Longevity Then and Now
It is now generally accepted that aging is plastic and that how we age is becoming more and more under our control. Many people believe that this is due to things such as better hygiene (personally and socially), better medicine, and even safer work conditions. And, while these reasons are valid and true for increasing our life expectancy, they are not factors for extending human longevity, they merely eliminate many of the death inducing things that we have faced on the road to old age.
"80% of all deaths are lifestyle related"
Longevity and The Adventure Life
Our bodies evolved over millions of years to walk and run over long distances, to lift things, climb things, and most importantly, to throw things. We’ve even retained the ability to swing from things (somewhat) as a bonus. Evolution says that what doesn’t hold you back, doesn’t get lost. Don’t quote me on that. We are the most physically well-adapted creatures on the planet (humans would easily defeat any other creature in a intraspecies decathlon). Yet most of us (and the number is growing), are content to let this supercharged vessel, with all of this “god-given” athleticism just sit idle on the couch of life (trademark pending).
Some may argue that this is exactly what we evolved into. That this is what evolution does. We tamed our surroundings, we controlled nature (somewhat), and we created a much easier, or predictable way to survive and prosper. This I can’t argue with, but I would say that in the process, we have found newer and more devious ways to take years off our lives. I would argue that these are better years as well.
Some may argue that this is exactly what we evolved into. That this is what evolution does. We tamed our surroundings, we controlled nature (somewhat), and we created a much easier, or predictable way to survive and prosper. This I can’t argue with, but I would say that in the process, we have found newer and more devious ways to take years off our lives. I would argue that these are better years as well.
"The baby boom generation is the first in centuries that has actually turned out to be less healthy than their parents, thanks largely to diabetes, poor diet, and general physical laziness."
The most important factor in longevity is lifestyle.
What Happens When We Age
When we are born our bodies convert mass amounts of energy into incredible growth levels, puberty brings on a flood of hormones triggering that final growth push into adulthood, a leveling off during our child-producing years, then in our 40’s things start to go awry. We begin losing bone density and muscle mass. Our cardiorespiratory capacity starts to diminish, as well as our balance and walk/run pace.
It is very important to note that unchecked growth is not something we would want to have occurring within us - this could/would lead to cancer, but idle growth would/could lead to frailty which is not ideal either. Balance is what we seek (a recurring theme).
Side note - When we have our blood chemistry tested and we research the results a little bit, we will notice that having too high or too low a number in any category is rarely ideal. These numbers are measures of something that is going on inside us. Too much of something means our body is reacting to something, too little and it means something is restricting its production. What we hope to see are numbers right in the middle of the extremes.
Change in Fat StorageIt is very important to note that unchecked growth is not something we would want to have occurring within us - this could/would lead to cancer, but idle growth would/could lead to frailty which is not ideal either. Balance is what we seek (a recurring theme).
Side note - When we have our blood chemistry tested and we research the results a little bit, we will notice that having too high or too low a number in any category is rarely ideal. These numbers are measures of something that is going on inside us. Too much of something means our body is reacting to something, too little and it means something is restricting its production. What we hope to see are numbers right in the middle of the extremes.
The areas of fat storage transition from subcutaneous (near the body’s surface under the skin) to visceral (deeper inside us and around our organs). Visceral fat is strongly linked to metabolic disease and insulin resistance, and an increased risk of death, even for people who have a normal body mass index. Subcutaneous fat doesn't carry the same risks -- some subcutaneous fat may even be protective.
Read - Visceral Fat vs. Subcutaneous Fat (coming soon)
Decreased Bone Density
Most cells within the human body have there own life cycle. A cell is born, it does its required job, and then after a somewhat predetermined amount of time, it dies (or more accurately, it is recycled). The cells that make up the bones of our skeletal system are no different. Inside the bone “tissue” homeostasis is maintained where some cells build new bone tissue, others dissolve bone and release the minerals inside. But as we get older, we begin to lose more bone than we build, making our bones less dense (weaker) which leads to osteoporosis.
It is this weakness in the bone tissue that leads to an increase in broken bones mostly due to some kind of weight-bearing impact usually caused by a fall. This type of accident can be debilitating and if severe enough (hip fracture) even life-changing.
Calcium is the mineral that gives bone its strength. It can come from the foods you eat—including milk and milk products, dark green leafy vegetables like kale and collard greens—or from dietary supplements. Women over age 50 need 1,200 mg of calcium a day. Men need 1,000 mg a day from ages 51 to 70 and 1,200 mg a day after that.
Vitamin D helps your body absorb calcium. As you grow older, your body needs more vitamin D, which is made by your skin when you’re in the sun. You can also get vitamin D from dietary supplements and from certain foods, such as milk, eggs, fatty fish, and fortified cereals. Bone tissue, just like muscle tissue, responds to stress by activating the cellular growth phase to compensate for the “damage” that has been done. Weight bearing exercise is a great way, maybe the only way, for us to stimulate/encourage this process. It’s not just the impact on the bone, say from running, but the pulling of the muscle n the bone that it is attached to that provides stress as well.
Decreased Muscle Mass
Sarcopenia is the loss of muscle mass due to aging. From birth until about the age of 30, our muscles are in the growth phase, but sometime in our 30’s our muscles stop growing and we begin to lose muscle mass. Physically inactive people can lose as much as 3% to 5% of their muscle mass each decade after age 30. Even if you are active, you’ll still have some muscle loss.
Here are some factors in the development of sarcopenia:
- Reduction in nerve cells responsible for sending signals from the brain to the muscles to start movement.
