JUNK food does not exist, says Professor Stanley Feldman. “Of course, some foods taste better or are more nutritious. But the idea that some contain nothing of value or are harmful is nonsense.”

For Professor Vincent Marks, junk food is “a contradiction in terms. By definition, food is good for you. The only bad food is food that has gone bad. McDonald’s is considered bad, simply because it is wrong for the current fashion.”

These two views may seem unusual. We are used to warnings about burgers, fizzy drinks and other fast foods, and high fat, sugar and salt content being blamed for an epidemic of obesity, especially among children. The Department of Health has detailed targets for reducing consumption of what it calls “unhealthy foods” (aka junk). One MP has even introduced a Bill to ban junk food adverts from children’s TV. There is also a huge amount of anti-junk food literature, from Eric Schlosser’s investigative Fast Food Nation to the children’s morality tale, The Berenstain Bears and Too Much Junk Food. But much of this orthodoxy is rejected as unscientific by Feldman (from the University of London) and Marks (Surrey University). They carry no banners for the fast-food industry, and it is hard to imagine them eating a double cheeseburger, but they object to what they see as “misinformation” and “propaganda” from the anti-junk food lobby.

“The idea that any food by itself is harmful is nonsense,” Feldman says. “Meat is not absorbed into the blood stream as Angus beef or Big Macs, but as a variety of amino acids, the same in both meats. Fat enters the bloodstream as fatty acids, and the same ones are produced from good cheese as from fatty meat.

“In a balanced diet we need a certain amount of protein, fat and carbohydrate. We also need salts. One thing that might be considered as ‘junk food’ is water, since it has no nutritional value, but we can’t survive without a certain amount of that, either.”

Obesity, Feldman thinks, “is not down to one type of food, or to one make of food”. The suggestion that fatty or sugary foods are addictive is “absolute nonsense. They say that these foods release endorphins in the body. Well, a lot of things do that — sex, sunshine, laughing. Are we supposed to ban them as well?”

Marks first upset food faddists when he identified a condition that he called Muesli Belt Malnutrition. He thinks that junk food is “just an emotive, derogatory label that means you don’t approve. My mother thought that baked beans on toast with tomato sauce was junk food. Now we might say it is ideal, lots of antioxidants, fibre and so on.

“Food that is eaten is good for you. I have been trying to get the manufacturers to make ice-cream with all the minerals required for feeding people in hospital, because it is one thing that they will eat.”

Warnings about addictive fast food are “a distortion of the concept of addiction. You might as well say that all food is ‘addictive’, since we keep going back for more, especially the ones we enjoy.”

Marks accepts that “obesity is a big problem. But it is much more complicated than we have imagined, probably with genetic and biological factors. People do need to be educated to understand that while there are no rigid rules, there are general guidelines. But to label these foods as the problem is just to try to find a scapegoat.”

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