Can someone explain the science to me?????

I'm on my 3rd week too, and I am in the same boat! I was doing FINE at first, but now I feel like I'm starving too.

You need to eat back your excercise calories.

it takes about two or three weeks for your body to adjust to your new diet. after it has adjusted and you have burned through most of you energy stores your body will start burnign more fat which increases your metabolism. An increased metabolism will mean you are burning more calories, but will also mean you get hungrier. too deal with this i started eating a mid morning and mid afternoon snack ( haven't looked at your diary to see what your eating). the inbetween snacks i choose are usually containing protein as proteins help you feel full. also keep a big jar of pickels around and eat a pickel if you get soo hungry you can't take it. a pickel will help combat low blood sugar / insulin based hungry pangs due to the acids in the pickel and they have very little calories, especially when considering the size of them.

forgot- also i shifted most of my highest calorie meal to breakfast.

The past few days you haven't been eating enough. Definitely try to add a little more protein and fiber during snack times to combat the hunger pangs. You might also try eating a bigger breakfast with some cereal and/or fruit or adding something a little more filling an hour or two after you eat your yogurt. I know when I used to eat just a yogurt for breakfast that I always felt hungry again a little while later.

Try upping your fiber and protein throughout the day. As your metabolism increases, so does the need for more fuel. So, it's natural that your body is hungrier. There's nothing wrong with increasing your intake and creating the net deficit through exercise.

some of the experts say to eat every few hours. I know Jillian Michaels is big on this as well as Bob from the Biggest Loser. You want to keep your engine running all day long.

On a typical workday I eat a variation of this:

- Oatmeal and coffee at 8:30
- piece of fruit at 11
- a frozen burrito or other organic meal. Often it's vegetarian (or if it involved meat it's humanely raised which has lower fat and cholesterol). So this lunch for me always involves protein and veggies.
-another piece of fruit (or a cup of berries) around 2
- low fat or no fat yogurt around 3 or 4pm
- If I dd not eat a piece of fruit after lunch, I'll have one before the gym
-Dinner with my husband, typically a meat, veg, and grain or potato.
-sometimes I have wine or beer with dinner
-Bed at 11pm

Try to eat more protein for breakfast and throughout the day. I eat plain Greek yogurt and a glass of skim milk for breakfast, and that protein helps keep the "I'm starving!" feeling from rolling in 2 hours after eating. I'd also suggest eating more for breakfast...somewhere in the 300-350 range.