Healthy aging specialists, like I, are dedicated to the science of healthy aging. We emphasize the enhancement of health over the treatment of illness; focusing on disease prevention, wellness, and quality of life by using randomized double-blind placebo controlled peer reviewed studies whenever possible. This approach is based on the fact that today the majority of men and women already possess a genetic makeup that will allow us to live well into our 100s.

The key is to make the best of the genes we have so that we can live better and longer. By incorporating these practices into our daily lives we can reverse aging and illness and compress the time we are sick. As I like to tell my patients, we can’t stop the aging process, but we can definitely manage it and slow it down.

As a physician, I know that the second half of your life can—and should—be the best part of your life. I’m confident in saying that even though every day, we are aging—everything ages! But the truth is, we don’t have to get old as we age. We can get better as we age.

To me, getting “old” means the deterioration of health accompanied by declining energy levels, loss of sexual function, and loss of zest for life. I don’t want any part of that for myself, my patients,  or my readers and I bet you don’t either.

It has now been twenty years since I began my complete physical transformation. What’s so exciting to me is that what I accomplished in just a few months has lasted. Today, not only do I feel great, I’ve been able to maintain my physique and my good health over all these years. In fact, in many ways, I’m stronger, healthier, and more fit than I was when I first got into shape way back in 1998.

I’ve been able to stay strong and lean, reduce my cholesterol levels, reduce internal or “silent” inflammation, reduce blood sugar levels, eliminate biomarkers for heart attack and stroke, and avoid diabetes. I have actually stopped the progression of my heart disease that had started when I was in my twenties. I have the mental focus, clarity, and sharpness necessary to keep myself more productive and creative than ever.

At 80 I’m working every day, building my medical practice, writing best-selling books and blogs, training consistently, helping my grandkids, and learning more about exercise, nutrition, and preventive medicine. I love my life!

But back in 1997, my future did not look so bright. When I discovered that my own hormone levels were deficient, traditional medicine said (and still does) that andropause, or declining testosterone, is not a disease but a fact of life, so it shouldn’t be treated.

When I was losing muscle tissue and strength to sarcopenia (age-related muscle and strength loss) 20 years ago, conventional doctors once again told me to just accept that I was getting older, and basically, just suck it up and get over it. But even 20 years ago, I knew that they were wrong and scientific studies over the past 10 years have confirmed it. The sad part is, most men continue to hear this same message from their doctors even today.

What most docs still don’t get is that aging is not the enemy, and it’s not a disease. In fact, by its very definition, aging is a gradual change in your body that doesn’t result from disease. Disease is the deviation or interruption of the normal function of any part or system of our bodies; so, I think it is the duty of all responsible physicians to treat the disease of andropause.

Each of us has a unique set of inherited predispositions for certain health issues: That’s your DNA code. On top of that, your lifestyle choices contribute to whether these tendencies will materialize.

Lifestyle can definitely trump genetics. So instead of accepting disease or waiting for it to appear, you can learn how to use my health strategies to keep your body metabolically and physiologically in balance. That’s the Life Plan.

I do not accept as fact traditional medicine’s proclamation that there’s nothing we can do about “natural declines” that occur as we get older, when in fact there’s everything we can do about them. When I was on The Doctors Show in 2012, the producers cleverly built the segment not only around my book but around my name. I think the acronym they created really sums up my philosophy (and I wish I’d thought of it myself). My book teaches you how to master these four core areas as we age:

■ L—Levels of hormones: Reversing hormone deficiencies keeps you energized, vibrant, healthy, and slows and actually reverses the aging process. Declining hormone levels are the result of a disease process, not aging, and should be treated. In my opinion, it’s malpractice for doctors to ignore declining hormone levels and write them off as an acceptable part of aging.

Study after study has shown that increasing testosterone and other critical hormone levels in deficient adults greatly affects health in many positive ways, from improving bone mineral density, sexual function, libido, and body composition to reducing the risk for heart disease, diabetes, cancer, stroke, and Alzheimer’s disease.

An optimal level of testosterone can actually decrease or eliminate Metabolic Syndrome, obesity, diabetes, and high blood pressure and cholesterol. And testosterone is not the only hormone you need to be concerned with: Later in my book, you’ll learn about all of the hormones that you need to be tested for, and how to enhance existing levels if you’re deficient.

■ I—Insulin control: Maintaining low insulin levels keeps you from getting fat and cascading into poor health, so it’s critical to learn how to manage it through diet. Recent numerous scientific studies have confirmed that high levels of insulin cause the other components of Metabolic Syndrome to develop—obesity, high triglycerides, elevated blood pressures, inflammation, and glucose intolerance.

Excess levels of insulin are also thought to be the single most important factor that accelerates the aging process. High insulin levels affect your percent body fat, blood lipid levels, glucose tolerance, aerobic capacity, muscle mass, strength, and immune function. High insulin levels prevent you from burning your own body fat for energy and make you totally dependent on carbohydrates for your energy source.

However, when you structure a nutrition program around keeping blood sugars and insulin levels in check as I have, you will get a huge benefit beyond improved health—increased muscle size.

In just four to seven days of eating “clean” you can move your blood sugar and insulin levels toward their ideal range, and by two weeks you will no longer be plagued by feelings of hunger, deprivation, and cravings. You’ll experience a marked improvement in your mental focus, exercise endurance, strength, optimal health, muscularity, and leanness. These are the reasons why my diet plans are all structured to lower insulin levels.

■ F—Food as fuel: The foods we eat can change our lives by providing constant energy and promoting good health. Your current diet may be filled with processed foods, unhealthy proteins, and sugar-laden simple carbohydrates that all taste great but really accelerate aging and disease.

All these bad foods are quickly stored as body fat and arterial plaque. They also suck the energy right out of you, add weight, and create the perfect conditions for stroke, diabetes, heart disease, cancer, and Alzheimer’s disease.

Always remember, what you put into your mouth can either hurt you or help you. I’ll teach you how to change the way you eat so that you can begin to lose weight and reverse your potential for illness.

■ E—Exercise: A comprehensive exercise program can not only transform our bodies but will improve our thinking and even our sex lives. And it only takes one hour of working out a day (4.2% of your day). One goal of the Life Plan is preserving bone density and enhancing muscle growth. Without it, the average American male can expect to gain approximately one pound of body fat every year between ages 30 and 60 and lose about a half pound of muscle mass each year over the same period. At age 60 and onward it gets even worse as the rise in body fat replaces muscle mass. The largest loss of muscle mass occurs between ages 50 and 75, averaging 25 to 30 percent.

There you have it….L..I..F..E….the 4 keys to staying young and vital as you age!