New thinking: In truth, any food consumed in too great a quantity will cause weight gain. However, when eaten in appropriate portions — always check the serving size as a guideline — the protein and healthy fats found in nuts may actually help you lose weight. In addition to weight loss, eating nuts has been associated in several studies with reducing the risk of heart attack and stroke. Walnuts, which contain heart-healthy omega-3 fats, are a particularly good option.
Old thinking: It’s a sweet treat, so it must be bad.
New thinking: The old thinking does apply to chocolate treats with a lot of added sugar. However, dark chocolate — look for cocoa content of at least 70 percent — is loaded with flavonoids, the same beneficial compounds found in berries, red wine and tea. An ounce of chocolate a day has been shown to reduce risks for heart disease, and an ounce and a half may help reduce stress.
Old thinking: All potatoes are too fattening.
New thinking: Certain potatoes may play a role in reducing the risk of a silent killer — but the type of potato matters. A 2012 study found that purple potatoes helped lower blood pressure in hypertensive, obese individuals without causing weight gain. Additionally, potatoes are naturally high in fiber and contain virtually no fat. Sweet potatoes and purple potatoes are tops when it comes to nutrient density, but what you put on your potato (or don’t put on it) will make or break an attempt at a healthy meal. Forgo the sour cream, bacon bits, butter and cheese. Opt for fresh veggies and herbs instead.
Old thinking: Eating soy increases your risk of disease.
New thinking: Soy is certainly controversial, but as with some of the foods mentioned above, the type of soy you eat matters. Many concerns are associated with highly processed soy products, but numerous studies looking at isoflavones and protein in whole soy sources — think miso, tofu and edamame — demonstrate the benefits associated with this legume. Highlights include reduction in cancers of the breast(for women on certain types of therapy), prostate and colon and improvement in heart health.