Don’t look for nutrients in diet soda; get it from whole foods—especially high-fiber, filling ones—instead.

"Keen! Only four more bottles and I'll have a full day's dose of that neat-o B12!"

RODALE NEWS, EMMAUS, PA—The Food and Drug Administration (FDA) sent a letter to president and CEO of The Coca-Cola Company this month, warning him that the company’s claims about the vitamin and mineral content of Diet Coke Plus are unlawful and misleading.

THE DETAILS: FDA sent the letter to Coke head honcho Muhtar Kent because carbonated beverages and other junk-food items aren’t supposed to be fortified, or labeled to make it appear they’re more nutritious than competitors. Coke was ordered to send FDA a plan for fixing the faulty labeling within 15 days. "We take seriously the issues raised by the FDA in its letter," Dan Schafer, Coca-Cola North America spokesman, wrote in a statement. "This does not involve any health or safety issues, and we believe the label on Diet Coke Plus complies with FDA’s policies and regulations. We will provide a detailed response to the FDA in early January."

WHAT IT MEANS: If you’re looking for vitamins and minerals, please don’t turn to a glass of soda. You’d have to drink nearly five 12-ounce cans of Diet Coke Plus to get your recommended daily allowance of vitamins B3 (niacin), B6, and B12. Not only that, certain vitamins break down over time in acidic conditions (like, for example, those inside a bottle of soda), especially if left unrefrigerated. So while carbonated soft drinks boasting additives such as ginseng and B vitamins are showing up in stores everywhere, don't be fooled into thinking they're nutritious.

Instead of relying on diet soda as a calorie-controlling, nutrient-providing panacea, try these strategies:

• Find your fiber fix. Shoot for 25 grams of fiber a day, and try to get it from whole foods. It’ll make you feel full so you won’t want to keep reaching for fiber-deficient, nutrition-lacking soda or chips.

• Sneak in fiber gradually. Add a little salad to your dinner, trade in white rice for brown, plop a few kidney beans or chickpeas into soup, or switch to cereal with at least 5 grams of fiber per serving. If you can’t commit to that, mix ½ cup of a fiber-filled cereal with ½ cup of your favorite. Build your fiber intake up to 25 grams slowly so you don’t feel bloated from a sudden change.

• Get B in better ways. You can find B12 in meat, egg, and dairy products, and it’s fortified in some soy milks, veggie burger mixes, and cereals. Hazelnuts, bananas, bran, and peanuts pack vitamin B6, while mushrooms, sesame seeds, and peanuts are sources of B3.