This book is based on the premise that, to quote the dust jacket, ‘only about 25% of elders meet the standards for optimal cognitive aging’. This is seen as a bad thing, and the book devotes itself to exploring why this is so and how it can be amended. There are strengths and weaknesses both to this argument and also the way it is presented. First, the readership is intended to be older adults, their carers, and health professionals. I would advise caution before giving this book to many older adults. Those reading it might be reminded of report cards from school with the dreaded words ‘could do better’ summarising their performance. Even though the author makes a considerable effort to strike a positive tone throughout, the weight of evidence about age-probabilistic conditions and their effects makes for depressing reading at times. Furthermore, whilst not alienating, many of the anecdotes given by the author will not resonate with people outside the middle classes of the USA. Tales about tennis playing are perhaps okay, but descriptions of flying to college alumni reunions will be an experience few in, for example, Europe will have. Likewise, the idea of the pastor of the local church offering to intervene in a marital problem might be common in middle America, but less so in many more secular countries.

I would also be cautious about recommending the book to health-care professionals. In part this is because of the referencing system used. Some (but far from all) key points are referenced using footnotes (at the back of the book) that offer more discussion and a referenced publication. This might be fine for a casual reader, but for anyone with prior knowledge of the area, having to keep going to the back of the book and wade through expository text to find the reference, this is irritating. This might sound like a petty point, but in actually reading the book it is likely to prove to be a major stumbling block. More pertinently perhaps, a considerable proportion of the work referenced is ten or more years old. A lot of the assumptions made by the author from this work were not necessarily universally accepted at the time, and have been in some cases contradicted or at least qualified by more recent research.

These caveats aside, the book has its strengths. Provided you are unconcerned about checking every reference, the book is very readable and, as mentioned, tries to create a positive note. I particularly liked the author's anecdotes about his own health – it shows a level of warmth and humanity that books of this kind often ultimately lack. The information given on how to improve your lifestyle (cognitive and physical) is also in the main eminently sensible. Anyone who has heard this advice too many times in the course of their professional work might get a bit blasé or cynical (at the end of one list of desiderata I found myself scribbling ‘and don't run with scissors either’), but for others this could (literally) be life-prolonging. And the research-based arguments, even if they are predicated on slightly dated material, are still generally sensible in arguing that people should try to keep mentally as well as physically active.

We should perhaps at this point raise the argument about what is meant by ‘optimal’ ageing anyway? Strictly speaking, optimal cognitive ageing means attaining the maximum possible cognitive skills. On the surface this sounds wonderful: the idea of allowing everyone to reach their best is difficult to contradict. But taking this one factor in isolation ignores a crucial point: not everyone will be happiest if they are intellectually stretched to their limit. We need to balance considerations of intellectual stimulation with concepts such as need for cognition and other personality variables. The same applies to physical exercise and many other desiderata taken as touchstones of modern health and social care. Some people might be perfectly happy when not pushed to their limits. They might live slightly shorter lives, but arguably they will be happier ones. I think the author might perhaps have examined this point in a little more detail.

I am reminded of the dreadful joke about an old couple who die and go to heaven. St Peter shows them around – there is no pain, constant pleasure, every possible fun activity imaginable, 24/7. The man turns to his wife and says ‘if you hadn't made me go jogging and eat all those revolting bran muffins I could have enjoyed all this years ago’. It is one thing to have a healthier lifestyle – but if it makes the person unhappy, what use is it?