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Calorie intake for fast weight loss: Diet for rapid weight loss: MedlinePlus Medical Encyclopedia

Diet for rapid weight loss: MedlinePlus Medical Encyclopedia

Rapid weight loss diet is a type of diet in which you lose more than 2 pounds (1 kilogram, kg) a week over several weeks. To lose weight this quickly you eat very few calories.

These diets are most often chosen by people with obesity who want to lose weight quickly. These diets are less commonly recommended by health care providers. People on these diets should be followed closely by a provider. Rapid weight loss may not be safe for some people to do on their own.

These diets are only to be used for a short time and are usually not recommended for more than several weeks. The types of rapid weight loss diets are described below.

People who lose weight very quickly are much more likely to regain the weight over time than people who lose weight slowly through less drastic diet changes and physical activity. The weight loss is a bigger stress for the body, and the hormonal response to the weight loss is much stronger. The hormonal response is one of the reasons that weight loss slows down over time and also why weight gain occurs when the diet is stopped or relaxed.

On a VLCD, you may have as few as 800 calories a day and may lose up to 3 to 5 pounds (1.5 to 2 kg) week. Most VLCDs use meal replacements, such as formulas, soups, shakes, and bars instead of regular meals. This helps ensure that you get all of the nutrients you need each day.

A VLCD is only recommended for adults who have obesity and need to lose weight for health reasons. These diets are often used before weight-loss surgery. You should only use a VLCD with the help of your provider. Most experts do not recommend using a VLCD for more than 12 weeks.

These diets usually allow about 1,000 to 1,200 calories a day for women and 1,200 to 1,600 calories a day for men. An LCD is a better choice than a VLCD for most people who want to lose weight quickly. But you should still be supervised by a provider. You will not lose weight as fast with an LCD, but you can lose just as much weight with a VLCD.

An LCD may use a mix of meal replacements and regular food. This makes it easier to follow than a VLCD.

This diet strategy is becoming more popular. It is often compared to fasting, but the two strategies are slightly different. Time-restricted eating limits the number of hours per day that you can eat. A popular strategy is the 16:8. For this diet, you have to eat all of your meals during an 8 hour period, for example, 10 am to 6 pm. The rest of the time you cannot eat anything. There are some studies that this method can cause rapid weight loss, but there is little information so far about whether the weight loss is sustained.

Fasting is an ancient form of caloric restriction. It has become more popular recently. This is partly because some animal and human studies have shown benefits to fasting for people with diabetes and obesity. There are many different fasting regimens and it is unclear which may be the best. One of the most popular is the 5:2 system. This involves 2 days a week of fasting or VLCD and 5 days a week of eating your normal diet. Diets that incorporate fasting can cause rapid weight loss.

Some fad diets also severely limit calories to achieve rapid weight loss. In some cases, these diets are not safe. In most cases, these diets are not sustainable for long enough to cause long-term weight loss. Once you stop the diet, you are at risk for regaining the weight if you return to your old eating habits. For most people, it is safest to choose a diet in which you lose a 1/2 pound to 1 pound (225 grams to 500 grams) a week.

Rapid weight loss is more about cutting calories than exercising. Talk with your provider about what type of exercise you should do while you are on this type of diet. Your provider may suggest waiting until you are on a more long-term diet to start exercising.

Rapid weight loss diet is usually for people who have health problems because of obesity. For these people, losing a lot of weight quickly can help improve:

  • Diabetes
  • High cholesterol
  • High blood pressure

You should only follow one of these diets with the help of your provider. Losing more than 1 or 2 pounds (0.5 to 1 kg) a week is not safe for most people. It can cause you to lose muscle, water, and bone density. Rapid weight loss can also cause some side effects including:

  • Gallstones
  • Gout
  • Fatigue
  • Constipation
  • Diarrhea
  • Nausea

People who lose weight quickly are also more likely to gain back the weight quickly. This can lead to other health problems.

In general, a rapid weight loss diet is not safe for children. It may also not be safe for teens, pregnant women or older adults unless a provider recommends it.

