietary laws are said to be in the interest of health and cleanliness, and in obedience to the rules of Allah. Muslims are allowed to eat what is "good" — that is, food and drink identified as pure, clean, wholesome, nourishing and pleasing to the taste. In general, everything is allowed (Halal) except what has been forbidden, such as alcohol. Buddhism also has specific dietary rules that followers to practice. Most Buddhists follow a lacto-vegetarian diet. It is noted that there are practicing Buddhists, Taoists and Daoists in Asian countries who consume food and herbs for good health. It is also believed that food has medicinal properties (e.g., ginseng).

Aging and longevity factors

A questionnaire was developed to include items that would help determine the idiosyncrasies of individuals who have reached the age of 70 and beyond. Participants had to visualize waking up in the distant future, after retirement, and, being 'on the same path they were now', and imagine how their mind and outlook would feel, and what their body would be telling them.

The questionnaire included demographic questions, such as age and income. It also contained items designed to assess individual's characteristics, as well as scaling questions, such as information on Nutrition (e.g., How often do you eat vegetables?); Physical Activity (e.g., Do you exercise three or more times per week?); attitude to Old Age (e.g., Should retired people put their wisdom to work for the benefit of society?); Family (e.g., Do you have a satisfying relationship with your spouse?); Relationships (e.g., Do you have a social network that provides social and emotional support in times of need?); A sense of purpose (e.g., Are you using your skills on activities that you feel passionate about in an environment that gives you a voice and in which your values and dignity are honoured).

A factor analysis was conducted on the data to determine the underlying factors contributing most to aging and longevity. The results revealed that the factors derived from the analyses were consistent with the conceptual basis of the longevity questionnaire. Subsequent analyses revealed marked stability of the factor structure.

Results show that good health and aging well relate to a lifestyle that includes a diverse diet, exercise, sleep, stress management and a positive attitude towards aging. This lifestyle is fundamental to health and longevity, as for most things. Income is also related to health and longevity, simply because money allows us to have access to proper housing, health services, transportation, and quality food. Family is highly important for healthy living and a long-life. Interestingly, many respondents had parents who had passed away in their mid-eighties and nineties+. The education they received from their parents and community was to be passed on to future generations. They owed it to themselves, and their children to make that positive change to inspire others. Regarding relationships, they believed you should surround yourself with people who have similar beliefs and goals. People whose friends share similar values and who have conversations about what is important to them get more positive results, and are healthier and live longer.

Psychological factors in aging and longevity

For most respondents, longevity starts with the mind, as does health, wealth, success, and everything else. This is BECAUSE everything we do, who we become, and what we think, is the result of what we have CHOSEN to put in our Mind, in our Body, and in our Life. The belief is that there are benefits to a long healthy life. For those who are baby boomers, Gen X, or Millennial (Gen Y), life is something to embrace, to be used for good, and worth prolonging, in good health. Their philosophy is that when the body is healthy, we are happier, wealthier, and wiser. Importantly, this leads to higher cognitive abilities that foster continuous learning. To that end, engaging in positive self-talk is also helpful, as is putting time aside for play, relaxation, and fun.

The environment is also connected with aging well and longevity; in particular, the climate, clean air and water, as well as good housing and neighbourhoods. A man said once that he was lucky to reside on lake Ontario, at the east-end of lake Erie. "I have a cozy home and plenty of fresh air coming from the south-west," he said, "in addition to access to major roads and most services. There are immense warehouses right next to the grocery store where I shop, where food is delivered three times a week as opposed to once a week to other stores." He went on to say that he was surprised to notice that not long ago the vegetable and fruit section had expanded. "I get all kinds of greens during the winter months: leeks, Swiss chard, dragon fruit, strawberries and blueberries, mandarins, and you name it, they have it."

Character values and traits in aging

Specific character traits and values (e.g. honesty and trust) were linked with successful aging. Most respondents cited specific traits and values as important to a long healthy life. These traits or attributes were learned in faith groups and/or schools. For instance, a respondent recounted having learned them in the primary grades: he had them listed under the acronym R.R.I.C.C.H: Respect, Responsibility, Inclusiveness, Cooperation, Caring, and Honesty. Most school boards across North America, if not all, teach students character traits and values (e.g., Respect for Self and Others, Trustworthiness, Compassion). To school administrators, and teachers, Character Education helps students improve their learning and social skills, and improve their physical and mental wellness. As well, these values increase empathy, feelings of safety and inclusion.

