To truly consume a healthy diet, the vast majority of the diet must be composed of health-promoting foods, and disease-promoting foods must be avoided. To define health-promoting and disease-promoting foods, we can turn to science to learn which foods are consistently shown to be protective against chronic disease (or associated with disease risk), which foods are associated with longevity (or mortality), and which foods contain known anti-cancer substances (and which contain cancer-promoting substances).
True health-promoting foods – these foods have the power to protect, to heal and prolong human lifespan:
Green vegetables. Many green vegetables (such as bok choy, broccoli, and kale) belong to the cruciferous family, vegetables that contain potent anti-cancer compounds called isothiocyanates (ITCs).1 Green leaves are perhaps the most powerful longevity-inducing foods of all.
Onions and mushrooms also have well-documented cancer-protective properties. Onions and their Allium family members contain chemoprotective organosulfur compounds2, and consuming mushrooms regularly has been shown to decrease risk of breast cancer by over 60%.3
Fruits, especially berries and pomegranate. Blueberries, strawberries, and blackberries are true super foods. They are full of antioxidants and have been linked to reduced risk of diabetes, cancers and cognitive decline.4 Pomegranate has multiple cardiovascular health benefits, for example reducing LDL cholesterol and blood pressure.
Beans are an excellent, nutrient-dense weight-loss food - they have a stabilizing effect on blood sugar, which promotes satiety and helps to prevent food cravings. Plus they contain substances that lower cholesterol, and regular bean consumption is associated with decreased cancer risk.5
Nuts and seeds. Nuts contain a spectrum of beneficial nutrients including healthy fats , LDL-lowering phytosterols, circulation-promoting arginine, minerals, and antioxidants. Countless studies have demonstrated the cardiovascular benefits of nuts, and including nuts in the diet has been shown to aid in weight control.6 Seeds have even a richer micronutrient profile, abundant in trace minerals, and each kind of seed is nutritionally unique. Flaxseeds provide abundant omega-3 fats, pumpkin seeds are rich in zinc and iron, and sesame seeds are high in calcium and multiple vitamin E fractions.
True disease-promoting foods – harmful foods that should be avoided:
Cheese, butter, and ice cream. These are dangerous foods that are loaded with saturated fat, that contribute to elevated cholesterol levels and several cancers.7 Dairy products are also associated with prostate cancer in men.8
Potato chips and French fries. High heat cooking produces acrylamides, dangerous cancer-promoting substances. Acrylamides have been shown to cause genetic mutations in animal studies leading to several cancers. Fried starchy foods, like potato chips and fries, are especially high in acrylamides and other toxic compounds. Baked starchy foods like breakfast cereals and crackers also contain these dangerous substances.
Refined carbohydrates. Sugar and white flour products are not nutritionally inert, simply adding a few extra calories to the diet – they are harmful. Devoid of fiber and stripped of vital nutrients, these refined foods promote diabetes, cardiovascular disease, and cancer.9
Salt. The dangers of salt are increasingly recognized, with government agencies finally considering salt reduction programs. Excess salt intake contributes not only to high blood pressure, but also to kidney disease, heart disease, osteoporosis, stroke, ulcers, and stomach cancer. Salt consumption becomes the leading contributor to a premature death in a individual eating an otherwise health-supporting diet.
Pickled, smoked, barbecued, or processed meats. Processed meats have been strongly and consistently linked to colorectal cancer, and have also been linked to prostate cancer. Processed meats contain carcinogenic substances called heterocyclic amines.10 In fact, any type of meat cooked at a high temperature will also contain these substances – for example, grilled or fried chicken was found to have the highest level of heterocyclic amines.11 High processed meat intake is also associated with increased rates of death from cardiovascular disease and cancer.12
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