However, this will range from around 1000 kcal daily for an infant to as much as 3200 kcal daily for a young male of 16-18 years who leads an active lifestyle. The minimum recommended calorie intake is 1800 for both sexes.
A 1,200-calorie diet is much too low for most people and can result in negative side effects like dizziness, extreme hunger, nausea, micronutrient deficiencies, fatigue, headaches, and gallstones ( 23 ). Furthermore, a 1,200-calorie diet can set you up for failure if long-term weight loss is your goal.
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 very low calorie diet is a clinically supervised diet plan that involves eating about 800 calories a day or fewer. They are sometimes considered for obese and severely obese people who are managing diabetes, going to have surgery or preparing for fertility treatment.
As a general rule, people need a minimum of 1,200 calories daily to stay healthy. People who have a strenuous fitness routine or perform many daily activities need more calories. If you have reduced your calorie intake below 1,200 calories a day, you could be hurting your body in addition to your weight-loss plans.
People may turn to 1,000 calorie diets when they are desperate to lose weight quickly, such as before a vacation. While adults could follow this type of diet relatively safely for a couple of weeks, it is not something that doctors advise for extended periods.
Other models have said they eaten anywhere from 800 to 3,000 calories per day. In essence, a model's diet totally varies depending on their body type, how easily they gain or lose weight, and what their nutritionist is asking of them.
Short-term risks of eating 1,000 calories a day may include dizziness, hunger, gallstones, nausea, fatigue, headaches, and nutrient deficiencies. It can lead to nutrient deficiencies, slow metabolism, and make bones weaker if you exercise along with a low-calorie diet.
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.
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.
Short-term fasts boost metabolism by up to 14%
It's well established that very long periods without food can cause a drop in metabolism ( 28 , 29 ). However, some older studies have shown that fasting for short periods can actually increase your metabolism, not slow it down ( 30 , 31 ).
As for most people, this number of calories is too little to obtain enough nutrients, and you should not follow the 1000 calorie meal plan for more than a week. Dieters should avoid highly vigorous physical activity during the dieting period.
You can't lose weight on 1200 calories a day because you're no longer in a calorie deficit. Your body has adapted to what it's been doing and plateaued. If you start your diet with a 500 calorie deficit per day, your body adapts to this in various way so that over time your energy requirements are reduced.
Most adults need a minimum of 2000 calories to sustain metabolism, muscle activity, and brain function. However, too many calories can lead to weight gain and a variety of diseases.
Some versions of the diet also restrict calorie intake to as few as 1,300 calories per day, which is insufficient for most people. This could cause a range of side effects, including hunger, fatigue, nausea, and constipation ( 14 ).
The Victoria's Secret models try to stick to 5 smaller meals per day, eating every 3 hours. They also eat the majority of their carbs earlier in the day, rather than at night. This is because your body can metabolize carbs better in the morning (and post-workout) and is less likely to store carbs as fat at these times.
In other words, if you stick to the calorie intake recommended by WLR, you can be sure your body won't go into starvation mode. As a general rule though, most nutrition experts recommend never going below 1,000-1,200 calories a day if you're dieting on your own.
In humans. Ordinarily, the body responds to reduced energy intake by burning fat reserves and consuming muscle and other tissues. Specifically, the body burns fat after first exhausting the contents of the digestive tract along with glycogen reserves stored in liver cells and after significant protein loss.
Scientists have known for a while that when a body becomes starved for sustenance, cells start eating bits and pieces of themselves. It's a process known as “autophagy” and one that's a normal part of the cell life cycle; it's how other cells get energy during the tough times.
The 800-calorie rapid weight loss phase is safe for most individuals for up to 12 weeks, as long as you stick to our recommendations, drink plenty of water and use a multivitamin.
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.
Regularly eating fewer calories than your body requires can cause fatigue and make it more challenging for you to meet your daily nutrient needs. For instance, calorie-restricted diets may not provide sufficient amounts of iron, folate or vitamin B12. This can lead to anemia and extreme fatigue (16, 17, 18).