Despite the bad rep fasting can get, it's actually quite healthy. It helps promote bodily processes which naturally detoxify you. Here's a breakdown of what exactly fasting does for you:
Between the second you stop eating and two hours after, your body is breaking down glycogen. You should feel normal, because this isn't that long of a time period. Your blood sugar rises and your pancreas release insulin to help break glucose down for energy and for storage.
During this period, your blood sugar will fall. This is a natural effect of insulin. Because insulin is delivered directly to your circulatory system after eating, blood sugar will likely not rise again.
This is when you'll probably feel hungry. Most people eat meals this long after their previous, so your body is reminding you to eat. However, you're probably not actually hungry. Your glycogen reserves that we talked about earlier are actually being dipped into right now for energy. You're digesting the last of your consumed food and you may lose a tiny bit of body fat as your body does these things.
During this period, your body is in a process called gluconeogenesis. Big word, but all it really means is that your body has officially made the switch into fasting. This process actually increases the amount of calories you burn, and your energy is being derived from body fat, not carbohydrates.
At this point, the last bits of glycogen stored by your body are being depleted. This means that in order to function, your body is using fat for energy.
Now that fat is finally fueling your body, you are entering a state called ketosis. Your liver is converting fat into ketone bodies, and alternative source of energy. Additionally, ketosis produces fewer inflammatory by-products, so it's better for your heart, brain, and metabolism!
Your body is still using fat completely to fuel your body, but at the 18 hour mark, energy from fat increases by as much as 60%. Ketone body levels are rising, which makes your body better at metabolism regualtion.regulation. Additionally, anti-inflammatory and rejuvinative processes are heightened and ready to do their jobs.
Your body is now triggering autophagy, which literally means "self devouring"-- but don't panic! This is simply your cells cleaning up and getting rid of components which are unnecessary or dysfunctional. Viruses and bacteria are also broken down. You finally have energy for cells to rebuild and remake themselves, which is significant for their health. Your body is literally turning the clock back and making younger cells.
Your body is now more able to increase lean muscle mass. Additionally, your cardiovascular health is improving because of increased growth hormone levels(a result of increased ketone bodies).
Your body has increased sensitivity to insulin because insulin is at its lowest level since you began fasting. Increased sensitivity is good for you-- inflammation is reduced, and autophagy is more easily activated.
Your body is recycling damaged cells and enters what is essentially survival of the fittest. Your body increases the speed of regeneration of immune cells, and your cells are in a state of self-renewal. This is the final stage of benefit from fasting, so it's good to break soon after reaching this state, usually within 24 hours.
If you've just exercised, be sure to include protein. Scrambled eggs can be good for this.
Ease into it. If you binge straight out of the door, you will feel sick and likely throw up. Start small, think of your safe foods.
Break in the morning. It'll make you feel a little more fueled for the day ahead.
Eat bland food & don't eat too fast. It might help to take a probiotic beforehand too.