If you have a health condition, it is a good idea to talk with your provider before starting this or any diet plan to lose weight.

Very low-calorie diet; VLCD; Low-calorie diet; LCD; Very low energy diet; Weight loss – rapid weight loss; Overweight – rapid weight loss; Obesity – rapid weight loss; Diet – rapid weight loss; Intermittent fasting – rapid weight loss; Time-restricted eating – rapid weight loss

  • Yo-yo dieting
  • Weight loss

Academy of Nutrition and Dietetics website. 4 ways low-calorie diets can sabotage your health. www.eatright.org/health/wellness/weight-and-body-positivity/4-ways-low-calorie-diets-can-sabotage-your-health. Updated January 24, 2022. Accessed January 11, 2023.

Academy of Nutrition and Dietetics website. Staying away from fad diets. www.eatright.org/health/wellness/diet-trends/staying-away-from-fad-diets. Updated April 13, 2021. Accessed January 11, 2023.

Flier EM. Obesity. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 40.

Parretti HM, Jebb SA, Johns DJ, Lewis AL, Christian-Brown AM, Aveyard P. Clinical effectiveness of very-low-energy diets in the management of weight loss: a systematic review and meta-analysis of randomized controlled trials. Obes Rev. 2016;17(3):225-234. PMID: 26775902 pubmed.ncbi.nlm.nih.gov/26775902/.

Updated by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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Does It Work for Weight Loss?

Some people follow 1,200-calorie diet plans to promote fat loss and reach their goal weight as quickly as possible.

While it’s true that cutting calories is an effective way to lose weight, research shows that reducing calorie intake too drastically isn’t good for long-term health or weight loss.

This article reviews 1,200-calorie diets and covers the potential benefits and downsides associated with low calorie dietary patterns.

A 1,200-calorie diet is a way of eating that limits the number of daily calories that you consume to 1,200. This diet is considered a low calorie diet because it provides significantly fewer calories than most average adults need to maintain their weight.

Many healthcare providers, including doctors and dietitians, prescribe low calorie diets as a go-to strategy for weight loss.

A common recommendation to spark weight loss is to decrease calorie intake by 500–750 calories per day. This usually translates to a low calorie diet of 1,200–1,500 calories per day for adult women and 1,500–1,800 calories per day for adult men (1).

Note that 1,200 calories is at the low end of the recommended low calorie diet ranges for women.

Some researchers categorize low calorie diets as dietary patterns that deliver between 800–1,200 calories per day, while very low calorie diets are categorized as diets that deliver fewer than 800 calories per day (2, 3).

These diets are typically followed for short periods of weeks to months to promote rapid weight loss.

Low calorie and very low calorie diets are commonly used in clinical settings under medical supervision, such as weight loss centers, but they’re popular with the general public as well.

In fact, many weight loss coaches, personal trainers, and popular dieting websites offer 1,200-calorie meal plans, promising that following a 1,200-calorie diet will help you “slim down fast.

These diets typically promote the use of “low calorie,” “fat-free,” and “reduced-fat” foods to help keep calorie intake low and usually involve calorie counting so that dieters make sure they’re staying under their daily limit.

While a 1,200-calorie diet may be appropriate in the short term in certain situations, 1,200 calories are far too few for the majority of adults.

Plus, while you may initially experience fast weight loss when dramatically reducing your calorie intake, studies show that low calorie diets rarely work for keeping weight off for good (4, 5).


A 1,200-calorie diet is considered a low calorie diet. Low calorie diets are used to promote fast weight loss and sometimes prescribed by healthcare professionals.

Creating a calorie deficit is necessary for weight loss. Cutting calories by 500–750 calories per day, as some health professionals advise, is likely to encourage weight loss, at least in the short term.

Many studies have shown that following low calorie diets, including 1,200-calorie diets, can promote weight loss.

For example, a study in 2,093 people with obesity demonstrated that a medically supervised 1,200-calorie meal replacement diet resulted in an average fat loss of 4.7% over 12 months (6).

In another study, adults followed a commercial weight loss program that provided either 500, 1,200–1,500, or 1,500–1800 calories per day.