- Lower concentrations of some hormones, including growth hormone, testosterone, and insulin-like growth factor
- A decrease in the ability to turn protein into energy
- Not getting enough calories or protein each day to sustain muscle mass.
Just like bone tissue, muscle tissue responds to stress via activation of cellular regrowth that repairs damaged tissue and even builds new tissue if the stress was adequate enough.
By creating our own “stressful” events through training and exercise, we can build new muscle tissue at a rate that can counteract or even outpace the process of sarcopenia well into “old age” and even to the very day we die. Exercise and more importantly, strength training are the only forms of treatment for sarcopenia.
Loss of bone density and muscle mass will not only lead to frailty it is frailty and will be the cause of our physical decline and even our early exit. Sarcopenia is not just a possibility or even a probability that comes with aging, it is guaranteed, but it is also something that we have 100% control over the outcome. Ok, maybe 90%.
Change in Hormone Production
There are so many hormones produced by the endocrine system related to aging that detailing them all would go way beyond the scope of this section, but there are a few that are so important that it is worth taking a look.
Testosterone - a major regulator sex drive, bone mass, fat distribution, muscle mass and strength, and in males, sperm production. For men ages 19 and up, normal testosterone levels range from 300 to 1200 nanograms per deciliter (ng/dL). For women ages 19 and up, normal testosterone levels range from 8 to 60 ng/dL.
Testosterone levels reach their peak around age 18 or 19 before declining throughout the remainder of adulthood. As men get older, their testosterone levels may decline about 1 percent per year after age 30. By the age of 80, a man’s testosterone level may only be 20% of what it was in his youth. In premenopausal women, testosterone is made mainly in the ovaries. Levels will decline after menopause, which usually begins between ages 45 and 55.
When testosterone levels are too low, men may experience less interest in sex, fewer spontaneous erections, and a reduced intensity of orgasm and sensation. It may also cause loss of pubic hair, decrease in energy, increase in fatigue, depression, poor concentration and memory, disrupted sleep, and reduced strength.
Strength building through resistance training has been shown to positively affect testosterone levels in men and women, but these effects seem to diminish as we age. While the increase is not significant, it does appear that the lack of increase is due to the body’s desire for homeostasis and not for a lack of benefit.
Human Growth Hormone - a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. GH is a stress hormone that stimulates production of IGF-1 and raises the concentration of glucose and free fatty acids. Some of the effects of HGH on the body include:
- Increases calcium retention,[citation needed] and strengthens and increases the mineralization of bone
- Increases muscle mass through sarcomere hypertrophy
- Promotes lipolysis
- Increases protein synthesis
- Stimulates the growth of all internal organs excluding the brain
- Appears to improve cognitive function
While the superficial effects of HGH can attained via external acquisition (by prescription), there are substantiated negative side-effects, such as an increased risk of cancer, and the long-term effects on aging appear to be nullified due to an associated increase in IGF-1 levels.
Insulin - Insulin is produced by the pancreas. It helps sugar (glucose) go from the blood to the inside of cells, where it can be used for energy and converts the excess to fat. The average fasting glucose level rises 6 to 14 milligrams per deciliter (mg/dL) every 10 years after age 50 as the cells become less sensitive to the effects of insulin.
Cortisol - the "stress response" hormone. It affects the breakdown of glucose, protein, and fat, and it has anti-inflammatory and anti-allergy effects.
IGF-1(insulin-like growth factor 1) - an endocrine hormone produced mainly in the liver, who’s production is induced by growth hormone (GH) and can be retarded by undernutrition. IGF-1 stimulates systemic body growth, and has growth-promoting effects on almost every cell in the body, especially skeletal muscle, cartilage, bone, liver, kidney, nerve, skin, hematopoietic, and lung cells. In addition to the insulin-like effects, IGF-1 can also regulate cellular DNA synthesis. Findings demonstrate that increased circulating IGF-1 reduces systemic and vascular oxidant stress and decreases atherosclerosis progression. IGF-1 is positively regulated by specific nutrients such as selenium, zinc, magnesium, along with energy and protein intake.
More on IGF-1 (coming soon)
Our Metabolism Slows Down
Your metabolism comprises all of the chemical reactions that help keep your body alive. Resting metabolic rate, thermic effect of food, and exercise and non-exercise activity thermogenesis all determine your metabolic rate. Multiple studies on aging and metabolism have shown that:
- Regular endurance exercise prevents a slowing of the metabolism
- An increase in muscle mass correlates with an increase in metabolism
- Less mitochondria at the cellular level equates with a slower metabolism
However, after accounting for differences in gender, muscle and fat, scientists found that the people aged 60–74 burned only 24 fewer calories, while those over 90 burned 53 fewer calories on average daily.
Research shows that maintaining muscle mass and activity levels have the greatest positive effect on our metabolism (2, 3).
Reduced Cardiorespiratory Capacity
Our cardiorespiratory capacity is our ability to take in oxygen via the lungs, move it to the muscular system and exchange it for CO2 via the cardiovascular system, and the CO2 to the lungs for expulsion. There are multiple processes which take place throughout this cycle, and the efficiency of each of these processes is what determines our overall capacity. This capacity is measured as our our VO2 Max and it is witnessed to steadily decline after the age of 30 (Study).
It has also been shown that cardiorespiratory training of older men and women is effective in increasing VO2max and results in the usual changes during submaximal exercise. These benefits of cardiorespiratory training are substantial in that the increases observed compensate for the losses with ageing described over the period of a decade or more.
