If you're still holding on to your New Years resolution to eat better and exercise more, good for you. But, if you're still struggling to get in shape and lose weight, understanding how calories play a part in overall health may help you reach your goal more easily.

Understanding the basics of how calories work is great. But, as you see, counting calories (or Calories depending on context) is complicated and every person's needs are different.

Before you give up on that resolution to lose weight and get healthier, or before you start, spend some time with your doctor and a dietician. Both have the knowledge to define exactly what you need, including calories, to achieve your goal and get healthy this year.