After 1 year, those on the 1,200–1,500-calorie-per-day diet experienced an average weight loss of 15 pounds (6.8 kg). However, 23% of the 4,588 people following the 1,200-calorie diet dropped out of the study (7).

Studies have found that while initial weight loss using low calorie diets like 1,200-calorie diets is typically rapid and substantial, it’s often followed by greater weight regain, compared with diets using only moderate calorie restriction.

In the commercial weight loss study mentioned above, the researchers observed that rapid weight loss during the first 3 months was associated with greater regain during the 9-month weight loss maintenance phase in all three of the diet groups (7).

Another study in 57 people with overweight or obesity noted that after following a very low 500-calorie diet or low 1,250-calorie diet for 5 and 12 weeks, respectively, study participants regained 50% of the weight they lost over 10 months, on average (8).

This is because low calorie diets induce metabolic changes that conserve energy and prevent weight loss, including increased appetite, loss of lean body mass, and reductions in the number of calories burned, all of which make long-term weight maintenance difficult (9, 10, 11).

This has led many health experts to recommend eating patterns that use only small reductions in calorie intake to promote weight loss while minimizing the negative metabolic adaptations that are associated with low calorie diets (12).


Although following a low calorie 1,200-calorie diet is likely to result in weight loss, the chances of keeping the weight off are slim.

Following a 1,200-calorie diet may provide some health benefits, but it’s important to note that these benefits are associated with calorie restriction, in general, and not specific to 1,200-calorie meal plans.

Regularly consuming more calories than your body needs can lead to many health consequences, including weight gain, increased heart disease risk factors, and diabetes (13).

Fueling your body with the right number of calories is essential for the preservation of good overall health.

Many studies have shown that calorie reduction, in general, can benefit health by promoting weight loss, reducing heart disease risk factors like LDL (bad) cholesterol, and decreasing blood sugar levels and inflammation (14, 15, 16, 17, 18, 19).

There’s no question that losing excess body weight has positive effects on health and that staying within your individual calorie needs is best for your body.

However, the methods used to promote weight loss matter, and using very low calorie, restrictive dieting methods is strongly associated with increased chances of weight regain over time.

Therefore, while losing excess body weight can benefit your overall health, it’s important to choose healthy, sustainable weight loss methods over more extreme dietary patterns.

It should be noted that some research has shown that people with obesity or morbid obesity who follow low calorie or very low calorie diets under medical supervision lose weight and improve their blood sugar and lipid profiles, which can improve overall health (20).

Still, these diets are typically followed for short periods and usually associated with high dropout rates due to their restrictive nature.

Nonetheless, if you’re interested in following a low calorie diet for weight loss, it’s important to speak with a qualified healthcare provider for advice.


Losing excess body weight and fueling your body with the right number of calories is important for overall health. Although 1,200-calorie diets are associated with some health benefits, these benefits are related to calorie reduction in general.

Calorie needs are highly individualized and depend on many factors, including body size, age, and activity levels. A 1,200-calorie diet is inappropriate for most adults, including smaller women.

Though calorie requirements vary from person to person and accurate needs can only be determined using specific equipment or calculations, the average adult woman needs around 2,000 calories per day to maintain her weight, while a man needs around 2,500 (21, 22).

Again, these numbers are only averages and don’t reflect the differences in calorie needs due to factors like age, activity levels, and height. However, these average calorie need estimations gives you an idea of how low 1,200 calories is.

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.

Restricting calories leads to metabolic changes in your body. These include increases in hormones like ghrelin and cortisol, which drive hunger, as well as a drop in resting metabolic rate (RMR), or the calories that you burn while at rest (12, 24).

This leads to greater chances of weight regain over time, as well as the vicious cycle of repeated periods of weight loss followed by weight regain that so many chronic dieters experience — which commonly leads to feelings of despair.

Weight cycling is detrimental to mental health, and research has shown that repeated dieting and weight cycling can stress the heart and may lead to a higher risk of eating disorders, type 2 diabetes, and increased mortality (25, 26).