Degradation of Skin Health
As we age, one of the most obvious and possibly least controllable changes that we experience is the deterioration of our skin. Here are some changes we must endure:
- The outer layer, the epidermis, becomes thinner.
- Changes in the connective tissue reduce the skin's strength and elasticity.
- The blood vessels of the dermis become more fragile leading to bruising and bleeding under the skin.
- Sebaceous glands produce less oil as you age.
- The subcutaneous fat layer thins so it has less insulation and padding, reducing our ability to maintain body temperature.
- The sweat glands produce less sweat, making it harder to keep cool.
All of this contributes to the declining functionality of such a valuable organ. The results of this process are all too apparent as we look in the mirror and notice a new wrinkle or a grey hair. This is aging in action. Or is it?
As with all of the processes of “aging”, what if it is the other way around? What if it’s the degradation of our skin and its inability to do its job that affects the rate of aging? If these side-effects of aging are actually the causes, then what if we did everything we could to reduce or eliminate them. Could reducing or eliminating these causes slow down the skin’s degradation and in the process slow down aging? It is definitely plausible that the health of our skin can directly impact our lifespan.
And if not it is highly probable that protecting and nourishing our skin will definitely affect our healthspan, and if nothing else, it will give us great skin as we drive deeper into “old age”.
Digging deeper - The Health of Our Skin (coming soon)
Running The Gauntlet
The numbers that are used to define life expectancy (the expected lifespan) can be very misleading. If we compare our life expectancy of 48 in 1900 with 82 in 2013, we see an incredible growth in our lifespans. But if we look at the life expectancy of a 50 year old of 71 versus 82 respectively, our life expectancy has improved nearly as much. And comparing that of 70 year olds, 78 versus 84, the difference is even less. By far, the main reason for this difference in life expectancy gains is due to a vast improvement in fighting infectious diseases, whose main victims are newborns and infants.
In 1900, if you made it to age 10, you were well on your way to a long life. Basically, by eradicating diseases such as pneumonia and tuberculosis, we all but removed the first major hurdle to old age. But interestingly, as more and more people were making it to adulthood, we start seeing a drastic rise in non-infectious diseases like heart disease and cancer.
If we are able to get through cancer and heart disease, we have to face diabetes and eventually there is a wall toward the end called Alzheimer’s Disease. This can all sound a bit daunting and may even lead us to feel that we are not up for this constant battle, but the truth is that each and every hurdle we face through the gauntlet of aging is either somewhat or entirely under our control.
In fact there are only two causes of death (unintentional injury #3 and Septicemia #11) in the top 12. But death by unintentional injury (unintentional falls, traffic deaths, and unintentional poisoning deaths) can be greatly reduced by driving more carefully, strengthening our core, and avoiding drinking suspect chemicals. So, Septicemia (the result of a bacterial infection in the bloodstream) is the only one that we have no control over.
By doing all the right things we can overcome the obstacles that life throws at us, destroy the gauntlet, and enjoy every minute of it. Unless we get Septicemia.
In 1900, if you made it to age 10, you were well on your way to a long life. Basically, by eradicating diseases such as pneumonia and tuberculosis, we all but removed the first major hurdle to old age. But interestingly, as more and more people were making it to adulthood, we start seeing a drastic rise in non-infectious diseases like heart disease and cancer.
If we are able to get through cancer and heart disease, we have to face diabetes and eventually there is a wall toward the end called Alzheimer’s Disease. This can all sound a bit daunting and may even lead us to feel that we are not up for this constant battle, but the truth is that each and every hurdle we face through the gauntlet of aging is either somewhat or entirely under our control.
In fact there are only two causes of death (unintentional injury #3 and Septicemia #11) in the top 12. But death by unintentional injury (unintentional falls, traffic deaths, and unintentional poisoning deaths) can be greatly reduced by driving more carefully, strengthening our core, and avoiding drinking suspect chemicals. So, Septicemia (the result of a bacterial infection in the bloodstream) is the only one that we have no control over.
By doing all the right things we can overcome the obstacles that life throws at us, destroy the gauntlet, and enjoy every minute of it. Unless we get Septicemia.
Our Biology - Aging at The Cellular Level
We are our cells and our cells are us for what affects us at the cellular level will affect us at the anatomical level. The health and longevity of our body is inextricably tied to the health of our cells. So whatever we do in our quest to expand our healthspan we must always ask ourselves - is this good for my cells?
Our Cells
There are around 37.2 trillion cells within the human body, give or take a few billion, and we can add another 40 trillion non-human cells (bacteria) into the mix. Each of these cells has its own lifespan, its own life for that matter. A cell is created from a tissues stem cell, it performs it required job throughout its life, it divides itself 50 to 70 times during its lifetime, and then it dies. This is all predetermined and orderly.
There are many different kinds of cells, each with its own job to do and each with its own lifespan, ranging from a few weeks to almost two years, and some very special cells will last for the lifetime of its host (i.e. cardiac muscle cells). Generally speaking, as goes the health of our cells goes the health of us.
Cellular Senescence
So, normal cells don’t exactly roll over and die. After a certain number of replications, they go into a non-replicating state known as “replicative senescence” which is triggered by a DNA damage response which results from the shortening of telomeres during each cellular division process. Cells can also be induced to senescence independent of the number of cellular divisions via DNA damage in response to elevated reactive oxygen species (free radicals) and telomere erosion. The number of senescent cells in tissues rises substantially during normal aging. Cellular senescence is not always a state of pre-death for the cell, sometimes it can be just a pause in the cells replication process, giving the cell time to repair DNA damage before replication can continue. It is believed that this halt in the replication process is the cells attempt to avoid becoming cancerous.
