British media said the latest study found that eating junk food will kill the gut bacteria that can ward off obesity, diabetes, cancer, heart disease, inflammatory bowel disease and autism. According to the British “Daily Telegraph” website reported on May 10, there are about 3,500 strains of bacteria in the human intestine, with a total weight of about 3 pounds (1 pound is about 0.45 kg). Scientists now believe that a daily diet based on a limited variety of highly processed foods can reduce the number of intestinal flora by more than a third. This finding could explain why some people gain weight while others do not, when consuming roughly the same amount of fat, sugar, protein and carbohydrates. This is the research of Tim Spector, professor of genetic epidemiology at King’s College, University of London. He convinced his 23-year-old son Tom, who is studying genetics, to assist, and Tom agreed to eat only McDonald’s burgers, fries and chicken nuggets and drink Coca-Cola for 10 days straight. Tom said, “Before I started eating fast food every day as my father wanted, I had about 3,500 strains of bacteria in my intestines, mainly thick-walled bacteria. After eating fast food, I quickly lost 1300 strains of bacteria, and my intestines were dominated by anthropoid bacteria. This means that McDonald’s food killed 1,300 strains of bacteria in my gut.” Two-thirds of adults in the UK are overweight. Professor Spector’s results seem to corroborate existing research findings that the problem is far from as simple as eating too much. Intestinal flora also play a key role in guarding against potentially harmful microbes and regulating metabolism. They synthesize vitamins A and K along with digestive enzymes that help the body absorb important minerals, such as calcium and iron. An imbalance in flora increases the likelihood of colitis and inflammatory bowel disease. There is also evidence that autism may be associated with low intestinal bacterial activity. Bacteria have a bad reputation, but of the millions of strains, only some are harmful and many are vital to our health,” said Professor Spector. It is becoming increasingly clear that the human gut microbiota may be responsible for obesity, diabetes, cancer and heart disease.” He emphasized that in terms of a healthy diet, eliminating fat and sugar is better than ensuring that foods are as diverse and natural as possible. In line with his advice, studies have shown that Belgian beer, garlic, coffee, leeks and celery are ideal foods for promoting healthy gut flora. Professor Spector notes, “Fifteen thousand years ago, our ancestors typically ate 150 ingredients per week; today, most people consume fewer than 20 ingredients, and many have been artificially refined. Most processed foods use only four ingredients: corn, soy, wheat and meat.”