Is fat bad? Are grains our nemesis? Is salt a killer? Every time we think there's a definitive, one-size-fits-all answer, the prevailing wisdom shifts. Experts proffer this advice: Use common sense. “Studies make it clear that a diet based on whole, unprocessed, and preferably organic plant foods is the ticket to long-term health,” says Steven G. Pratt, MD, co-author of SuperFoods Health Style (William Morrow, 2006). With that in mind, consider these powerful food truths for a lifetime of healthy eating.

Rethink carbs

For years, Americans looked to the grain-heavy food pyramid for nutrition guidance. Although the USDA revised the chart in 2005, we've continued to feast on refined bread, pasta, and rice to our detriment. But listen up: It's not just white carbs that do more harm than good. “Even ‘whole’ grains have a negative effect on blood-glucose levels if they're not high in fiber,” says Shari Lieberman, PhD, CNS, co-author of The Real Vitamin and Mineral Book (Avery, 2007). “If you're talking about a special high-fiber bread with 6 grams of fiber per slice, that's one thing. But most commercial wheat breads only have 1 or 2 grams of fiber a slice.” Consuming low-fiber carbs is a recipe for blood-sugar spikes, which over time can cause insulin imbalance, inflammation, cardiovascular disease, and cancer, Lieberman says.

First line of defense: Swap most grains for fruits, vegetables, and legumes. Compare the paltry fiber in a slice of whole-wheat bread to that in a cup of raspberries (8 grams) or kidney beans (a spectacular 14 grams). When you do eat grains, choose those with 4 grams of fiber or more per serving, such as brown rice or barley. Make pasta primavera with a third of the noodles (use high-fiber pasta) and double the vegetables; in burritos, use a 2 to 1 ratio of beans to brown rice. Or try slathering garlicky tomato sauce over braised chard instead of pasta. Serve spicy, fragrant lentil curry over sautéed spinach instead of rice. “There's nothing in grains that you can't get in vegetables and legumes,” says Lieberman. “Many people in my practice have given up grains altogether, and they feel a heck of a lot better.”

Embrace beans

Loaded with fiber and disease-fighting phytochemicals, “beans are one of the best vegetarian protein sources on the planet,” says Pratt. “Unlike animal proteins, they help prevent cardiovascular disease and cancer, two of the most common diseases that kill people. They also stabilize blood sugar and help reduce insulin resistance, which protects against diabetes.” It's incredibly easy (not to mention economical) to soak and cook dried beans. Also stock up on salt- and fat-free canned cannellini, garbanzo, great Northern, black, and pinto beans. Make a habit of adding them, whole or puréed, to everything: soups, salads, eggs, sandwiches, pasta sauces, gratins, stir-fries … you get the idea.

Sleuth out salt

We're saturated with salt. The American Heart Association (AHA) recommends no more than 2,300 mg of sodium daily, but the average American consumes at least three times that — putting the body at risk for high blood pressure, heart attack, stroke, and kidney disease. The results of a large international study, published in 2007, suggest that a 15 percent reduction in salt intake could save an estimated 8.5 million lives over a 10-year period.

The FDA is considering setting limits on the amount of salt added to processed foods, a shift precipitated in part by pressure from consumer groups and the AHA. Right now, an innocent-looking cup of spaghetti sauce contains a scary 1,054 mg. Fast food is another big offender. But even a “healthy” alternative, like a 6-inch submarine sandwich with lean turkey, no cheese, and extra vegetables on whole-wheat bread, contains a massive 1,651 mg of sodium.

Research shows that after eight to 12 weeks of scaling back, taste buds prefer less salt, so get started today. Avoid cured and brined meats, and rinse salty foods, including olives, feta cheese, and canned fish to remove roughly 30 percent of the sodium. Instead of reaching for the shaker, season foods liberally with herbs and spices. Garlic is a good pick; or try lemon zest, turmeric, curry or chili powder, cumin, rosemary, and sage. And compare nutrition labels — sodium amounts vary drastically, even within a category of food, such as salad dressings.

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