Although senescent cells can no longer replicate, they remain metabolically active secreting numerous biologically active factors, including the proinflammatory cytokine interleukin (IL)-6. It has been suggested that the low-level chronic inflammation often observed during aging in tissues without obvious infection is due to senescent cells. And inflammation causes or is a major contributor to virtually every major age-related disease that we know of, including cancer.
The catch-22 of aging: Cells go senescent instead of turning cancerous, but senescent cells, in turn, create inflammation that helps cause other cells to become cancerous.
One more thing - the most powerful and malign pockets of senescent cells are found in one particular kind of human tissue, fat. There is a strong correlation between increased visceral fat, chronic inflammation, and age-related diseases.
Inflammation and Interleukin-6 (IL-6)
IL-6 is a cytokine, a pro-inflammatory protein secreted by various tissues to help fight off infections and heal wounds. But in older people, IL-6 and other inflammatory cytokines seem to be hanging around all the time, in ever-higher levels, for no apparent reason. The older we get, the more inflammation we carry around in our bodies. IL-6 is deadly and it correlates directly with mortality rates. IL-6 is bad.
IL-6 is a myokine, a cytokine that is produced and released by muscle cells (myocytes) in response to muscular contractions. Myokines have multiple functions. Primarily, they are involved in exercise-associated metabolic changes, as well as in the metabolic changes following training adaptation. They also participate in tissue regeneration and repair, maintenance of healthy bodily functioning, immunomodulation; and cell signaling, expression and differentiation. The IL-6 myokines are released prior to, not in reaction to, the inflammatory cytokine response to exercise. So, IL-6 has an anti-inflammatory effect. IL-6 is good.
Exercise generates huge amounts of IL-6, but in that context it actually has beneficial effects, such as signalling the liver to start converting fat to fuel. “In exercise, it’s actually anti-inflammatory.” Hence, exercise gives us all the positive effects of IL-6 without the negative ones.
Telomeres
A telomere is a region of repetitive nucleotide sequences at each end of a chromosome, which protects the end of the chromosome from deterioration or from fusion with neighboring chromosomes. This ending sequence is non-essential and is present to protect the chromosomes DNA during replication. Over time, due to each cell division, the telomere ends become shorter.
Telomere shortening in humans can induce replicative senescence, which blocks cell division. This mechanism appears to prevent genomic instability and development of cancer in human aged cells by limiting the number of cell divisions. However, shortened telomeres impair immune function that might also increase cancer susceptibility.
If telomeres become too short, they have the potential to unfold from their presumed closed structure. The cell may detect this uncapping as DNA damage and then either stop growing, enter cellular old age (senescence), or begin programmed cell self-destruction (apoptosis). Although telomere length appears to be correlational to aging the cause and effect relationship is far from proven, leaving open the idea that maybe it’s aging that affects telomere length, or at least that the rate of telomere shortening can rely on controllable factors.
Calorie Restriction
There is a lot of information floating around that indicates that a diet of restricted caloric intake can extend lifespan in different species, but the science is still out on this since there have been other studies that show no increase in lifespan. But even if we assume that calorie restriction will enhance our longevity, being underweight is the natural consequence of calorie restriction and its side-effects will negatively impact the adventurous lifestyle that we are trying to achieve.
A wealth of good epidemiological data points to the fact that it’s better to be a little overweight (i.e. BMI of 25) than to be seriously underweight (BMI below 21). The reason is that very skinny people may not have the fat reserves they need to survive an infection, particularly as they get older.
Remember, living longer is not the goal, it’s the bonus.
A Billion Heart Beats or The Rate of Living Theory
The rate of living theory states that the faster an organism’s metabolism, the shorter its lifespan, based on the observation that larger animals outlived smaller ones, and that the larger animals had slower metabolisms. Studies have shown that the basal metabolic rate of mammals could accurately be predicted by taking 3/4 the power of body weight (A cat with 100 times the mass of a mouse will consume only 32 times the amount of calories (Kleiber's law). In plants it’s closer to 1 to 1.
This theory is further validated by the Free Radical Theory which states that organisms age over time due to the accumulation of damage from free radicals in the body. It also showed that metabolic processes, specifically in the mitochondria (oxygen synthesized energy production), are prominent producers of free radicals. Plants don’t use mitochondria for energy production.
Studies in humans with 100+ year life spans have shown a link to decreased thyroid activity (lowered metabolic rate) to their longevity. However, the ratio of resting metabolic rate to total daily energy expenditure can vary between 1.6 and 8.0 between species of mammals. Tying this all together - heart rate, breathing rate, and overall metabolism are all interrelated. If we could reduce our resting metabolism rate, maybe we could slow the rate of aging. One of the major adaptations to cardiorespiratory exercise is a lowering of the resting metabolic rate.
Note that these studies prove correlation and not cause and effect, and there are many other factors to be considered for the causes of aging, but this should qualify as one of those possible factors worth considering. Let’s put it in the anti-aging quiver.
Our Cells
There are around 37.2 trillion cells within the human body, give or take a few billion, and we can add another 40 trillion non-human cells (bacteria) into the mix. Each of these cells has its own lifespan, its own life for that matter. A cell is created from a tissues stem cell, it performs it required job throughout its life, it divides itself 50 to 70 times during its lifetime, and then it dies. This is all predetermined and orderly.
