In general, if you cut about 500 calories a day from your usual diet, you may lose about ½ to 1 pound a week. But this can vary depending on your body, how much weight you want to lose, your gender and activity level.
Danger of deficiencies
The greatest dangers associated with a 500-calorie diet relate to vitamin and mineral deficiencies. Vitamin and mineral deficiencies can lead to many health problems. In fact, most people cannot meet their vitamin and mineral requirements if they eat less than 1200 calories per day.
A calorie deficit of 500 calories per day is effective for healthy and sustainable weight loss. Eliminating sugary beverages, consuming mostly minimally processed foods like fruits and vegetables, and eating home-cooked meals can help you reach a calorie deficit without calorie counting.
On average, a person will burn at least 1800 calories a day without exercise. To lose weight, you must be in a calorie deficit. Caffeine supplements can help you achieve this state by boosting your BMR to promote fat burning.
However, sometimes water retention can be caused by other aspects that can be the reason behind calorie deficit but not losing weight. Salty food, high carbohydrate intake, lack of exercise and some medications can cause water weight gain even on a caloric deficit (10).
However, calorie intake should not fall below 1,200 a day in women or 1,500 a day in men, except under the supervision of a health professional. Eating too few calories can endanger your health by depriving you of needed nutrients.
You need to carefully plan your menu when eating the bare minimum. While it's safe for both men and women to limit their intake to 1,200 calories a day, women may have an easier time meeting their nutrient needs than men, says Harvard Health Publications.
If you can eat 500 fewer calories every day, you should lose about a pound (450 g) a week. Always talk with your health care provider to determine a healthy weight for you before starting a weight-loss diet.
Example: If you exercise more to burn an extra 500 calories each day, you'll lose about one pound of fat in a week (500 calories x 7 days = 3,500 calories).
Traditionally, weight loss plans have been based on the assumption that you need to achieve a calorie deficit 3,500 calories per week (or 500 calories per day) to lose one pound per week.
Cecil Adams, the erstwhile columnist, claims to have run the numbers with his assistant and found that a whole lot of potatoes and milk would get you most of what you need – with the exception of the mineral molybdenum. But you can get all you need of that by also eating a bit of oatmeal.
Eating fewer calories may slow down aging and increase longevity. Eating less may lengthen your life. Researchers have increased life-spans in yeast and mice by having them consume fewer calories per day, and ongoing studies suggest that a strict low-calorie diet may slow aging in primates, too.
Eating too few calories can be the start of a vicious cycle that causes diet distress. When you cut your calories so low that your metabolism slows and you stop losing weight, you probably will become frustrated that your efforts are not paying off. This can lead you to overeat and ultimately gain weight.
For most people, there are no serious dangers involved in eating one meal a day, other than the discomforts of feeling hungry. That said, there are some risks for people with cardiovascular disease or diabetes. Eating one meal a day can increase your blood pressure and cholesterol.
It is commonly said that if you eat too few calories, your metabolism will slow down to a point where you no longer lose weight. Part of this is true: as you lose weight your energy expenditure does drop. However, consuming too few calories cannot and will not cause you to gain weight. This is simply impossible.
Factors that may increase a person's metabolic rate include consuming an appropriate number of calories, favoring protein over carbohydrates and fat, getting enough sleep, and some types of exercise, such as resistance training.
A person can create a calorie deficit by not consuming as many calories as they need to maintain their body weight during the course of a day or week. Over time, this calorie reduction can lead to weight loss.
The diet doesn't have enough calories
Eating too little — say, 1,000 calories a day — can prevent you from losing weight, too. "When you don't eat enough, your body is starving and it's not going to lose any extra weight" because it needs those energy stores to keep you alive, Fakhoury said.
Put simply, to lose 1 lb of body fat per week, people will need to have a deficit of around 500 calories per day. They can achieve this by consuming roughly 500 calories fewer than they are currently, by burning an extra 500 calories per day with exercise, or a combination of the two.