Fight to vanquish aging
Did you know you have a clock inside of you, and at this very moment, it’s ticking? Our body clock is apparently set to bring about your demise, be it from cardio-vascular disease or cancer, or any of the other chronic diseases thought to be a natural part of aging. Some scientists now believe it is possible to stop or even rewind the body’s internal chronometer. This means all the typical diseases once considered an inescapable part of aging, may arrive later or not at all.
Studies of centenarians, people who live to 100, suggest the feat is achievable. Most of these individuals live that long because they have somehow avoided most of the diseases that burden other folks in their 70s and 80s. How does someone, living in modern-day America, promote true longevity for themselves? The very common diseases of age, especially cardio-vascular disease and diabetes, are more common than ever, despite a concerted effort on the part of Western medicine to reduce cholesterol and lower blood pressure.
It has been reported in these very pages that aging mitochondria lead to a loss of cellular and organismal health. Mitochondria are the structures inside our cells that produce ATP, the form of energy used by our cells. One well-recognized phenomenon in the biological sciences is a progressive decline in mitochondrial function with age, although the causes of this phenomenon are debated.
Hormone shots, anti-wrinkle potions, herbal “miracles,” clearly the business of anti-aging is booming. But virtually all the products touted as age defying are unproven by rigorous science. The benefits claimed are spectacular, and often outrageous. Too often, their sales reveal that these exaggerated claims are not questioned, but purchased in the off chance that the claims hold some sliver of truth. Our society is obsessed with a person’s appearance, yet this is not a good definition of longevity. Is it simply a long lifespan, or is it a long, healthy life with freedom from chronic diseases?
Researchers from a variety of fields have been working toward a molecular fountain of youth. Recent studies have looked at a special class of proteins in our bodies called sirtuins. These have been implicated in a wide range of processes. Sirtuins appear to play an important role in inflammation and stress resistance, as well as energy efficiency and alertness during low-calorie situations. Sirtuins also help to control circadian clocks and mitochondrial function.
A normal part of human aging involves senescence, which is a general wearing out of the body over time. Muscles begin to lose tone and become more easily inflamed. They can also develop insulin resistance. Senescence occurs to the cells of our body as well. Without being able to use insulin, cells aren’t able to take up the glucose needed for activity. This is at least part of the reason many elderly people have trouble getting around, and athletes aren’t able to sustain certain levels of activity as they age.
Another critical function of sirtuins is cell senescence. In cellular physiology, the term is used to describe the process whereby a cell doesn’t die when it has aged sufficiently, but instead, it leaks toxic chemicals into its surroundings. The most dangerous place is into vital organs such as our heart, liver, kidneys and brain. Scientists have long suspected that senescent cells cause us to age, but getting rid of them without harming normal, healthy cells has been challenging.
The health of our genes, and specifically our DNA, is another area of particular study in anti-aging medicine. We know well that our DNA is damaged by time, the environment, and the foods we consume. How and why is our body’s ability to fix DNA dwindling over time? Many researchers point to a previously unknown role for the signaling molecule NAD as a key regulator of protein-to-protein interactions, which is a critical function in DNA repair. NAD is known for its role as a controller of cell-damaging oxidation (think of rust, another example of oxidation). Experiments conducted with mice show that treatment with an NAD precursor lessens age-related DNA damage and that from radiation exposure.
Yet, perhaps the means to achieve this kind of healthy aging is already within reach. Only one intervention has been scientifically documented to extend life. In the medical world, it’s called calorie restriction. For the rest of us, it’s called cutting out excess sugar and carbs. Research has repeatedly demonstrated limiting sugar in your diet is a well-known key to longevity. Can it be so simple? Can something as “easy” as reducing your intake of carbohydrates lead to a long, healthy lifespan?
This is important news even for everyone, even those without diabetes, since blood glucose levels tend to rise as we grow older. Over the last several decades, in animal studies, scientists have found decreasing the number of calories eaten by 30% increases life span by about 30%, as compared to an ordinary diet. And much of that extra life is a healthier life. The animals are more resistant to cancers, and their hearts are in better shape. Whether through physical exercise, diet or drugs, studies also reveal improving glucose metabolism can help to reduce the loss of cognitive abilities, which is the conscious intellectual activity, such as thinking, reasoning, or learning, we all know declines with age.
A doctor who specializes in anti-aging and regenerative medicine (this is a true specialty) interviewed for this article declared, quite emphatically, a longer lifespan is within reach of most people, simply by instituting diet modification and restriction. According to this fellow, our standards as to what constitutes high blood sugar is incorrect. Most physicians are ambivalent when presented with a patient who has a blood sugar reading of 100. Many scientists in the field of anti-aging medicine believe this attitude is dangerous, and needs to be managed more aggressively. Many physicians and scientists believe a blood sugar below 87 will dramatically lower the incidence of the major chronic diseases. And all without a pill, simply by instituting specific and regimented plans for diet and exercise.
Limiting calorie intake (without causing malnutrition) may benefit humans, but studies have not yet proven this sufficiently. Very few people can or want to maintain such low-calorie diets for the decades needed to prove definitively that this approach works. Some recent human studies have suggested this is the case, and calorie restriction does indeed promote health and longevity, but the results have not yet percolated down into mainstream medicine.
Most older Americans live out their final years with at least one or two chronic ailments. The longer their body clock ticks, the more of these disabling conditions they face. Doctors (and drug companies) traditionally treat each of these diseases as it arises. But it would seem a bold new approach is possible. Is it possible to stop or even rewind the body’s chronometer? Research into healthy longevity is progressing, and some exciting new developments have occurred. Many doctors specializing in anti-aging medicine believe we will soon be able to do this, but perhaps we already have the tools to achieve a longer lifespan. The mantra of the age, and certainly these pages, is to live longer and healthier by exercising regularly, and eating better, smarter, and less. To summarize, I have for you two simple words: diet and exercise!
Editor’s note: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at firstname.lastname@example.org.