Cutting calories too severely can lead to negative side effects like nutrient deficiencies and fatigue. Low calorie diets rarely work for long-term weight loss and can lead to weight cycling, which negatively affects overall health.

Oftentimes healthcare providers and people looking to lose weight choose diets based on how quickly they can produce the desired results, failing to consider the long-term health consequences of overly restricting calories.

While choosing a restrictive, low calorie diet that delivers well below your daily calorie needs is likely to result in quick weight loss, keep in mind that some of that weight loss is in the form of muscle mass. Muscle loss and other metabolic adaptations can lower your RMR (12).

Large calorie deficits not only lead to unfavorable changes that make maintaining weight loss harder but also can take a serious toll on your emotional well-being.

The majority of research studies suggest that dieting doesn’t work and using healthier, less extreme weight loss methods is a better choice for supporting weight loss and weight loss maintenance over time.

For example, instead of cutting your intake down to 1,200 calories, which usually involves tracking every piece of food that crosses your lips, try a few of the following evidence-based, healthy weight loss tips:

  • Eat whole foods. Whole foods, including vegetables, fruits, beans, fish, nuts, seeds, and eggs, should comprise the majority of your calorie intake. Whole foods are packed with the fiber, protein, and healthy fats your body needs to thrive.
  • Cut out added sugar and fats. Reducing your fat and added sugar intake is a healthy way to promote weight loss. Common sugar- and/or fat-laden foods include soda, cakes, ice cream, candy, and sugary cereals (27).
  • Cook more meals at home. Rely less on take out, restaurants, and fast food and cook more meals at home. People who cook more meals at home tend to weigh less and have a healthier diet than those who eat more meals outside the home (28).
  • Increase daily activity. One of the best ways to promote healthy, sustainable weight loss is to create a calorie deficit by increasing the number of calories you burn. Try adding in daily walks outside, taking exercise classes, or joining a gym (29).
  • Work with a knowledgeable healthcare provider. Weight loss can be intimidating and stressful. A knowledgeable dietitian or other trained healthcare provider can help you lose weight in a healthful way without extreme restriction.

While losing weight using healthy, sustainable dietary approaches may take more time, it reduces the unfavorable adaptations that occur during extreme calorie restriction and can help increase your chances of keeping the weight off for good.


When trying to lose weight, using less restrictive methods can help you achieve healthy, sustainable weight loss.

A 1,200-calorie diet is a low calorie eating pattern that typically involves counting calories and eating reduced calorie foods to promote quick weight loss.

Although a 1,200-calorie diet is likely to promote short-term, rapid weight loss, metabolic adaptations that occur during calorie restriction make keeping the weight off long term extremely difficult.

What’s more, 1,200 calories is well under the average number of calories that most adults — even small women — need to fuel their bodies.

While diets providing 1,200 or fewer calories are a popular tool for weight loss, it’s better for your overall health to choose a diet that fuels your body in a healthy way and promotes slow yet sustainable weight loss that can be maintained for life.

How many calories do you need per day to lose weight? Calorie calculator online. Daily calorie intake for weight loss

Calorie counting is the most effective method of losing weight. When used correctly, it can give 100% results. Knowing the individual daily calorie intake, you can adjust the diet and achieve your goals faster.

Parameters affecting the choice of diet

The diet should be based on the characteristics of the body and the required amount of nutrients. To calculate how many calories you need per day, consider:

  • daily activity level;
  • age and gender, since men need to consume more calories than women;
  • availability of training;
  • figure parameters, which include height and weight;
  • habitual diet.

Calculate how many calories you need per day to lose weight, you can do it yourself using formulas or using an online calculator. For example, nutritionist Lidia Ionova not only explains each step in the calorie counting formula, but also teaches how to build a food pyramid. And the American doctor Holly Phillips is convinced that by finding out how many calories you need to eat per day, you can get rid of fatigue.

Thus, having the necessary calculations in hand and knowing how many calories you need to eat per day, you can adjust your diet and achieve the expected results faster.

Women’s and Men’s Daily Calorie Values ​​

Fats, proteins, and carbohydrates are three key micronutrients that provide the body with the energy it needs and support biochemical processes.

