Somebody at Stanford University School of Medicine needs to get a hobby. Xiaotao Shen, a computational biologist, and Michael Snyder, a geneticist, co-wrote a study in which they sampled and tracked 135,000 types of microbes and molecules sourced from 108 adults aged 25 to 75 years old during a two-year period. The samples were taken from a healthy and ethnically diverse group of men and women at intervals of three to six months via nasal, oral and skin swabs plus blood and stool specimens.
Do the math. One hundred and eight people multiplied by 135,000 molecules and microbes including proteins, metabolites and RNA, times between four and eight test sessions per person, yielded 246 billion data points to analyze — an astounding amount of detail.
Based on scientific and medical understanding prior to this recent study most of us have believed that human aging was a long, gradual, and unfortunately downhill process. We begin to lose muscle mass in our 30s or 40s. We’re less able to store fluids in our bodies as we age, so our spinal discs shrink and lose elasticity which makes us shrink and lose elasticity too. Our nerves and brain can’t process information as quickly, and our sensory organs—sight, hearing, smell and taste—get worse over time. Wrinkles appear and our hair turns grey, and numerous invisible internal changes occur within our organs, tissue, and cells.
Our body has coping mechanisms to resist and adapt to these changes, but that too is a gradual process, and a battle which we ultimately lose. Various new technologies developed over the last two decades have allowed scientists to better understand which of the molecules we carry influence specific age-related diseases such as cardiovascular degeneration, kidney function, immune system deterioration, skin and muscle degradation and many others. From a preventative perspective though, understanding when to respond to age-related indicators with lifestyle or medication changes is not well understood.
Although Shen and Snyder would caution that their study was short-term and involved a limited number of participants, their findings indicate that there are two specific times in our life cycle that we experience a spurt, or increased amount of age-related molecular and microbiotic activity. Understanding when these spurts occur, and which specific microbes are involved, might help us time lifestyle or therapeutic interventions in the future.
They discovered that slightly more than 80 percent of the microbes and molecules they studied experienced more change, either increasing or decreasing in abundance and functionality, at two major life points: when a person is in their mid-40s, and when they are in their early 60s.
“We expected the changes in the 60s because this is when disease risk increases for nearly all diseases and people’s immune system decreases,” said Snyder, “but the changes in the 40s were unexpected.”
Similar changes were found in men and women, eliminating the impact of perimenopause or menopause.
Similar changes were found in men and women
Changes documented in our mid-40s included a significant difference in the molecules that allow us to metabolize fats (lipids), caffeine and alcohol—they lost their efficacy. The ability to drink multiple cups of coffee and still sleep soundly diminished, as did our liver’s ability to remove alcohol from our system. Lipid metabolism, the breakdown and storage of fats, is crucial to the creation and transport of energy, and the production of both good and bad cholesterol, cell membranes, and some hormones.
The great news is that by understanding the mid-life timing of these molecular shifts we can alter our lifestyles and diet, if necessary, to help counteract their negative consequences. This information has arrived much too late for me, but reducing coffee and alcohol intake during your 40s, and consuming good fats versus bad fats, represent a simple, non-medicinal opportunity to improve our long-term health and ageing outcomes.
The researchers noted that their study results showing the early 60s aging spurt reduced mental and physical functionality, and increased mortality risks, though certain cancers and cardiovascular issues need much more confirmation to be useful in improving healthy aging. However, by recognizing that carbohydrate metabolism decreases measurably in our early 60s we can consider non-medicinal lifestyle changes that may postpone morbidity.
Carbohydrates appear in three molecular groups: simple sugars such as glucose or sucrose; complex carbohydrates such as glycogen, starch and cellulose; and glycoconjugates, those molecules that attach to proteins or lipids and are important in limiting the risks noted in the paragraph above.
The American National Library of Medicine explains it succinctly: “Carbohydrates can either be catabolized for energy or used for anabolic functions such as the production of fatty acids.” Unsaturated fatty acids such as omega-3 help lower tryglicerides in our blood, reducing the chance of atherosclerosis, heart disease and stroke; while saturated fats and trans-fats are generally equated with weight gain, Type-2 diabetes, and increased cardiovascular risk
The choice is ours in both lifestyle and diet. Staying active in our early 60s and beyond will burn those carbs as energy; and eating carbohydrates that yield unsaturated fats rather than ingesting those containing saturated fats and trans-fats will ultimately improve our health after 60.
We’ve always known this instinctively, and now, thanks to Mr. Shen and Mr. Snyder, we have a better idea at what ages our best chance to act might occur.