There are many different kinds of cells, each with its own job to do and each with its own lifespan, ranging from a few weeks to almost two years, and some very special cells will last for the lifetime of its host (i.e. cardiac muscle cells). Generally speaking, as goes the health of our cells goes the health of us.
Cellular Senescence
So, normal cells don’t exactly roll over and die. After a certain number of replications, they go into a non-replicating state known as “replicative senescence” which is triggered by a DNA damage response which results from the shortening of telomeres during each cellular division process. Cells can also be induced to senescence independent of the number of cellular divisions via DNA damage in response to elevated reactive oxygen species (free radicals) and telomere erosion. The number of senescent cells in tissues rises substantially during normal aging. Cellular senescence is not always a state of pre-death for the cell, sometimes it can be just a pause in the cells replication process, giving the cell time to repair DNA damage before replication can continue. It is believed that this halt in the replication process is the cells attempt to avoid becoming cancerous.
Although senescent cells can no longer replicate, they remain metabolically active secreting numerous biologically active factors, including the proinflammatory cytokine interleukin (IL)-6. It has been suggested that the low-level chronic inflammation often observed during aging in tissues without obvious infection is due to senescent cells. And inflammation causes or is a major contributor to virtually every major age-related disease that we know of, including cancer.
The catch-22 of aging: Cells go senescent instead of turning cancerous, but senescent cells, in turn, create inflammation that helps cause other cells to become cancerous.
One more thing - the most powerful and malign pockets of senescent cells are found in one particular kind of human tissue, fat. There is a strong correlation between increased visceral fat, chronic inflammation, and age-related diseases.
Inflammation and Interleukin-6 (IL-6)
IL-6 is a cytokine, a pro-inflammatory protein secreted by various tissues to help fight off infections and heal wounds. But in older people, IL-6 and other inflammatory cytokines seem to be hanging around all the time, in ever-higher levels, for no apparent reason. The older we get, the more inflammation we carry around in our bodies. IL-6 is deadly and it correlates directly with mortality rates. IL-6 is bad.
IL-6 is a myokine, a cytokine that is produced and released by muscle cells (myocytes) in response to muscular contractions. Myokines have multiple functions. Primarily, they are involved in exercise-associated metabolic changes, as well as in the metabolic changes following training adaptation. They also participate in tissue regeneration and repair, maintenance of healthy bodily functioning, immunomodulation; and cell signaling, expression and differentiation. The IL-6 myokines are released prior to, not in reaction to, the inflammatory cytokine response to exercise. So, IL-6 has an anti-inflammatory effect. IL-6 is good.
Exercise generates huge amounts of IL-6, but in that context it actually has beneficial effects, such as signalling the liver to start converting fat to fuel. “In exercise, it’s actually anti-inflammatory.” Hence, exercise gives us all the positive effects of IL-6 without the negative ones.
Telomeres
A telomere is a region of repetitive nucleotide sequences at each end of a chromosome, which protects the end of the chromosome from deterioration or from fusion with neighboring chromosomes. This ending sequence is non-essential and is present to protect the chromosomes DNA during replication. Over time, due to each cell division, the telomere ends become shorter.
Telomere shortening in humans can induce replicative senescence, which blocks cell division. This mechanism appears to prevent genomic instability and development of cancer in human aged cells by limiting the number of cell divisions. However, shortened telomeres impair immune function that might also increase cancer susceptibility.
If telomeres become too short, they have the potential to unfold from their presumed closed structure. The cell may detect this uncapping as DNA damage and then either stop growing, enter cellular old age (senescence), or begin programmed cell self-destruction (apoptosis). Although telomere length appears to be correlational to aging the cause and effect relationship is far from proven, leaving open the idea that maybe it’s aging that affects telomere length, or at least that the rate of telomere shortening can rely on controllable factors.
Calorie Restriction
There is a lot of information floating around that indicates that a diet of restricted caloric intake can extend lifespan in different species, but the science is still out on this since there have been other studies that show no increase in lifespan. But even if we assume that calorie restriction will enhance our longevity, being underweight is the natural consequence of calorie restriction and its side-effects will negatively impact the adventurous lifestyle that we are trying to achieve.
A wealth of good epidemiological data points to the fact that it’s better to be a little overweight (i.e. BMI of 25) than to be seriously underweight (BMI below 21). The reason is that very skinny people may not have the fat reserves they need to survive an infection, particularly as they get older.
Remember, living longer is not the goal, it’s the bonus.
A Billion Heart Beats or The Rate of Living Theory
The rate of living theory states that the faster an organism’s metabolism, the shorter its lifespan, based on the observation that larger animals outlived smaller ones, and that the larger animals had slower metabolisms. Studies have shown that the basal metabolic rate of mammals could accurately be predicted by taking 3/4 the power of body weight (A cat with 100 times the mass of a mouse will consume only 32 times the amount of calories (Kleiber's law). In plants it’s closer to 1 to 1.
This theory is further validated by the Free Radical Theory which states that organisms age over time due to the accumulation of damage from free radicals in the body. It also showed that metabolic processes, specifically in the mitochondria (oxygen synthesized energy production), are prominent producers of free radicals. Plants don’t use mitochondria for energy production.
