By Melissa F. Pheterson

As we recoup from the holiday binge and struggle to stick to our resolutions, getting the facts on food trends is key to our sanity — and shape. Dr. Madelyn Fernstrom, diet and nutrition editor on NBC's Today, helps us "ring in the new" by sizing up the latest in diet research from the scientific world. Here's the skinny on fact vs. fiction when it comes to your optimal health and weight in 2008.

We all know to shoot for the recommended daily allowance (RDA) of nutrients — popping supplements to meet our quota lest we fall short. Consumer spending on vitamins has doubled in the past 6 years and fortified foods and vitamins are in. But "when it comes to vitamins, more isn't always better," says Madelyn. The hazards of OD-ing are especially acute for fat-soluble vitamins — including vitamins D, E and A and beta-carotene, which don't easily pass from the body. Tread carefully with supplements and know the "ceiling" of safe intake.

Ask your doctor these questions about potential interactions >>

Learn what supplements you should be taking >>

Avoid vitamins labeled as "mega," "thera" or "super" >>

We call them pats on the back, but life's little rewards often aim for the stomach: think Friday happy hours, pizza parties, birthday cakes. A Florida school district has recently partnered with McDonalds to redeem good report cards with Happy Meals. If you constantly dish out rewards from a bowl, you may crimp your weight-loss efforts and instill bad habits in your kids — or worse, says Madelyn, push them toward obesity. Incentives don't have to revolve around eating. But food-as-reward does have its place — in moderation.

Do a fun activity to celebrate a job well done. Share it here >>

Order these "better-for-you" choices on a fast-food menu >>

Try these tips to use food rewards sparingly, so they do feel special >>

For many dieters, working out is top priority — especially after New Year's. But is exercise foiling your weight-loss regimen by making you ravenous?

A new book by Dr. Gary Taubes called Good Calories, Bad Calories claims that exercising drives you to devour more. That's not always true, says Madelyn. Biologically, extreme exercise does stimulate appetite. And while it's true that most people over-estimate their exertion and lowball their food intake — a recipe for more liberal eating — all it takes is mindful monitoring to correct the imbalance. "It's a matter of balancing exercise with intake of food, and factoring in the time and intensity of your workouts," Madelyn says.

Advice on balancing calories in and calories out >>

Learn how many calories you burn during your workouts >>

Discover the best calorie plan to maximize your weight loss >>


NEXT: Are the Bugs in Your Gut Making You Fat? >>]]> http://i.ivillage.com/DF/Slideshows/snack_lovers/Breakfast/breakfast_lover_325.jpg http://diet.ivillage.com/slideshow/diet_fitness/diet_at_the_village_january/gutlevel_reaction.html

We nourish trillions of bacteria, fungi and other microbes in our small and large intestines. To thank us for feeding them, they break down food and police against invaders, but do they also play a role in weight management?

New research shows that when the munching microbes ferment food for their own energy, they "share" the bounty with their hosts — that's us — at different rates. Some hog it mostly for themselves, combusting the calories; others release the calories back to us, pumping 'em into our system. That means the same amount of food may deliver more calories to you than to your best friend. "This research is very preliminary, but hugely interesting,"says Madelyn.

Eat yogurt to lose weight and reduce tummy troubles >>

Find out if you have enough bacteria in your diet >>

Add these great sources of probiotics to your next meal >>

Start strong this year by integrating our dish on diet into your game plan:

Check out Workouts A-Z to find the best exercise for you >>

Sign up for our 6-week challenge for daily weight-loss tips >>

Confess your diet slip-up >>]]>