Is All Fiber Created Equal?

Fiber, fiber, fiber. It's the theme of 2013 and for a good reason. Besides keeping our bodies, well, regular, a diet high in fiber is a great weight loss tool, lowers cholesterol, and reduces the risk of developing heart disease and diabetes. It keeps us feeling full, and when you're full, you eat less between meals. Easy enough, right?

Not so fast. All fiber is not created equal, and if you aren't careful, putting too much of the wrong kinds of fiber in your body can leave you with an upset tummy. Not to worry; I've created a complete guide of the best fiber-rich foods and those with a red flag to steer clear of.

[See 10 Fiber-Friendly Food Swaps to Help You Lose Weight]

First, let's take a look at the two kinds of fiber: soluble and insoluble. The basic rule of thumb is that soluble fiber dissolves in water and insoluble fiber does not. Soluble fiber, found in oatmeal, lentils, oranges, pears, strawberries, nuts, beans, and blueberries, helps lower cholesterol. Foods containing soluble fiber are attracted to water, so it's best to drink lots of water in order to reap nutritional benefits. Soluble fiber also delays digestion, giving you a fuller feeling.

Insoluble fiber, found in whole wheat, whole grains, wheat bran, seeds, nuts, barley, and dark leafy vegetables, speeds up the digestion process and helps control IBS symptoms. This kind of fiber is not absorbed by water and passes through your body quickly. Both types of fiber are crucial for a healthy diet.

[See IBS? Could be the FODMAPs]

When you introduce more fiber in your diet, do so in small portions and increase your water intake to avoid a stomachache.

Here are my favorite picks and skips:

-- Cereal: Nature's Path Organic Smart Bran cereal vs. Fiber One Caramel Delight

Fiber One Caramel Delight cereal boasts 35 percent of your daily recommended fiber, but when you really read the nutrition label, you realize it's just too good to be true. Yes, it's packed with fiber, but much of this fiber comes from artificial sources. The artificial stuff can leave you with an upset stomach--not exactly the best way to start your day.

For all the cereal lovers out there, I have an option for you. I recommend my clients start their day with Nature's Path Organic Smart Bran cereal, which packs in 13 grams of fiber per serving--that's a whopping 52 percent of your daily recommended value! Not to mention you can pronounce every ingredient on the label, a sure sign you're putting the right foods in your body.

[See When Nutrition Labels Lie]

-- Nutrition Bars: Gnu Foods vs. Fiber One

When it comes to nutrition bars, my whole family can't get enough of Gnu Bars. I say Gnu Bars are fiber at its finest, giving your body nearly half of the daily value of fiber it needs to stay healthy. I always stress to my clients the importance of unprocessed foods, and these bars are made with the entire grain. It's about as unprocessed as is gets. Plus, this bar is rich in beneficial nutrients, minerals, and antioxidants.

[See Empower Your Diet With Antioxidants]

On the contrary, Fiber One bars are on my skip list. They are made with artificial sweeteners to improve taste, leaving out essential vitamins, minerals, and antioxidants. Instead of helping with weight loss, added sugars contribute to weight gain.

-- Bread: La Tortilla Factory Low-Carb, High-Fiber Tortillas vs. Sara Lee's "45 calories & delightful" whole-wheat bread

Lunch is the perfect time to give your diet a boost of fiber. It's all about the outer layer holding the fixings together, and La Tortilla has the lowest-calorie, highest-fiber wrap I've ever seen on the market. I was even scratching my head when I saw one tortilla contains 7 grams of fiber for just 50 calories.

But don't assume that light in calories means high in fiber. One slice of Sara Lee's "45 Calories & Delightful" whole-wheat bread contains 45 calories, but not enough fiber (only 2.5 grams) to keep you full.

[See Going Gluten-Free? Don't Forget Fiber.]

-- Crackers: FiberRich vs. Wheat Thins Fiber Selects

Snack time! When you hit that midday slump and your stomach starts growling, fibrous crackers can hold you over until dinner. My pick: FiberRich crackers. The no-no: Wheat Thins Fiber Selects.

There's a good reason why it's so easy to finish a whole box of Wheat Thins in one sitting. Although they may taste good and give your body 5 grams of fiber, you can really get a better fiber boost from other crackers.

Rule of thumb: All-natural foods are better for overall health in the long run. My kids look forward to snacking on FiberRich crackers, which give you 5 grams of fiber per serving. Plus, if your mind is set on losing weight this year, healthy, smart snacking is the key to success.

[See Swap This for That: Tips for Feeding Healthy Kids]

Hungry for more? Write to eatandrun@usnews.com with your questions, concerns, and feedback.

Heather Bauer, RD, CDN, is a nationally-recognized nutrition expert, author, and entrepreneur. She is the author of two top selling books, The Wall Street Diet and Bread is the Devil. She is the founder of Nu-Train, a nutrition consulting company, and Bestowed, a subscription service that offers consumers a personalized way to discover, sample, shop, and learn about the best nutrition and lifestyle products on the market.