Studies in humans with 100+ year life spans have shown a link to decreased thyroid activity (lowered metabolic rate) to their longevity. However, the ratio of resting metabolic rate to total daily energy expenditure can vary between 1.6 and 8.0 between species of mammals. Tying this all together - heart rate, breathing rate, and overall metabolism are all interrelated. If we could reduce our resting metabolism rate, maybe we could slow the rate of aging. One of the major adaptations to cardiorespiratory exercise is a lowering of the resting metabolic rate.
Note that these studies prove correlation and not cause and effect, and there are many other factors to be considered for the causes of aging, but this should qualify as one of those possible factors worth considering. Let’s put it in the anti-aging quiver.
Our Chemistry - Aging at The Molecular
There is a circular interconnectivity between our anatomy (our major body systems), our biology (our native and non-native cells within us), and our chemistry (the molecules within us and around us) that all determine how we age. It is the interaction of these things that determines how we age. As we dig deeper down microscopically, for lack of a better description, we relinquish more and more control over these interactions.
Our anatomy (which have the most control over) uses our biology as the tools to carry out its functions, and our biology uses our chemistry as its materials. When we run, we tell our anatomy to perform a series of functions to carry out this task. Our anatomy (our legs, lungs, and heart) uses our biology (our red blood cells) to carry out the exchange of O2 and CO2 with our working muscle cells and the environment. Our chemistry (O2, CO2, proteins, carbohydrates, fats, and the various required hormones) are the building blocks whose availability allow us to perform this task.
So while we have no control over the tools we are forced to use, we do have some (maybe a lot of) control over how we use them and the materials that are available for them to use.
Sirtuins and Resveratrol
Sirtuins are a class of proteins that exist across many species from yeast to worms to mice, monkeys, and even humans, and have been shown to influence a wide range of cellular processes like aging, inflammation and stress resistance, as well as energy efficiency and alertness during low-calorie situations. Basically, when environmental resources become scarce, sirtuin activity increases due to a link to the cells energy status, and shifts cellular activity from growth mode to repair mode.
By inhibiting the growth of the cell, in essence, it is putting a hold on the cell’s aging, subsequently slowing the organisms aging. This validates the disposable soma theory which states that it makes no sense for the organism to grow and reproduce during times of famine, so it might as well go into repair mode until times get better.
Interestingly, lab studies on resveratrol, a type of natural phenol produced by several plants in response to injury or, when the plant is under attack by pathogens such as bacteria or fungi show it to have an effect similar to sirtuins on cellular activity. Sources of resveratrol in food include the skin of grapes, blueberries, raspberries, mulberries, and peanuts.
mTOR and Rapamycin
The mammalian target of rapamycin (mTOR) is a kinase (an enzyme critical to cellular metabolism) that controls protein and lipid synthesis, cell size, proliferation, differentiation, autophagy and metabolism and is stimulated through multiple inputs such as growth factors, amino acids, cellular energy status, stress and oxygen.
mTOR activation is required for muscle protein synthesis and skeletal muscle hypertrophy in humans in response to both physical exercise and ingestion of certain amino acids. mTOR activation is determined by the nutrient levels of the organism and its deactivation during times of nutritional stress allows conservation of resources and a “cleaning up” of unproductive cells and cell organelles. Hence, a reduction in caloric intake inhibits mTOR and extends lifespan.
When nutrients are restricted (ie. drought or famine) the body responds by transferring energy from cell growth to cell repair and when nutrients are plentiful, the body puts that energy back into growth and reproduction.
There is a catch-22 in the battle against aging that applies here - what’s good for cell growth (eg. staying younger) is also good for cancer cell growth, and what’s good for longevity also promotes frailty.
How do we get the benefits of decreased mTOR through calorie restriction and fasting, while also getting the strength and growth benefits of elevated mTOR levels? We want just enough mTOR to build new muscle, but then we want the levels to drop so that we get the benefits of cell repair.
Read - mTOR, Finding The Balance (coming soon)
Free Radicals and Antioxidants
Free radicals reactive oxygen species (ROS) are generated by our body by various endogenous systems, exposure to different physiochemical conditions, or pathological states. A balance between free radicals and antioxidants is necessary for proper physiological function. If free radicals overwhelm the body's ability to regulate them, a condition known as oxidative stress ensues. Free radicals thus adversely alter lipids, proteins, and DNA and trigger a number of human diseases.
Initial studies showed that by increasing the amount of antioxidants in our system (through supplementation) we could reduce the amount of free radicals and the damage that they cause. Upon further examination, it was realized that these studies only improved the average lifespan in the subjects (monkeys) and had no effect on the maximum lifespan. In fact, a massive JAMA review of 68 clinical trials of antioxidants found that in a majority of the studies, people who took vitamin A, vitamin E, and beta-carotene actually seemed to increase their risk of death.
Our bodies have a natural production of antioxidants and powerful enzymes that soak up the excess free radicals that we experience from nature and that are produced during exercise. Supplementation of antioxidants seems to deactivate our own antioxidant production. Some speculate that free-radicals are actually beneficial in that they trigger a beneficial stress response that our entire system benefits from.
Read - Antioxidants and Free Radicals (coming soon)
Our anatomy (which have the most control over) uses our biology as the tools to carry out its functions, and our biology uses our chemistry as its materials. When we run, we tell our anatomy to perform a series of functions to carry out this task. Our anatomy (our legs, lungs, and heart) uses our biology (our red blood cells) to carry out the exchange of O2 and CO2 with our working muscle cells and the environment. Our chemistry (O2, CO2, proteins, carbohydrates, fats, and the various required hormones) are the building blocks whose availability allow us to perform this task.
