What’s lurking on supermarket shelves, hiding in refrigerators and, in some cases, disguising itself as good for you? Food demons — as in, the five food felons you should avoid, according to Michael F. Roizen, MD, the chief wellness officer at the Cleveland Clinic and co-author with Mehmet Oz, MD, of the best-selling “YOU!” books. “These five food felons have no redeeming social value, and they cause aging,” says Dr. Roizen.To stay healthy, you need to look for these felons in the ingredients of your favorite foods — and avoid them. “If they show up in the first five ingredients (excluding parentheticals), don’t eat them,” he says. Without these felons in your diet, you can significantly lower your chance of disease and premature aging.

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1. Trans Fat

Trans fat is number one because it’s the worst of the bunch. “Trans fat is poison for your body,” says Dr. Roizen. Also called trans fatty acid, it’s most often found in cookies, crackers, chips and in many foods cooked at fast food restaurants — especially fried foods. What makes it so bad? Trans fat alters metabolic processes and increases the hardening (and thus aging) of your arteries. Studies show that the more trans fat a person eats, the faster the cardiovascular system ages.

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Be careful when looking for trans fat on food labels, since the label may not actually say trans fat. Watch for the words partially hydrogenated vegetable oils. And if you spot a label that says it has zero grams of trans fat, don’t necessarily believe it: In the United States, if a food has less than 0.5 grams of trans fat per serving, the food label can read 0 grams trans fat. While that’s a small amount, if you eat multiple servings, it’s easy to consume too much. If partially hydrogenated vegetable oil or vegetable oil blend is near the top of the ingredient list or is listed before healthy monounsaturated and polyunsaturated fats, the product most likely contains plenty of the bad stuff.

2. Saturated Fat

Unlike trans fat, which is created artificially, saturated fat occurs naturally. But that doesn’t mean it’s good for you. Saturated fat ages your arteries by causing the buildup of fatty tissue on their inner linings. Found in red meats, full-fat dairy products, palm and coconut oils, and to a lesser extent in poultry skin and other animal products, saturated fat makes it easier for the level of bad cholesterol to rise in the bloodstream. Interestingly, “there is actually a safe amount of saturated fat you can consume,” says Dr. Roizen. “The problem is that this safe amount is quite small — four grams in an hour.” So why avoid saturated fat altogether? “Because people don’t do moderation,” explains Dr. Roizen. “That means eating a four-ounce lean pork tenderloin. And that’s it, fatwise, for the meal.”

3. Added Sugar

There are two main types of sugars — sugar that occurs naturally in foods like milk, vegetables and fruits, and refined sugar (aka simple sugar), which is added to foods for sweetness. Added sugar is any sugar that does not naturally occur in the food. Extra sugar causes the proteins in your body to be less functional and, as a result, directly ages your immune and arterial systems and even your joints (hello, arthritis). “The bad effects last a lot longer than the joy of the food,” says Dr. Roizen. “The joy of the food might last 10 minutes. The protein change lasts months.”

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A food is likely to be high in added sugar if one of the following substances is first or second in the list of ingredients (or if several of them are present): brown sugar, corn sweetener, dextrose, fructose, fruit juice concentrate, glucose, honey, invert sugar, lactose, maltose, molasses, raw sugar, sucrose, table sugar. Also watch out for concentrated fruit juice and expeller pressed organic rice extract. “All are really just sugar,” says Dr. Roizen. As for agave, neither is it any healthier than all of the other added sugars. The only difference is that agave offers more sweetness in smaller doses, so it’s a good way to reduce consumption.

4. Syrups

When it comes right down to it, a sugar is a sugar is a sugar. Which means that syrups — corn, maple, malt and others — are as bad for you as the other added sugars discussed above. High-fructose corn syrup (HFCS) is a man-made sugar that does the same things as sugar, including increasing risk of obesity and metabolic syndrome. Metabolic syndrome is a cluster of conditions — including increased blood pressure, elevated insulin levels, excess body fat around the waist and abnormal cholesterol levels — that occur together, increasing your risk for heart disease, stroke and diabetes. Unfortunately, HFCS can be found in a wide range of processed foods, from ketchup and cereals to crackers and salad dressings. It also sweetens just about all of the (regular) soda Americans drink.

5. Any grain but 100% whole grain

Whole grains are grains that have not been stripped of their outer layers, the source of many key nutrients, and haven’t been refined, which means they retain most of their vitamins and minerals. Whole grains contain a lot of fiber, which is important for preventing arterial aging and reducing the risk of cancer. The problem is that unless the bread or pasta you’re eating is made from 100 percent whole grain (and says so in the number one spot in the ingredient list), it’s not much better for you than white flour products that have been stripped of the healthy outer shell and germ, says Dr. Roizen.

When you eat these products (breads and pastas made with enriched, bleached, unbleached, semolina or durum flour), your body quickly converts this carbohydrate to sugar in your bloodstream and we’re back to the same health problems you get from consuming added sugars. One-hundred percent whole grains, meanwhile, take longer to convert to sugar and also stay in your intestines longer, which means you stay fuller longer.— by Eileen Livers