My dentist tells me that my plaque build-up is due to age-related blood chemistry changes. I am 68. How will these changes affect my cardiovascular health?

A Plaque depends mostly on bacteria in the mouth, the volume and pH of saliva, and how well you’ve cared for your teeth and gums. Ask your doctor for a blood test to check your biochemistry. The main correlates for cardiovascular risk are with high blood pressure, smoking, high cholesterol, poorly controlled diabetes, obesity and lack of regular aerobic exercise. Your mother and her siblings may have differed from you in all these, so you cannot relate your risk to theirs.

Q My wife has postnatal depression after our first baby. We have lots of support and she is recovering slowly, but we’re worried about what may be ahead. How long will she be depressed, and will it return?

A Most women with postnatal depression who respond to treatment recover completely. Some are susceptible to depression after childbirth: they have around 40 per cent risk of another depressive episode after subsequent pregnancies. They have a lower-than-usual risk of becoming depressed outside the context of pregnancy and birth. On average, postnatal depression lasts three to six months, although some women have a low mood for a year or more. Follow your doctor’s guidance in the meantime.