So while we have no control over the tools we are forced to use, we do have some (maybe a lot of) control over how we use them and the materials that are available for them to use.
Sirtuins and Resveratrol
Sirtuins are a class of proteins that exist across many species from yeast to worms to mice, monkeys, and even humans, and have been shown to influence a wide range of cellular processes like aging, inflammation and stress resistance, as well as energy efficiency and alertness during low-calorie situations. Basically, when environmental resources become scarce, sirtuin activity increases due to a link to the cells energy status, and shifts cellular activity from growth mode to repair mode.
By inhibiting the growth of the cell, in essence, it is putting a hold on the cell’s aging, subsequently slowing the organisms aging. This validates the disposable soma theory which states that it makes no sense for the organism to grow and reproduce during times of famine, so it might as well go into repair mode until times get better.
Interestingly, lab studies on resveratrol, a type of natural phenol produced by several plants in response to injury or, when the plant is under attack by pathogens such as bacteria or fungi show it to have an effect similar to sirtuins on cellular activity. Sources of resveratrol in food include the skin of grapes, blueberries, raspberries, mulberries, and peanuts.
mTOR and Rapamycin
The mammalian target of rapamycin (mTOR) is a kinase (an enzyme critical to cellular metabolism) that controls protein and lipid synthesis, cell size, proliferation, differentiation, autophagy and metabolism and is stimulated through multiple inputs such as growth factors, amino acids, cellular energy status, stress and oxygen.
mTOR activation is required for muscle protein synthesis and skeletal muscle hypertrophy in humans in response to both physical exercise and ingestion of certain amino acids. mTOR activation is determined by the nutrient levels of the organism and its deactivation during times of nutritional stress allows conservation of resources and a “cleaning up” of unproductive cells and cell organelles. Hence, a reduction in caloric intake inhibits mTOR and extends lifespan.
When nutrients are restricted (ie. drought or famine) the body responds by transferring energy from cell growth to cell repair and when nutrients are plentiful, the body puts that energy back into growth and reproduction.
There is a catch-22 in the battle against aging that applies here - what’s good for cell growth (eg. staying younger) is also good for cancer cell growth, and what’s good for longevity also promotes frailty.
How do we get the benefits of decreased mTOR through calorie restriction and fasting, while also getting the strength and growth benefits of elevated mTOR levels? We want just enough mTOR to build new muscle, but then we want the levels to drop so that we get the benefits of cell repair.
Read - mTOR, Finding The Balance (coming soon)
Free Radicals and Antioxidants
Free radicals reactive oxygen species (ROS) are generated by our body by various endogenous systems, exposure to different physiochemical conditions, or pathological states. A balance between free radicals and antioxidants is necessary for proper physiological function. If free radicals overwhelm the body's ability to regulate them, a condition known as oxidative stress ensues. Free radicals thus adversely alter lipids, proteins, and DNA and trigger a number of human diseases.
Initial studies showed that by increasing the amount of antioxidants in our system (through supplementation) we could reduce the amount of free radicals and the damage that they cause. Upon further examination, it was realized that these studies only improved the average lifespan in the subjects (monkeys) and had no effect on the maximum lifespan. In fact, a massive JAMA review of 68 clinical trials of antioxidants found that in a majority of the studies, people who took vitamin A, vitamin E, and beta-carotene actually seemed to increase their risk of death.
Our bodies have a natural production of antioxidants and powerful enzymes that soak up the excess free radicals that we experience from nature and that are produced during exercise. Supplementation of antioxidants seems to deactivate our own antioxidant production. Some speculate that free-radicals are actually beneficial in that they trigger a beneficial stress response that our entire system benefits from.
Read - Antioxidants and Free Radicals (coming soon)
Exercise and Longevity
It is well understood that exercise can partially reverse the effects of the aging process on physiological functions, preserve functional reserve in the elderly, and slow down aging in those not so elderly. Numerous studies have shown that just maintaining a minimum quantity and quality of exercise decreases the risk of death, prevents the development of certain cancers, lowers the risk of osteoporosis and increases longevity.
That would be great if our goal was to merely slow down the process and gain a few years on the back end, but that is not our goal. Our goal is to crush the aging process, live a life of adventure and intensity, sliding across the finish line beaten, battered, and bloodied with no regrets to look back on, and if we add a few years in the process, then all the better. It is going to take a little more effort than a walk around the block and a few push ups, but then, great things don't come easy do they.
If we have the power to take control of the aging process, then exercise and nutrition are the tools we must use to do this. By getting stronger, fitter, and healthier, we will not only reduce the amount of physical decline as we push deeper into our later years, but actually improve on our physicality.
See - Our Potential Peak Performance (coming soon)
That would be great if our goal was to merely slow down the process and gain a few years on the back end, but that is not our goal. Our goal is to crush the aging process, live a life of adventure and intensity, sliding across the finish line beaten, battered, and bloodied with no regrets to look back on, and if we add a few years in the process, then all the better. It is going to take a little more effort than a walk around the block and a few push ups, but then, great things don't come easy do they.
If we have the power to take control of the aging process, then exercise and nutrition are the tools we must use to do this. By getting stronger, fitter, and healthier, we will not only reduce the amount of physical decline as we push deeper into our later years, but actually improve on our physicality.
See - Our Potential Peak Performance (coming soon)
“Exercise is an incredibly effective mechanism to drive protein turnover, kind of flushing out the old proteins.”
What Can We Do About Aging?