The hundreds or so character traits and values are universal traits that foster self-harmony and the harmony of people living together. These values transcend culture and have been the focus of groups, organizations, and civilizations throughout the ages. Individuals' character attributes are used to match people with certain types of jobs and to improve performance in industrial settings. Universal character traits empower individuals in the pursuit of a long lasting career. It may well be that successful aging results from specific sets of character traits and values. These would help individuals shape their environment, which would require specific skills, and have goals leading to positive outcomes related to well-being, health, and longevity (Lang & Rohr, 2015). 

Longitudinal studies on aging & longevity

The factors that contribute to aging and longevity have been researched with longitudinal studies; i.e., long-term studies involving the collection of economic, social, psychological, health, as well as biological and genetic data. Findings show that longevity is increased by positive self-perceptions of aging. Having a positive outlook on aging impacts on other factors associated with longevity, including health, wealth, and social well-being. Long-term research has also found that marital satisfaction has a protective effect on people’s mental health and that tending to our relationships (family and friends) also keeps people happy throughout their lives. Individuals who had unhappy marriages felt both more emotional and physical pain. Moreover, individuals who lived longer and enjoyed sound health avoided alcohol. Researchers also found that those with strong social support experienced less mental deterioration as they aged.

In a book called “Aging Well,” that highlights findings from the Harvard Study of Adult Development (2003), George Vaillant wrote that six factors measured by age 50 predicted healthy aging in men: physical activity, absence of alcohol abuse and smoking, having mature mechanisms to cope with life’s ups and downs, and enjoying both a healthy weight and a stable marriage. For the inner-city men, education was an additional factor. “The more education the inner city men obtained,” wrote Vaillant, “the more likely they were to eat sensibly, and use alcohol in moderation. Vaillant’s research highlighted the role of these protective factors in healthy aging. The more factors the subjects had in place, the better the odds for longer, happier lives.

There is currently a number of longitudinal studies investigating the factors that impact on aging and longevity. For instance, the Longitudinal Study of Aging (NILS-LSA), the English Longitudinal Study of Ageing (ELSA), and the Chinese Longitudinal Healthy Longevity Survey (CLHLS), have generated some data published in science journals. These longevity studies have large set of factors that include psychological as well as biological and genetic data with promising results to enlighten our understanding of the aging process and longevity. It is hoped that these long-term studies' results will support the enhancement of programs, services, and policies for greater health among world populations. The McKinsey Global Institute ( 2020 report) cited that a country's greatest asset is it's population's health, which, along with the advancement in science and technology, represents a major determinant of a country's progress, wealth, and prosperity.

Idiosyncrasies of centenarians

There are more centenarians living today than ever before. Among them is Jeanne Louise Calment, a French centenarian with a lifespan of 122 years. Marie-Louise Meilleur, also a centenarian, was born in Kamouraska, Quebec. She married twice. Out of her twelve children, four survived her. She had 85 grandchildren, 80 great-grandchildren, 57 great-great-grandchildren, and four great-great-great-grandchildren. Among men, we have Gustav Gerneth. According to a statement by his granddaughter on his 113th birthday, he still had a lucid mind, was watching football, solving crosswords, and doing mental arithmetic. Asked for the reason for his long life, he said, "I have always been living and eating well. No diet. Always butter, never margarine. I have not touched any cigarette my whole life and I drink alcohol only at celebrations."

Then, we have learned of Mrs. Joanne Baker's life. A vibrant lady then in her eighties, Mrs. Baker was adopted shortly after birth by an upper-middle-class family that served her well. The family's financial means allowed her and her siblings (step brother and step sister) to enrol in higher education that was followed by a brilliant career. Surprisingly, Mrs. Baker learned that she had an identical twin sister, Marie, who was adopted by a lower-income family. Mrs. Baker's sister dropped out of high school, married, had two children, divorced, and became a single mother. Marie struggled with bouts of depression.

Mrs. Baker and Marie's psychological profiles were very different. Joanne was a optimist while Marie behaved more like a recluse. We heard of Mrs. Baker again when she turned 100. At the wedding of one of her great-grandsons, she told the guests about a letter she received from the President, congratulating her on achieving her 100th birthday. Mrs. Baker had all the characteristics of people who live to be healthy centenarians. She had a positive outlook on life, ways of enriching her mind, and a willingness to share positive vibes with others. She believed in the culture of Health, Prosperity, and Longevity. Unfortunately, her sister, Marie, was the opposite. In her eighties, crippled with chronic disease, she said: 'If I have to live like this, I'd rather die."

