By Sheri Colberg, PhD
Different tissues and organs change over time at varying rates, so enhancing their function will likely slow your rate of biological aging and, in some cases, even reverse it. Certain biomarkers of biological aging can let you know whether you’re doing better or worse than your actual chronological age would indicate. Some of the more common biomarkers for aging that you can have tested and that you may be able to control follow. Most of them you can’t test on your own, but you will at least know which tests to consider having at some point.
Biomarker #1: Blood Pressure
An easily measured aging biomarker is your systolic blood pressure (recorded as the first number, such as "130" for a reading of "130 over 85"). A normal blood pressure never has a systolic value over about 120, but elevations in it are more common the older you get. Systolic pressures reflect the elasticity of your arteries, or how well they expand when your heart pumps blood into them, and the longer your value stays in a normal (or near normal) range, the younger your vessels are acting. Either have your pressure measured at your next doctor’s visit or step into the nearest pharmacy and measure it yourself for free. Although drugstore testing is less accurate, it will still give you a ballpark idea of your systolic reading. Some things that can help lower it are exercising regularly, losing some weight (especially abdominal), cutting back on salt intake, eating more fish, and taking medications to control it.
Biomarker #2: Blood Glucose and Cholesterol Levels
You can get your fasting blood glucose and cholesterol levels measured at the next visit to your doctor’s office. A normal blood glucose reading after fasting overnight (or going at least eight hours without eating) is between 70 mg/dl and 100; if yours is between 100 and 125, you technically have prediabetes, and over 125 is a diagnosis of diabetes. Any elevation in your glucose levels above normal tends to make your blood vessels age more rapidly for a number of reasons, so staying in a normal range makes them biologically younger. As for your cholesterol, lower total values generally give you a better chance of avoiding coronary or other vessel disease, but to really know your risk, find out the subfractions of the different types of cholesterol because some are beneficial, while others are more harmful. For example, not all "LDL-cholesterol" is bad; the large, fluffy variety is actually harmless.
Biomarker #3: Aerobic Capacity and Muscle Strength
You can get an exercise stress test done that measures your maximal aerobic capacity (known as maximum oxygen consumption testing). This test may be one of the best ways to measure your biological age as it examines the integrated function of your heart, lungs, blood vessels, and muscles all in one test. Such testing is usually done either by cardiologists to diagnose heart problems or by exercise physiologists to find out how fit and young your cardiovascular system is. In general, the higher your maximal aerobic capacity, the younger you are staying. Fortunately, you can improve your aerobic capacity on your own with an exercise training program.
Along the same vein, you can also get an exercise professional to measure your hand grip strength with a special dynamometer. Declining strength on this test is indicative of a loss of muscle mass throughout your body and a higher biological age. The good news is that an overall resistance training program can improve your grip strength, along with the strength of other muscles throughout your body, thus slowing or preventing biological aging associated with loss of muscle.
Biomarker #4: Bone Mineral Density
Changes in bone mineral density with aging, together with arthritis and osteophytes (bone spurs), have additionally been a good biomarker that can be determined from a simple hand x-ray or a DXA bone mineral density scan. If your bone minerals are lower than expected for your age, you can positively affect them through dietary changes (such as more calcium), exercise training (especially weight-bearing and resistance workouts), and hormone therapies including estrogen replacement and vitamin D.
Some of the remaining markers are either trickier to interpret or harder to measure. For example, to test your skin’s elasticity, pinch up the skin on the back of one hand between your thumb and forefinger of your other hand. Let go and watch how quickly your skin returns to its normal shape. Compare your skin’s response to that of your kids or grandkids, and you’ll likely be able to see that they’re biologically younger (meaning that their skin snaps back into place faster than yours). Of course, this measure is completely subjective and can be greatly affected by everyday things, such as how well hydrated you are. Dehydrated skin stays pinched longer than when it’s fully hydrated, regardless of your age.
Biomarker #6: Mental Function
How well you function mentally (your "cognitive performance") can be measured with various tests, including ones to detect mild cognitive changes and dementia, but almost all of them must be administered to you by a mental health or other professional. The state of your mind is often reflective of similar changes in the rest of your body; accordingly, exercising your body generally also improves the healthiness of your mental processes. In lieu of searching out whether you’re demented yet, we suggest that you better use your time by doing mental exercises (such as trying to remember things, doing crossword puzzles, or learning a new language) that can improve your mental functioning and your memory, as well as keep your mind sharp for longer. Be regularly physically active will also help improve your mental function naturally.
Biomarker #7: Systemic Inflammation
You can ask your doctor to test your blood for various markers of systemic inflammation. When certain compounds in blood are present, your blood vessels may function less effectively. Over time, such changes can result in permanent injury, plaque formation in arteries, and heart attacks or strokes. Scientists are learning more every day about what the various markers do or indicate, but at this point, it’s still an inexact science, not one that is worth spending your money on testing since interpreting what various levels of them mean would be guesswork at best.
Biomarker #8: Reaction Time
Your reaction time, which is a measure of how quickly you respond to stimuli, can be measured with special testing equipment, but your doctor is unlikely to have it in his or her office. Generally speaking, though, your ability to react quickly reflects how well your nerves conduct their messages, and the faster they go, the younger you likely are, biologically speaking.
In any case, it’s never too late to get started on feeling and looking younger, and you’re sure to reap some of its benefits as soon as you begin. Most of the healthy lifestyle changes and medical interventions that you can implement to vastly increase your likelihood of staying and feeling young for longer are not nearly as radical as you may think. For instance, implementing some dietary changes will already begin to lower your risk of certain types of cancer and heart disease and raise your mind’s sharpness. Adding just a little activity to your daily routine can have major benefits, and experts suggest that even 15 to 30 minutes of walking each day is probably enough to gain substantial health benefits. In fact, the risk of prostate cancer in men is vastly lower in anyone who exercises regularly and has regular medical exams.
Sign up for the Diabetes "Fit Brain, Fit Body!" fitness/lifestyle programs or for 5 free Healthy Living Reports at www.lifelongexercise.com, and access more articles and information at www.shericolberg.com. If you need tips for getting safely started on an exercise program, check out The 7 Step Diabetes Fitness Plan. For people with any type of diabetes who are already more active, consult the Diabetic Athlete’s Handbook.
Copyright © 2011 Diabetes In Control, Inc.