Someday we will all die (most likely) and trying to deny the inevitability of death would be an incredible waste of time and energy, and would distract/detract us from living the adventurous life that we so desire. So, the goal is not to find the proverbial fountain of youth and live forever, but to minimize the effects of aging, flatten the downward trajectory, and extend our healthy and fit years, and squeeze in as many more years of adventure as we possibly can. And when the end comes, it won’t arrive in the form of years of invalidity, living in a nursing home or a hospital connected to all kinds of tubes and wires. If we are lucky, it will come swiftly, and if we are really lucky, it will arrive as we are doing one of the things we love doing the most.
There are no guarantees in life. We may do all right things and still get cancer, some infectious disease, or maybe we just step off the curb at the wrong time. But there are quite a few things that we can do that will skew the odds of a longer, more vibrant future in our favor, or at least give us a more adventurous present.
Getting Our Heads Into It
Start by taking the oath - “I will never utter the words - I’m too old to do that.” Let's promise ourselves that our body will determine when we're too old to do something, not our minds.
There are no guarantees in life. We may do all right things and still get cancer, some infectious disease, or maybe we just step off the curb at the wrong time. But there are quite a few things that we can do that will skew the odds of a longer, more vibrant future in our favor, or at least give us a more adventurous present.
Getting Our Heads Into It
Start by taking the oath - “I will never utter the words - I’m too old to do that.” Let's promise ourselves that our body will determine when we're too old to do something, not our minds.
“When we say we’re getting too old to do something, that’s when we are.”
Claiming we are too old to do something is the worst excuse that we can possibly concoct because it is the best, and odds are that whoever you tell it to will agree with you wholeheartedly. It is not only the most “legitimate” excuse, it is a self-fulfilling prophecy, and it’s likely to get you plenty of empathy, sympathy, and lots of company at the retirement home.
By predetermining that we are too old to do something, not only are we already choosing that more direct route to old age, but we are denying the possibility that we aren’t too old to do it.
Exercise
Get exercising to increase your cardio capacity and strengthen your heart. Just adding a daily walk will add several years to your life. But don’t stop there, because just walking gets boring. Kick it up a notch and start hiking, or biking, or mountain biking! When you’re hiking, add a pack, and put some weight in it. Make it more challenging than it has to be, this is when you will start to benefit from it.
Get stronger by lifting weights and train with intensity to increase bone density and muscle mass. The benefits of training under intense conditions are readily obvious soon after you get started, but the underlying benefits are even more important. Putting our bodies under stress (short-term stress) unleashes a cascade, no an avalanche, of hormones whose job it is to repair and rejuvenate the affected tissues, but maybe the most important benefit is the effect these chemicals have on the rest of the body during the process.
Nutrition
Eat more fiber. Much more. As much of it as possible. You know it’s healthy, but it may be the single easiest thing you can do to improve your long-term health. Or at least you will be very regular!
Besides fiber, without going into too much detail here, you need to try to consume the same or similar foods that our ancestors did on the Savanna a thousand generations ago. Back then we were hunter gatherers so it would be best to eat the things that they hunted and gathered. Meats, healthy fats, nuts, fruits, and greens - by focusing on these items we can be assured that we are getting the nutrients that our bodies evolved to need over millions of years.
Note: There is some controversy over the ingestion of grains. Grains only became a part of the human diet very late in our evolution (about 10 to 15 thousand years ago) and it can be argued that their health benefits can be suspect at best. But there are numerous studies showing the beneficial effects that fiber has on our intestinal health as well as our overall longevity and whole grains are a fantastic source.
Play
Ultimately, we need to play. Play like we did when we were children. We need to run, jump, climb, ride, explore, fall down, get banged up, scraped up, cut up, and maybe even break something once in awhile. We need to experience the pain and discomfort that comes with the adventure, so we can be reminded that we are alive, not numb and complacent on the couch. We need to bring back that inner child that we put away way too prematurely and so long ago.
Playing incorporates all of the things we need to do physically and mentally to delay and diminish the downward aging cycle.
Conclusion
While emulating the living habits of our caveman ancestors provides a solution to get us into our later years, it is not a foolproof way to get through them. The fact of the matter is that our ancestors did not live that deep into old age so unfortunately the roadmap that they provide can only get us so far. It can be deduced that the bodies that we inherited did not evolve to live any longer than that of our ancestors, so to do so, we will have to develop our own strategies and solutions.
“The idea of death, the fear of it, haunts the human animal like nothing else; it is a mainspring of human activity - activity largely designed to avoid the fatality of death, to overcome it by denying in some way that it is the final destiny for man” - Ernest Becker
On a personal note - I have never and will never utter the words - "I am too old for this", ever! I know the day will come when my body is just not capable of performing a requested task, but I hope it is my body telling me this and not my mind. The day you say, "I am too old for this" is the day you are, and you have just taken the first of many steps down the path to old age. Don't take that first step!
"The mind quits before the body."
A few final thoughts: We are being naturally pulled in the direction of old age from the inside as well as from the outside. This creates the challenge! Our fight against aging may be as much trickery as it is brute force. There is no single thing we can do to increase our longevity. Our strategy must involve a variety of things, of which there are many. Thankfully, most of these overlap each other.
We don’t have to accept the fate of the downward spiral of aging and its effects. We are not helpless in this endeavor, not by a long shot. But it starts with developing the conviction, the mind-set, and a plan. But, most-importantly, we just need to get started. And that start can be as simple as just getting moving. Just get up and go!