The female body requires less daily calorie intake than the male body. This is due to the inherent genetic ability to quickly gain weight for full-fledged procreation.

The norm of kcal per day for a woman is on average about 2000 kcal. If it is necessary to lose weight, 500 kcal or 10-20% are taken away from the calorie norm for different age groups of women with different activities and diets.

At the same time, the number of calories per day should be reduced gradually, otherwise a sharp decrease in the intake of substances necessary for the body can cause menstrual irregularities, a weakened immune system, slow metabolism or problems with the heart.

Table 1. Daily requirement for proteins, fats, carbohydrates and calories of able-bodied men and women

Group Age, years Men Women
Proteins, g Fat, g Carbohydrates, g Energy, thousand kJ Proteins, g Fat, g Carbohydrates, g Energy, thousand kJ
Total incl. animals Total incl. animals
Predominantly knowledge workers 18-29 91 50 103 378 11. 7 78 43 88 324 10.1
30-39 88 48 99 365 11.3 75 41 84 310 9.6
40-59 83 46 93 344 10.7 72 40 81 297 9.2
Light manual workers 18-29 90 49 110 412 12.6 77 42 93 351 10. 7
30-39 87 48 106 399 12.2 74 41 90 337 10.3
40-59 82 45 101 378 11.5 70 39 86 323 9.8
Medium duty workers 18-29 96 53 117 440 13.4 81 45 99 371 11.3
30-39 93 51 114 426 13. 0 78 43 95 358 10.9
40-59 88 48 108 406 12.4 75 41 92 344 10.5
Heavy manual workers 18-29 102 56 136 518 15.5 87 48 116 441 13.2
30-39 99 54 132 504 15.1 84 46 112 427 12. 8
40-59 95 52 126 483 14.5 80 44 106 406 12.2
Workers engaged in particularly hard physical labor 18-29 118 65 158 602 18.0
30-39 113 62 150 574 17.2
40-59 107 59 143 546 16. 3

1. The need for pregnant women (5-9 months of pregnancy) is on average 12.2 thousand kJ, protein – 100 g per day, including 60 g of animal origin.
2. The need for nursing mothers is on average 13.4 thousand kJ, protein – 112 g per day, including 67 g of animal origin.

In order to determine how many calories a day a man needs, it is necessary to take into account that they have an accelerated metabolism and are prone to rapid weight loss. Therefore, the diet for the representatives of the masculine gender should consist of a diverse set of products.

The average calorie intake per day for a man is 2400 kcal and may fluctuate due to age, intensity of exercise, lifestyle and weight. To lose weight, men, like women, need to consume 10-20% fewer calories than the prescribed norm.

The daily requirement for calories, as well as carbohydrates, proteins, fats for able-bodied women and men is presented in the table:

How many calories do you need to lose weight?

In order for the body to activate defense mechanisms by slowing down the metabolism, it is necessary to understand exactly what calorie deficit is needed for weight loss. Experienced nutritionists advise to calculate how many calories a person needs per day, and then subtract 10-25% from the results. More detailed calculations are given by Elena Morozova, a doctor and founder of the Slavic Clinic. She warns against reducing the daily intake to 1000 kcal, which often occurs on low-calorie diets.

It is important not to reduce the calorie content of the daily menu below the requirements of the basic metabolism, since such a process of losing weight will be accompanied by loss of muscle mass and general discomfort.

You can create a 40% daily calorie deficit for weight loss in a very fast way. But it should be remembered that the safe calorie limit without the supervision of a nutritionist and a doctor is 1800 kcal for men and 1200 kcal for women. Otherwise, a person will not only lose weight, but will reduce immunity and simply deplete his body. But for a short period of time, you can stick to a diet even for 1000 kcal, says the author of cookbooks Ekaterina Maslova – and gives a menu for quick weight loss for a week.

Calculating your daily calorie intake can be done quickly and easily using the online calorie calculator, which can be found on almost any website dedicated to nutrition or healthy eating.

