* LIVE NOW, AGE LATER: Proven Ways to Slow Down the Clock

By Isadore Rosenfeld, MD

Warner Books, New York

384 pp.; $24

What have we here? A health how-to book with heart? A well-written, authoritative medical guide honest enough to admit that though healthful living can help control the aging process, it cannot stop it--and indeed, in some cases, cannot even slow it down?

Hard to believe maybe, but to this--alas--experienced patient, the answer seems to be "yes." And I'm sure the author, a well-credentialed practicing physician, health editor and occasional television talking head, would agree with me. For he is not shy about his talents or even his persona--advising readers to examine his picture on the book jacket to see if he looks a day over 50. (He does, though he looks nice, like a waggish uncle.)

The book's large type and clear, bold-faced section heads make it user-friendly. Arranged alphabetically, it leads with chapters on "Alzheimer's Disease" and "Cancer" and ends with "Tooth Loss" and "(Loss of) Vision." I particularly appreciated the author's close attention to the more mundane ailments (like loss of libido and constipation), which may not be life-threatening but can lower your quality of life and leave you feeling pretty miserable, as well as to the serious illnesses like heart disease, stroke and cancer commonly afflicting older people. (Though most do not realize it, older Americans are 10 times more likely than younger people to develop cancer, but are screened less often, referred less frequently to major cancer centers and usually treated less aggressively.)

Many readers will want to browse through the book according to their special concerns. Others--and I was one of them--will enjoy Rosenfeld's sensible guidance throughout, and even the medically sophisticated can learn a good deal. From the chapter on insomnia, for instance, you find that mammals vary considerably in their sleep patterns: Whales nod off while swimming; horses and elephants can sleep standing up; and some animals--including some of Rosenfeld's students--doze with their eyes wide open. Rosenfeld, who is a cardiologist and a professor of medicine at New York Hospital Weil Cornell Medical Center, is cautious about--but not afraid of--prescribing sleeping pills, including Halcion, for a maximum of three weeks if warranted, though he doesn't cotton to over-the-counter antihistamines as a sleeping aid. And according to the chapter on depression, Zoloft is his favorite antidepressant, though he suggests trying Saint Johnswort first.

Don't be put off by some unbearably cutesy chapter subtitles, such as "To Pee or Not to Pee--That Is the Question" (for prostate enlargement) or "This Chapter Will Really Move You" (for constipation). There's too much of value inside these chapters, including careful descriptions of the ailment under discussion and what is known about its risk factors, prevention, symptoms, diagnosis and treatment.

I am sure experts could find bones to pick with some of the author's statements. For instance, having read another "clock/aging" book explaining that though our eyes and ears lose specific capabilities as we age, our senses of taste and smell don't change at all, I was surprised at Rosenfeld's more clinical description of how older people (himself included) flavor everything they consume because of the decreased acuity of these senses. Also, some would question his "keen" espousal of hormone replacement therapy, whose benefits to menopausal women he feels outweigh the risk that estrogen poses for breast cancer. And I would add that in his chapter on menopause he has little advice for cancer survivors for whom estrogen is forbidden.

Unlike some of his colleagues, Rosenfeld is respectful of complementary therapies that might help and don't hurt you. He also at least mentions the inequities in our health care system, which keeps the less affluent from the hearing aids they need and fails to ensure bone density tests for those vulnerable to osteoporosis.

If he waxes a bit over-eloquent about the benefits of exercise or the glories of high flyers John Glenn and George Bush (sorry, not for me, boys), he can be forgiven. Would that every non-pediatrician were as interested in geriatrics and took--or was allowed to take--the time not simply to flood us with medical information but to walk us through it, explaining both the powers and perils of modern medical practice.

Natalie Davis Spingarn is the author of "The New Cancer Survivors: Living With Grace, Fighting With Spirit."