The downfall of the Swedish government, according to some accounts, began with artificial food colors. Of course, the defeat last year of the Social Democratic party, which had been in power for 44 years, was based on a number of complex issues, particularly nuclear power. But the environmentalists who are credited with the change in government began their public-interest work with a call for a ban on coal-tar dyes.

Their leader, self-contained 38-yer-old Dr. Bjorn Gillberg, often described as Sweden's Ralph Nader, is the founder and director of the environmental group Miljocentrum - Environment Center.

Gillberg's involvement with environmental problems began in the late '60s when publication of his controversial book "Threatened Generations," which charged government mishandling of environmental and consumer issues, thrust the scientist into the limelight, Gillberg, a geneticist, said he had tried "discussing these problems with the government but nothing happened, so I decided to raise hell about it."

Nader's efforts brought harassment from General Motors. Gillberg said his resulted in the Swedish government's refusal to renew his research grants at the University of Uppsala. But there was "a very violent response in the mass media, demanding explanations," Gillberg said rather matter of factly, and when the news was published financial contributions from the public poured in. With this support Miljocentrum was founded. Today two-thirds of its funding comes from the public; one-third from foundations.

Looking back, Gillberg, who did not betray a hint of emotion beyond an occasional smile in an interview at a recent conference here on saccharin, said having his research money cut was "the best thing that could have happened."

One of the center's first project was to start a campaign to rid the Swedish food supply of the coal-tar dyes that such as bread, meat, fruit, cheese and butter. "Coal-tar dyes are banned," he said, "but are still being phased out. Mainly you find them in junk foods, like soft drinks, but they are disappearing from those products, too. Natural colors are being substituted."

Baby foods in Sweden are free of artificial color and monosodium glutamate (neither is found in American baby food today) and contain less sugar than they did before Gillberg's efforts.

Miljocentrum also launched a campaign against canned baby foods and formulas. The center put out booklets on breast feeding and alternatives to commercially prepared baby foods, both of which were best sellers.

Gillberg said there has been some improvement in school lunches because of the center's work. "The worst products have disappeared, especially the strange synthetic ones, but there are too many prepared foods.

"Hospital meals are still of very low quality," he said. He blames the doctors. "The medical profession doesn't understand the relationship between nutrition and health."

On the other hand, he said, the Swedish medical community has not opposed a national nutrition policy, very similar to the Senate Nutrition Committee's Dietary Goals for the United States that have come under attack from the American Medical Association.

Referring to Sweden's highly centralized Socialist form of government, he said: "One of the things with a Big Brother Society is we have very good records. The Big Brother Computer tells us how many drugs were prescribed, how many days someone was sick. When you analyze the records, much sickness has to do with food habits. The health-food people, the people whose diets are dominated by vegetable products, free of additives, etc., had much better health records.

"There is a lot of scientific evidence," Gillberg said, "to back up the idea that people who eat healthy food live longer.

"Roughly 50 per cent of the Swedes die from cardiovascular disease; 30 per cent die from cancer. Something drastic has to be done. There is too much sugar, too much fat. Chemicals cause maybe 80 per cent of the cancers.

"We spent billions of dollars in 10 years building big fancy hospitals and laboratories but the Swedes have never been in worse shape," in Gillberg's view.

While the medical profession may not have criticized the national nutrition policy, Gillberg does because it bypasses the issues of pesticides and additives and because the government spends only $250,000 a year on nutrition education.

The Swedish food supply still contains potentially hazardous additives, in particular, sodium nitrite which Gillberg's group has fought to get rid of. Their campaign was more effective in neighboring Norway where the chemical was banned completely in 1971. Nitrites, which combine with other substances to form a cancer-causing agent when fed to test animals, are used to flavor, color and preserve meats. Gillberg seems confident that nitrites will be "banned in Sweden sooner or later."

And sooner, rather than later, Gillberg expects the government to remove saccharin from foods and beverages and sell it only in powder form. While he was in Washington Gillberg received word that Sweden's equivalent of the U.S. Food and Drug Administration would be meeting in November and "will probably ban saccharin."

"Our activities caused a lot of problems," he said. "Companies went bankrupt and people were out of jobs."

But today, much of that has changed: "Companies which were criticizing us are now running ads to say their products are free of colors and additives. The attitude in the country has changed drastically. Companies realized they could make money listening to us."

What Gillberg has learned about diet and health has had a profound effect on his family's lifestyle. "We made drastic changes. I am not smoking and my wife is not smoking. Our meals are odminated today by vegetable products, fruits, beans, peas. We feel much healthier. I know that's a subjective judgment," he added, "but we are also saving a lot of money. Our budget for food today is lower with three children than it was 15 years ago when we got married."

Gillberg has discovered, "If you tell the people the companies are cheating them and poisoning them at the same time, they listen." But even he has been surprised at the overwhelming response of the public to his crusade for a cleaner, healthier environment. He warned that the tremendous support his activities have had in Sweden cannot be expected in a country as large and as diverse as the United States. "Sweden is a small country. It is one ethnic group. It has the highest education standard in the world and it is very centralized. You can reach everyone in Sweden on the two television channels. And there are no television commercials."

Even with all his success. Gillberg feels the situation "will get much worse in Sweden before it gets better." He explained: "It takes 20 years or more for cancer to develop. The chemical explosion, the chemical jungle, was really growing up in the '60s. So in the '80s and '90s the number of cancer victims will increase."

Because of Gillberg and others like him who have publicized the dangers of chemical additives, the consumer movement is developing all over Europe. According to Gillberg, "the movement is growing larger every year."

And what about the future of Miljocentrum? "My goal," he said with a smile, "is to eliminate the need for this kind of organization."