The blue zones: the 9 lessons

Dan Buettner (2005), a researcher of longevity, wrote a cover story for National Geographic titled “The Secrets of a Long Life.” In 2008 he wrote a book titled The Blue Zones in which he explored the places in the world where a higher percentage of people enjoy a long and healthy life. His goal was to define the diets, eating habits, and lifestyle practices associated with longevity. Because the western diet and lifestyle was not the most suitable for such a project, Buettner asked himself the question: What program could help an individual have a long, healthy, prosperous life, and, more particularly, help a person be happy, lose weight, maximize mental sharpness, and keep working as long as possible? There are five world regions that Buettner researched: Sardinia, Italy, the islands of Okinawa, Japan; the Seventh-day Adventist community of Loma Linda, California; Nicoya Peninsula, Costa Rica; and the island of Icaria in Greece.

Buettner's experiences with the centenarians of the Blue Zones led him to formulate Nine Lessons for Living Longer. What he discovered was that healthy living and longevity is a lifestyle that puts family and social circles first. The world's longest-lived people have strong family connections (with spouses, parents, grandparents and grandchildren) as well as close friends and strong social networks. People in the Blue Zones are active (with work and hobbies) and have a purpose in life; knowing what to do when they get up in the morning makes them healthier and happier. The diet is the cornerstone of most centenarians' lifestyle, consisting of vegetables, fruit, and whole grains with some dairy and meat eaten in small amounts. Of importance is the chewing of the food, eaten slowly, and stopping before the stomach is full. As well, except for the Adventists, wine is consumed with food and in the company of friends. Stress is part of life which the centenarians manage through stress-relieving rituals: a time to play and a time to pray is incorporated into their daily routine.

Buettner has implemented Blue Zones Projects in partnership with municipal government, corporations and health insurance companies. Blue Zones Projects are wellness initiatives that apply lessons learned from the Blue Zones to entire communities by focusing on changes, not only to food choice, but also to policies that optimize the city environment for health (e.g., sidewalks and bike paths, financial security, and affordable health care) so as to reap the benefits of the Blue Zones (see Buettner, 2017).

The gut microbiota and longevity

The gut microbiota was recently implicated in healthy aging and longevity (Badal et al., 2020; Biagi et al., 2017; Kim, B.-S. 2019; Salazar et al., 2019)). Indeed, Bian's et al. study (2017) from the China Institute analyzed gut bacteria from more than 1000 healthy Chinese participants ranging in age from 3 to over 100,and found that a healthy gut is a key indicator of individuals who live past the age of 100. The main conclusion of the study is that at age 90, microbiota had changed little from that of a healthy 30-year-old. The authors go on to say that it is the diversity of the gut microbiota that remained much the same throughout their study group, which finding is taken to indicate that maintaining diversity of the gut as one ages is a biomarker of healthy aging.

On the other hand, Wilmanski's et al. (2021) research data from over 9,000 people found a unique pattern of the microbiome's bacteria - starting in mid-life - 40-50 years old - was associated with healthy aging and longevity in the later decades. As well, the authors reported that the adult's gut microbiota continues to develop with advanced age in healthy individuals. For instance, fecal samples collected from centenarians showed a relative abundance of some bacteria to be considerably higher in subjects from a 'longevity village' than those from urbanized towns. This finding has clinical implications for monitoring and modifying gut microbiome health throughout a person's life.

Let us recall that John F. Cryan's research on the gut-brain interaction reported that a treatment for chronic diseases is likely to be, in the future, the administration of specific sets of gut microbes (Cryan & O'Mahony, 2011 Sherwin, Dinan & Cryan, 2017). However, other research such as that of Low et al. (2021), Sala et al. (2020) and Wilmanski's findings indicate that a unique set bacteria will not only be diagnostic of healthy aging, but it can help treat chronic diseases as well as prolong one's life span.

Let us point out that the metabolic processes of the gut microbiome are involved with regulating major aspects of the immune system, the nervous system as well as the hormonal (endocrine) system. In addition, a number of studies have indicated that an unhealthy diet causes damage to these systems' organs, failing to protect an individual against organ-related illnesses. Of importance is the fact that viral and bacterial infections (encephalitis, rheumatic fevers, tonsillitis) cause problems similar to those of unhealthy diets. However, a healthy diet protects individuals against age-related diseases, which are inflammation-based, such as arthritis, heart disease, and diabetes.

