
New Scientist Magazine (October 7, 2023): This issue features ‘You And Your Microbiome’; How the microbiome changes our idea of what it means to be human; The best way to care for your microbiome to keep it healthy as you age; and more…

New Scientist Magazine (October 7, 2023): This issue features ‘You And Your Microbiome’; How the microbiome changes our idea of what it means to be human; The best way to care for your microbiome to keep it healthy as you age; and more…
Mexico City is the densely populated, high-altitude capital of Mexico. It’s known for its Templo Mayor (a 13th-century Aztec temple), the baroque Catedral Metropolitana de México of the Spanish conquistadors and the Palacio Nacional, which houses historic murals by Diego Rivera. All of these are situated in and around the Plaza de la Constitución, the massive main square also known as the Zócalo.

This poll examined older adults’ experiences with nine forms of everyday ageism. These forms were categorized into three groups: (1) exposure to ageist messages, (2) ageism in interpersonal interactions, and (3) internalized ageism (personally held beliefs
about aging and older people).

Eat less, live longer- If you want to reduce levels of inflammation throughout your body, delay the onset of age-related diseases and live longer—eat less food. That’s the conclusion of a new study by scientists from the US and China that provides the most detailed report to date of the cellular effects of a calorie-restricted diet in rats.
(Salk News, February 27, 2020)
While the benefits of caloric restriction have long been known, the new results show how this restriction can protect against aging in cellular pathways, as detailed in Cell on February 27, 2020.
Aging is the highest risk factor for many human diseases, including cancer, dementia, diabetes and metabolic syndrome. Caloric restriction has been shown in animal models to be one of the most effective interventions against these age-related diseases. And although researchers know that individual cells undergo many changes as an organism ages, they have not known how caloric restriction might influence these changes.
In the new paper, Belmonte and his collaborators—including three alumni of his Salk lab who are now professors running their own research programs in China—compared rats who ate 30 percent fewer calories with rats on normal diets. The animals’ diets were controlled from age 18 months through 27 months. (In humans, this would be roughly equivalent to someone following a calorie-restricted diet from age 50 through 70.)
A slight uptick in U.S. life expectancy in the U.S. in 2018 was due partly to a decrease in overdose deaths, but mostly to decreasing cancer deaths.
From a JAMA Network Open online release (February 21, 2020):
Across the 6 studies of 8699 participants, mean age ranged between 70 and 74 years and mean gait speed ranged between 1.05 and 1.26 m/s. Incident dementia ranged from 5 to 21 per 1000 person-years. Compared with usual agers, participants with only memory decline had 2.2 to 4.6 times higher risk for developing dementia…
Those with only gait decline had 2.1 to 3.6 times higher risk. Those with dual decline had 5.2 to 11.7 times the risk…
Impaired mobility, such as slow gait, is associated with an increased risk of dementia, but the effect size of this association is generally modest.1–6 Identifying persons who experience both mobility decline and memory decline, a main symptom in the early stage of dementia, may have a greater prognostic value in assessing risk of dementia because the combination could identify a group in whom gait speed decline is at least in part caused by neurodegenerative pathologic conditions of the central nervous system rather than local musculoskeletal problems, such as sarcopenia or osteoarthritis.7–9 A recent study of 154 participants with mild cognitive impairment reported that those who declined in both cognition and gait speed had the highest risk of dementia.
From BMJ Journal “Gut” study (February 17, 2020):
We observed that increased adherence to the MedDiet modulates specific components of the gut microbiota that were associated with a reduction in risk of frailty, improved cognitive function and reduced inflammatory status.
Objective Ageing is accompanied by deterioration of multiple bodily functions and inflammation, which collectively contribute to frailty. We and others have shown that frailty co-varies with alterations in the gut microbiota in a manner accelerated by consumption of a restricted diversity diet. The Mediterranean diet (MedDiet) is associated with health. In the NU-AGE project, we investigated if a 1-year MedDiet intervention could alter the gut microbiota and reduce frailty.
Design We profiled the gut microbiota in 612 non-frail or pre-frail subjects across five European countries (UK, France, Netherlands, Italy and Poland) before and after the administration of a 12-month long MedDiet intervention tailored to elderly subjects (NU-AGE diet).
Results Adherence to the diet was associated with specific microbiome alterations. Taxa enriched by adherence to the diet were positively associated with several markers of lower frailty and improved cognitive function, and negatively associated with inflammatory markers including C-reactive protein and interleukin-17. Analysis of the inferred microbial metabolite profiles indicated that the diet-modulated microbiome change was associated with an increase in short/branch chained fatty acid production and lower production of secondary bile acids, p-cresols, ethanol and carbon dioxide. Microbiome ecosystem network analysis showed that the bacterial taxa that responded positively to the MedDiet intervention occupy keystone interaction positions, whereas frailty-associated taxa are peripheral in the networks.
Conclusion Collectively, our findings support the feasibility of improving the habitual diet to modulate the gut microbiota which in turn has the potential to promote healthier ageing.