May 2, 2005

Dr Dean Ornish, advocate of low-fat diets, comments on his work as paid consultant to McDonald's Corp; many leading nutrition scientists have started working for large food companies, either as consultants or members of health advisory boards, in recent years as companies face increased Congressional scrutiny and threat of suits over diet-related illnesses; Ornish and others defend their controversial dual roles as efforts to improve American diet from within; photos (M)

Horses in 131st running of Kentucky Derby are being tested for illegal performance-enhancing drugs, as horse racing industry finally acts on decades of rumors about 'juiced' thoroughbreds; C Steven Duncker, chairman of Thoroughbred Owners and Breeders Assn's Graded Stakes Committee, has mandated increased post-race testing for Derby and other important races in United States; ability of racing authorities to police industry has been hampered by its patchwork of regulatory agencies; industry has no national standards, and states set their own policies; Kentucky, home of thoroughbred breeding industry and Derby, most famous two minutes in sports, is among most permissive when it comes to drug policy; increased surveillance and testing at Churchill Downs this year comes after positive test results in horses in California and federal indictment of New York trainer; description of various illegal ways to enhance performance of racehorses; photo; chart (M)

IN the steroids scandal that has turned baseball into chess, Commissioner Bud Selig made a daring move Saturday: a proposed 50-game suspension for a first positive test, a 100-game ban for a second and a permanent ban for a third. Selig also wants to add amphetamines to the major leagues' list of banned substances. Across the chess board, Donald Fehr, baseball's union leader, is contemplating his next move as if he were Rodin's ''The Thinker.''

Profile of and interview with Paris Hilton, who says she is ready to leave partying scene and focus on her career; Hilton is starring in remake of 1953 film House of Wax, has changed publicity firm to Dan Klores Communications, has parted ways with Nicole Richie, co-star in hit Fox series The Simple Life, has started fragrance and makeup lines and has joined forces with Fred Khalilian in opening nightclubs, first of which is Club Paris in Orlando, Fla; photos (M)

Outlook for stock of Amazon.com, online retail giant, discussed; some analysts expect further drop in profits over next few quarters as company focuses on developing newer business areas; chief exec Jeff Bezos points to longer-term perspective, noting several recent customer-oriented initiatives that will not pay off for years; graphs of stock price, revenue and income (M)