Overall, the studies that predict health, aging and longevity point to several factors. The two strongest predictors that correlate most with healthy aging, is diet, and one's attitude towards aging. There are ways one can prepare for a long healthy and happy life. What's good is that several factors are within our control. There's a great lesson learned in the story of Mrs. Baker and her sister Marie. Even though people may share identical genes, factors such as family role models, socioeconomic status, and education can rob a person's opportunity for a long, healthy, prosperous life. One thing that we can agree upon is that being aware of the factors associated with longevity and aging well, can help us have a longer, healthier, and more prosperous life.

References

Badal, V. D., Vaccariello, E. D., Murray, E. R., Yu, K. E., Knight, R., Jeste, D. V., & Nguyen, T. T.  (2020). The Gut Microbiome, Aging, and Longevity: A Systematic Review. Nutrients, 12(12), 3769. https://doi:10.3390/nu12123759

Biagi, E., Rampelli, S. Turroni, S., Quercia, S., Candela, M., & Brigidi, P. (2017). The gut microbiota of centenarians: Signatures of longevity in the gut microbiota profile. Mechanisms of Ageing and Development, 165, 180-184. https://doi.org/10.1016/j.mad.2016.12.013

Bian, G., Gloor, G. B., Gong, A. et al. The gut microbiata of healthy aged Chinese is similar to that of the healthy young. mSphere, 2(5). https://doi:10.1128/mSphere.00327-17

Buettner, D. (2008). The blue zones: 9 lessons for living longer. National Geographic,

Buettner, D. (2010). Thrive: Finding happiness the Blue Zones way. National Geographic,

Buettner, D. (2017). The Blue Zones of Happiness: A Blueprint for a Better Life.: National Geographic,

Cryan, J. F., & O'Mahony, S. M. (2011). The microbiome-gut-brain axis: From bowel to behavior. Neurogastroenterology and Motility, 23(3) 187-192. https:// doi:10.1111/j.1365-2982.2010.01664.x

Kim, G.-S., Choi, C. W., Shin, H., et al. (2019). Comparison of the Gut Microbiota of Centenarians in Longevity Villages of South Korea with Those of Other Age Groups. Journal of Microbiology and Biotechnology, 29(3): 429-440. https://doi.org/10.4014/jmb.1811.11023

Lang, F. R., & Rohr, M. K. (2015). Successful Aging in Societies of Long Living: The Model of Selection, Optimization, and Compensation. In J. Wright (ed.). International Encyclopedia of the Social and Behavioral Sciences (2nd ed., pp. 667-672). Oxford, UK: Elsevier. https://doi:10.1016/B978-0-08-097086-8.26095-9

Low, D. Y., Hejndorf, S., Tharmabala, R. T., Poppena, S., & Pettersson, S. (2021). Regional Diets Targeting Gut Microbial Dynamics to Support Prolonged Health span. Frontiers in Microbiology, 23(3), 197-192. https://doi.org/10.3389/fmicb.2021.659465

McKinsey Global Institute. (July 8, 2020) Prioritizing health: A prescription for prosperity. Report

Sala, C., Giampieri, E., Vitali, S. et al., (2020). Gut microbiota ecology: Biodiversity estimated from hybrid neutral-niche model increases with health status and aging. 10,1371/Journal.pone.0237207. https://doi.org/10.1371/journal.pone.0237207

Salazar, N., Arboleya, S. Fernández-Navarro, T., de los Reyes-Gavilán, C. G., Gonzalez, S., & Gueimonde, M. (2019). Age-related changes in gut-microbiota and dietary related with the immune system in adulthood and old age: A cross sectional study. Nutrients, 11(8), 1765. https://doi:10.3390/nu11081765

Sherwin, E., Dinan, T. G., & Cryan J. F. (2017). Recent developments in understanding the role of the gut microbiota in brain health and disease. Annals of the New York Academy of Sciences, 1420 (1), 5-25. https://doi.org/10.1111/nyas.13416

Vaillant, G. E. (2003). Aging Well: Surprising Guideposts to a Happier Life from the Landmark Harvard Study of Adult Development. Little, Brown Spark.

Wilmanski, T., Diener, C., Rappaport, N., et al, (2021). Gut microbiome pattern reflects healthy ageing and predicts survival in humans. Nature Metabolism, 3(2), 274-286. https://doi.org/10.1038/s42255-021-00348-0