If you don't eat for 1 day you can lost 1/2 a lb of weight to 1.5 lbs to 3 lbs of weight depending on your current weight.
However much of the weight lost if you don't eat for 1 day is water weight and is a result of your body using up stored glycogen and releasing associated water.
And after you drink more water and rehydrate you will likely gain this water weight back.
You'll need to cut your calorie intake per day to lose weight but you should still eat at least once a day to remain healthy.
Losing weight in a healthy way can take a few months to a year or longer when done correctly.
If you eat only 500 calories a day you can lose some weight but if you're not careful with a 500 calorie diet it can be dangerous and lead to gallstones, metabolic changes, muscle loss, severe nutritional deficiencies and other serious side effects.
When eating only 500 calories a day it's very difficult for your body to get all of the required vitamins and minerals that the body needs which can lead to malnutrition.
Common nutritional deficiencies that can occur when eating only 500 calories a day are vitamin D deficiency, vitamin C deficiencies, zinc deficiencies, iron deficiencies, calcium deficiencies and vitamin B12 deficiencies.
Your body will also start breaking down the muscle tissue for energy when calorie intake is extremely low and can be detrimental to overall health and metabolism.
And prolonged and severe restrictions of calories can slow down your body's metabolism and make weight loss more challenging in the long run.
And rapid weight loss from not getting enough calories can lead to VLCDs which increase the risk of gallstones.
Other side effects of eating only 500 calories a day or not enough calories a day include diarrhea, nausea, fatigue, constipation, hair loss, menstrual irregularities and weakened immune system function.
You can eat 500 calories a day without being hungry by eating high fiber foods such as whole grains, vegetables and fruits.
Fruits, vegetables and whole grain foods that are high in fiber promote satiety and help keep you feeling full longer so you can eat less calories but not feel hungry.
When eating snacks you should eat high fiber snacks instead of calorie dense snacks like a cup of some air popped popcorn, a cup of grapes with a low fat cheese stick or a small apple with 12 almonds.
The cup of popped popcorn will be at most 30 calories.
Also add vegetables to salads, pastas or even stews and include fruits as part of your snacks and meals.
And opt for eating whole grains such as whole wheat bread, quinoa and brown rice instead of refined grains.
You should also eat high volume and low calorie foods such as eating a large salad with leafy greens, small amount of lean protein and vegetables.
Soups are also naturally low in calories and can be very filling and keep you feeling full and even eating non starchy vegetables like roasted vegetables, steamed vegetables or even sauteed vegetables.
Also include protein in your meals as protein also helps you feel full longer.
Some examples of lean protein are lentils, beans, fish and lean chicken and if you're trying to eat less calories you should avoid high fat sources such as fatty meats or full fat dairy food products.
Also stay hydrated and drink plenty of water as the water can help you feel full and help regulate your hunger cues.
And avoid sugary drinks that are high in calories and empty of nutrients.
Pre planning your meals and snacks can also help you eat less calories and feel full and not hungry as pre planning your meals helps you avoid impulse eating and ensures that you have healthy food options readily available.
And be sure to eat at regular intervals as skipping meals can make you feel hungrier later.
Also pay attention to your body's hunger cues and eat when you're genuinely hungry and allow yourself some occasional treats to eat.