Sugar overload is another red flag. According to the USDA, the average American eats about 30 teaspoons of sweeteners per day — that's nearly four times the daily recommended limit of 8 teaspoons, which is roughly the amount in just one can of soda. Sugar, like refined grains, causes insulin spikes, which prompts inflammation and all its associated ills. That goes for honey, maple syrup, and unrefined cane sweeteners, too. And even if you eschew candy and soda, check your pantry. Sugar (in many guises) lurks in soup, bread, crackers, canned vegetables, salsa, peanut butter, pasta sauce, and more.

As with sodium, the goal is to retrain your palate. Most recipes taste absolutely fine with one-fourth to one-half less sugar; kick up flavor with sweet spices like cinnamon, ginger, and cloves. Stock up on berries, apples, and other low-glycemic natural treats. And use low-glycemic agave nectar or xylitol instead of sugar; or try stevia, a natural sweetener that doesn't impact blood sugar.