Dear Readers:

Elton John sang that “Sorry Seems to Be the Hardest Word,” but for me the hardest word is “Goodbye.”

Every goodbye is an ending. Long before life ends, individual pieces of that life end. Many of those little endings are the close of something you cherish — something that brought meaning or pleasure to your life.

Today’s column will be my last. I’ve been writing this column for over five years. At age 75, I’ve decided to slow down. The time required to write a column six days a week, 52 weeks a year, makes that hard.

Even though this is the right decision for me, I regret having to make it. Your questions have been interesting and remarkably wide-ranging: “Is it safe to swaddle a baby?” “How does Alzheimer’s wreak so much havoc in the brain?” “When we lose memories, do we lose them forever?”

I doubt you assumed I was an oracle who could just write the answer to every question off the top of my head. Indeed, I leaned heavily on the knowledge of many colleagues at Harvard Medical School, and I did my homework. I learned a lot, and I hope I was helpful to you.

Above all, I love the process of trying to clearly explain things that can be pretty complicated. I tried to do that for the more than 1,500 columns I wrote. Each one gave me pleasure. And your letters and emails thanking me for my efforts added greatly to that pleasure.

Were there any themes that ran through my columns? There were at least two. The first is that, through the lifestyle we choose, we can do more to improve our health than anything our doctor can do for us. For example, through lifestyle we can reduce our risk of getting Type 2 diabetes (the most common kind) by nearly 70 percent. No medicine yet invented can do that.

The second theme is that we need to do more to support biomedical research. Most of that support comes from our federal tax dollars. Biomedical science has progressed so rapidly in the past 50 years that we have the power to make major advances. Yet there is not enough money in the budget to fund many worthy projects, slowing progress. Who decides how much money is spent on medical research in our democracy? We, the people.

Although today’s column is my last, I’m pleased that three members of the faculty at the UCLA School of Medicine will be starting a new column, “Ask the Doctors,” which will appear in the many papers where my column appears. This closes a circle for me, since I grew up practically next door to that prestigious institution.

I want, in particular, to thank Urmila Parlikar, who has helped me to gather and organize information for this column with remarkable skill and dedication. In addition, Alan McDermott and Shena Wolf, the column’s editors, have added elegance and clarity to every column.

I will miss you, and miss writing for you. Thank you again for all of your kind words over the years. And goodbye.

Dr. Anthony Komaroff can be reached at www.AskDoctorK.com.