According to experts, even nutritious foods packaged in new and improved ways could be bad for the health in the long term if one does not carefully read the labels, reports ABCNews.com. Traditional foods in new forms, from peanut butter sliced like cheese, to the dozens of forms of soy products, or portable yoghurt eaten out of a plastic tube, can have decreased nutritional value, and sometimes, more calories and fat than whole grains, and unprocessed fruits and vegetables. Dr. James W. Anderson, a professor of medicine and clinical nutrition at the University of Kentucky , in Lexington, believes the easier any food is to prepare, carry and eat, the more likely you are to eat it. "Processed foods contribute to weight gain," Anderson said. "I think that consumers need to be more sophisticated. If you are concerned about fat, less than 30 per cent of your calories have to come from fat." According to Joanne Larsen from Dietitian.com, people tend to grab fatty foods on the go, because they are easy to eat, provide quick energy, and can trigger the brain's "feel-good response to carbohydrates." "Convenience packaging can help increase consumption of nutritious foods like yoghurt or milk as well as high fat, high sugar foods," she added. "Consumers should look at the nutrient content on food labels. Protein should [account for] between 10 and 20 per cent of calories [consumed in one day], fat around 20 to 30 per cent, [and] carbohydrates filling the remaining 50 per cent," said Larsen. "Good sources of protein should come from milk, egg or soybean and may be listed as casein, whey, albumin, egg white, yolk, or soy protein and should be the first or second ingredient. If sugar or corn syrup solids is listed first, then the bar is just a candy bar in disguise," she says. New and different food forms, such as the tube yoghurt and candy-like bars infused with protein, can be good ways for people on the go to pack in important nutrients. But don't overdo it, say the experts. Many processed foods contain more nutrients than raw foods due to enrichment or fortification. "Not all processed foods are bad for you, just [the ones that are] high fat, high sugar processed foods, which should be limited to infrequent use," Larsen says. One of the most popular and malleable food sources today is soy. Nutritionists say soy isoflavones have qualities that could reduce risks of heart disease, problems related to osteoporosis, breast and prostate cancers, and possibly some additional benefits for pre-menopausal women. Nutritional experts say people can get the benefits of soy by consuming about 25 grams of soy protein a day. Although food labels usually do not give an exact amount of soy protein, Dr. Anderson says it 25 grams is roughly a handful of soy nuts, or a scoop of soy protein powder. Dr. Anderson advises products that have "isolated soy protein" listed on the label's ingredients rather than "soy concentrate," because isolated soy protein products are washed with water and retain up to 90 per cent of the isoflavones and other healthy properties. However, some products use soy protein concentrate, which is purified with alcohol to take away some of soy's "off-putting characteristics," such as upset stomach.