TO YOUR HEALTH : BOOKS.

``The Portable Pediatrician's Guide to Kids,'' by Dr. Laura Walther Nathanson (HarperPerennial; $20). Plenty of advice books are available for the parents of babies, but where do you turn when the toddler is suddenly a 10-year-old? From the author of ``The Portable Pediatrician for Parents'' comes this installment, a guide to the physical and behavioral development of children ages 5 to 12. Nathanson, a California pediatrician and mother, says those middle years are when children develop a self-image, a sense of their ``ideal self.'' The book is divided into three age categories: 5-6; 7-8; and 9-11. Each segment discusses not only what to expect physically of a child that age, but also what to look for emotionally, academically, socially and morally.

Freebies

Five servings of fruits and vegetables is the recommended daily intake for people who want better health. Folks with the International Apple Institute offer up apples - which have 0 grams of fat and 5 grams of fiber - as a way to meet that goal. The institute has put together ``Apples: Well on Your Way to `5 a Day' for Better Health,'' a free brochure with tips on how to select, store and squeeze apples into your daily menu; it includes two recipes. For the brochure, send an addressed, stamped, business-size envelope to: Apples and 5 A Day Brochure, IAI, P.O. Box 1137, McLean, Va. 22101-1137.

A free source of up-to-date medical information on strokes is now as near as your local Blockbuster Video store. In ``Brain Attack! A New Way of Looking at Stroke,'' Jack Lemmon and Patricia Neal spend 28 minutes describing the causes, warning signs and latest methods of preventing and treating a stroke. The video, produced by the Center for Stroke and Cerebrovascular Disorders at USC University Hospital and the National Stroke Association, is lent out free as a Blockbuster Video public service. For more information about the stroke program at USC University Hospital, call [phone]. For more information from the National Stroke Association, call [phone].