You likely feel bigger after fasting primarily because your body is replenishing its glycogen stores, which retain water.
When you fast, your body depletes its glycogen stores (stored glucose) in the liver and muscles. Once you break the fast and start eating again, your body prioritizes restocking these glycogen reserves. Since glycogen attracts and holds water, this process leads to water retention, making you feel "bigger."
Here’s a breakdown:
- Glycogen Depletion During Fasting: During fasting, your body uses stored glycogen for energy. This process reduces both glycogen and water levels.
- Glycogen Replenishment After Fasting: When you start eating after a fast, your body actively replenishes glycogen stores in the liver and muscles.
- Water Retention: Each gram of glycogen stored is accompanied by several grams of water. This water retention contributes to the feeling of being "bigger" or bloated. As the reference states, when you break a fast, "your body restocks your liver and muscles with glycogen. Since glycogen is mostly water weight, that can easily add a few quick pounds of water."
- Temporary Weight Gain: The increased water weight is normal and usually temporary.
Essentially, it’s not fat gain; it's water retention due to glycogen replenishment.
Minimizing Water Weight Rebound
The reference suggests, "there's at least one trick to minimize it." Here's how you might minimize the water weight rebound:
- Break Your Fast Strategically: Start with easily digestible, lower-carbohydrate foods to avoid a rapid spike in glycogen storage.
