When you eat a starch, your body uses it right away to fuel your fast-paced life or stores it in your muscle, liver or fat cells for energy in between meals. Starches -- carbohydrates in potatoes, grains, corn, squash, bread, pasta, baked goods and fruit -- power your brain, give you energy to exercise and keep you breathing. Watch your total caloric intake because if you eat more than you need, the extra gets stored as fat.
After you digest a starch, it's absorbed into your bloodstream and referred to as blood glucose. The glucose, or carbohydrate, in your blood gets used by cells for energy, or it gets stored as glycogen in your body for later use. Your blood sugar is usually lowest between meals or after hitting the gym. To stay healthy and active, get 45 to 65 percent of your total calories from starches, or 225 to 325 grams of carbohydrate per day for a 2,000-calorie diet.
If your body has all the carbs it needs for energy, the glucose in your blood is assembled into complex carbs called glycogen and put into storage in your muscles and liver. One gram of glycogen gets stored with 3 grams of water. This glycogen and water stay in your muscles and liver until the next time you work out or go for a jog. Glycogen in your muscles is used in the muscle cells themselves, while glycogen from your liver has to be broken down, released back into your bloodstream as glucose and then used by your flexing muscles. As you burn up the glycogen, you'll sweat out the water stored with it or lose the rest in urine.
Eating more starch than you need won't give you extra glycogen because less than one day of energy can be stored in your body as glycogen. If you binge on carbs and eat more than you burn, the excess starch is converted to fatty acids and glycerol, which are stored in your fat cells. Once you have excess carbohydrates in fat cells, the stubborn fat stays there until you exercise it off.
Using Fat Storage
To burn off the starches stored as fat, glucose in your bloodstream and glycogen in muscles and the liver has to be used up first. After depleting these stores, your body is forced to break down those fat cells for energy. To achieve this fat loss, eat fewer calories than your body needs in a day and rev up your activity and exercise levels.
- ExRx.net: Glycogen
- ACSMs Primary Care Sports Medicine; Douglas B. McKeag & James L. Moeller
- Human Physiology From Cells to Systems; Lauralee Sherwood
Erica Kannall is a registered dietitian and certified health/fitness specialist with the American College of Sports Medicine. She has worked in clinical nutrition, community health, fitness, health coaching, counseling and food service. She holds a Bachelor of Science in clinical dietetics and nutrition from the University of Pittsburgh.