Not only did Atkins have the charisma to communicate his ideas successfully, but he also was flexible enough in recent years to moderate his views. He collaborated with noted dietitians and nutritionists to help Atkins followers maintain their hard-fought weight-loss successes in a nutritionally wise way, Blackburn said.
"I think his final book on maintenance might have been his finest," Blackburn said. "It showed he was not fixed in ideas that he developed 30 years ago; that he was ready to change."
For example, he said, it advocated eating nutrient-rich vegetables and "meats other than those that are red and saturated with fat."
Atkins was born Oct. 17, 1930, in Columbus, Ohio. He graduated from the University of Michigan in 1951, and four years later received his medical degree from Cornell University Medical School. After completing a cardiology residency at St. Luke's Hospital in New York City, he opened a private practice in 1960. In 1984, he expanded that practice into complementary medicine, stressing lifestyle and longevity.
In 1993, Atkins' alternative medicine practice, which included prescribing ozone for cancer and AIDS, made him the target of a complaint to New York state health authorities. Although he lost his medical license, the New York Supreme Court ordered it reinstated.
In 1997, Atkins and his wife, Veronica, published "Dr. Atkins' Quick & Easy New Diet Revolution Cookbook," and that same year, Complementary Formulations launched a line of low-carbohydrate "Atkins Advantage" foods. In 1998, he released "Dr. Atkins' Vita-Nutrient Solution: Nature's Answer to Drugs," in which he proffered advice on using vitamins, minerals, herbs and other supplements to prevent and treat many chronic conditions. In 1999, he established the nonprofit Dr. Robert C. Atkins Foundation and published "Dr. Atkins' Age-Defying Diet Revolution," in which he discussed the chemicals in fruits and vegetables as well as the nutritional supplements that might help retard aging.
In April 2002, Atkins suffered cardiac arrest during breakfast and had to be revived. He spent a week in the hospital, and upon his release said he had not suffered a heart attack but instead suffered the effects of an infection unrelated to his diet.
The Atkins brand recognition got a boost not only from his books, but from the foods, snacks, energy bars, beverages and supplements sold through his Web site. He lectured widely and hosted a radio show in New York.
In addition to his wife of 15 years, Atkins is survived by his mother, Norma of Palm Beach, Fla. He had no children.