DEAR DR. ROACH: I read your recent column about using the immune system to prevent cancer, but I think that there will never be a “vaccine” to prevent anyone from getting cancer in the first place! There is too much money involved.

• D.K.

ANSWER: I hear this occasionally, and I don’t believe it for two reasons.

The first is that I have faith in the researchers across the globe who are working to improve our knowledge of cancer biology. They have incrementally improved our ability to treat and, in many cases, cure cancer. As of 2026, 70% of people with newly diagnosed cancer will be alive in five years, and many of them will never get recurrences of their original cancer. (However, since age is the major risk factor in getting cancer, it is likely that some people who were cured of their original cancer will later succumb to a different one.)

The idea that a cure or preventive for cancer would be developed, then never get used just doesn’t make sense to me. I don’t think there is enough money in the world to buy the silence of the researchers, doctors and scientists who are making these discoveries. I personally know enough of these experts to say this confidently.

The second reason is that we already have at least one very effective cancer vaccine. In men, the HPV vaccine helps prevent head and neck cancer. Also, the HPV vaccine prevents cervical cancer to a very high degree. In a country like Australia, which has an excellent uptake of the vaccine, it is expected that there will be no more cervical cancer by 2035.

DEAR DR. ROACH: I was talking to my friend the other day. He is in his late 60s and stated that he had lost 2 inches in height over the past couple years. I am in my mid-70s now and want to know what causes the loss of height and if there is a way to stop it or reverse it.

• W.T.

ANSWER: There are two main physiological reasons that we lose height as we age and one pathological reason that your friend should consider. The main physiological reason is that in our spines, the discs between the vertebral bodies (intervertebral discs) tend to lose water and flatten out as we age. This is responsible for most of the 3 centimeters that men lose on average between ages 30-70. Women lose 5 centimeters.

The second physiological reason is in your feet; they flatten out as the arch partly collapses. You may have noticed that you wear slightly longer shoes than you used to.

Readers may email questions to ToYourGoodHealth@med.cornell.edu.