Growing old is not for cissies, or so the adage goes, but we’re doing a better job at it now than at any time in history.

The average life expectancy for a man 100 years ago was not much more than 50. It is now nearly 80.

Can we expect adding another 30 years a century from now? Who knows?

Much of our longevity is based on genetics, and since the human genome has been sequenced, we are making great strides in understanding how genetics affects disease. Specific therapies are being designed to treat specific genetic defects. Diseases we thought uniformly fatal a decade ago are now being successfully treated. But many diseases are the result of just plain bad habits. Smoking, obesity, substance abuse — all self-imposed.

A good diet and regular exercise go a long way to helping us age well. I am often asked by my patients about what else they can do to stay healthy into their sixties and seventies. Here are a few common issues for men over 50, and some facts and tips that will help you age well.

First and foremost, get regular check-ups with your primary-care doctor. Many men ignore their health. Early detection of high blood pressure, heart disease and many forms of cancer can be detected and treated early.

Prostate cancer is one of these. Although there is some controversy about screening for this very common disease of older men, one thing is certain: early detection can save lives.

A simple blood test called PSA, which stands for prostate specific antigen, although not perfect is recommended for all men beginning at age 50 — and done yearly until age 70.

Men with a family history of prostate cancer — father, grandfather, uncle or brother — and men of African heritage should begin screening at age 40. A high PSA, greater than 4.0, should signal the need to see a urologist.

In 2016, the majority of afflicted men have prostate cancer diagnosed simply because they had this simple blood test.

It may not detect every patient who has prostate cancer, and many men with high PSAs do not have the disease, since simple prostate enlargement can cause the PSA to rise. But the only way to know is to get the test, so have a discussion with your doctor.

Another common problem for older men is what I call the “hand on the door-handle question”. Just as he is about to exit the examination room, the patient says, “Oh, by the way, doc, is there anything I can do to improve my sex life?” The answer: absolutely. There’s a lot you can do.

First, it is important to know that as we age, we should not expect our performance to be what it was as a 20-year-old. That said, there is no reason a man in his eighties cannot have a good sex life, if he chooses to. We have all seen the advertisements for testosterone. While “low T” is a problem for some men, it is not common, and improving a man’s testosterone will not improve his erections.

Erection is all about blood flow to the penis, so conditions such as high blood pressure, heart disease, diabetes and obesity are frequently associated with difficulty obtaining and maintaining an erection. First, make sure any of these issues is managed as well as possible. Something as simple as losing weight can improve erections.

Make sure your blood sugar is in the ideal range, and if you are on drugs to control high blood pressure, be sure to take them as prescribed. There are also drugs that improve blood flow to the penis, such as Cialis, Viagra and Levitra. These all work by improving blood flow to the penis and are very safe except in men who are taking nitroglycerin or similar drugs.

Men want to know if one is better than another. The answer is no. They all have about equal efficacy. They only difference is that Cialis takes longer for the body to metabolise, so its effect lasts longer than the others. Unfortunately, these drugs are expensive, but there should be generic equivalents available in the not too distant future.

If these drugs are not effective, there are other options. Injecting small amounts of drugs that improve blood flow directly into the penis with a tiny needle — much like a diabetic does with insulin — is highly effective. This needs to be done under the direction of a urologist, but it is safe, effective and much cheaper than the oral medicines.

Finally, there are surgical options, with penile implants. We generally reserve this as a final solution for men who have failed other treatments, but the satisfaction rate of men who choose this is greater than 90 per cent. Discuss it with your urologist.

Like anything else worthwhile, staying healthy takes commitment and hard work. Only you have the power to do it. Be a man.

•Michael P. O’Leary, is the Professor of Surgery at Harvard Medical School and the Senior Urologic Surgeon at Brigham and Women’s Hospital in Boston