Online Calorie Calculator

Daily Calorie Calculator per day will help you find out:

  • how many calories you need to eat per day for the body to function normally;
  • how many calories do you need to lose weight;
  • how many calories it takes to gain weight.

To calculate calories for weight loss, you must enter your height, weight, sex, age, level of physical activity. You don’t need to do anything else, the online calculator will do everything by itself.

Age: years

Gender: Male Female

Weight: kg

Height: cm

Activity: minimal/no physical activityBasic metabolism3 times a week5 times a week5 times a week (intensive)Every dayEvery day intensively or twice a day Daily physical activity+physical work

Formula: Mifflin – San Jeor Harris-Benedict

The calculation of daily calorie intake can be made using two different methods: one of the most modern, according to the Mifflin-St. Geor formula, derived in 2005, and according to the older, but popular among nutritionists in our time, the Harris-Benedict formula, known since 1919.

Drying the body

Drying the body is a set of actions, the implementation of which reduces the percentage of adipose tissue in the body, maximizes muscle relief, and also burns subcutaneous fat.

Drying the body for girls and men consists in cutting carbohydrates in the diet, drinking more water, increasing the consumption of high-protein foods and sports nutrition.

According to the advice of experienced nutritionists and trainers, in order to saturate the body with useful elements with protein, it is necessary to consume vegetables and fiber, as they combine perfectly and enhance the assimilation of each other.

To draw up the correct diet, you should calculate the BJU online using a calculator. Thus, you can find out not only the individual need for calories, but also the necessary ratio of proteins, fats, carbohydrates, based on the goal pursued.

The application of knowledge about proper nutrition and diet planning is one of the main factors influencing the process of weight loss. The effectiveness of losing weight depends on many circumstances, but only a comprehensive approach to the existing problem will help to solve it effectively.

Count calories and lose weight. Body Mass Index Calculator

Why can some people eat whatever their heart desires and never get fat, while others only need to sniff an extra bun, and the hated fat on the tummy is right there? It’s just how our life is arranged, this is how the metabolism works: the calories consumed are burned without a trace or accumulate in the body – and there is no third way.

Calorie calculator for weight loss online

Disappointing conclusion number one: there are lucky people in the world who can safely score on losing weight and counting calories.

Are you one of those lucky ones? Then read on to find out. And to learn to use this rule every day.

Positive conclusion number two: If you want to control weight, count calories!

Do it every day, without breaks and days off! You ask, is it possible to lose weight without daily calorie counting? We answer: yes, you can, but only for a short time. Because then all the lost kilograms will come back, and they will even take a couple of extra ones with them. Familiar story? That’s it! It turns out so because, while on a diet, we limit ourselves in food. The body does not like it – it does not receive the substances it needs, it experiences stress. He starts to panic and then, at the end of a low-calorie diet, actively accumulates fat, otherwise, God forbid, starve again.

So what does give you daily calorie count ?

Slimness: you will start to like your own reflection in the mirror
Health: you will forget about doctors and pills
Youth: your body will look younger and full of energy

So you need to count calories, but how to do it right ?

First, let’s figure out what “calories” are. And this is nothing but energy for our body. Calories enter our body with food and are spent for their intended purpose. That is, the body “burns calories”, using them for physical and mental activity. And those calories that are not consumed by him remain in the body “for a rainy day”, in reserve – already in the form of fats. And the lack of calories provokes the body to more active weight gain (plus it also leads to malaise and weakness). What follows from this? –

Life-affirming conclusion number three: In order not to provoke the body to gain excess weight, you need to know your daily calorie intake and maintain a balance of calories.

If you are interested not in a one-time result, but in a long-term one, if you want to maintain health and youth, then calorie counting will be the only right choice on the way to an ideal figure.

Everyone has their own daily calorie intake, it depends on many factors: age, gender, weight, height, lifestyle, as well as individual characteristics of the body. Our online weight loss calorie calculator will help you determine exactly how many calories you need per day to stay slim.

Calorie counter online will help both women and men. With it, you can:

– reduce weight correctly

– gain weight correctly

– maintain optimal weight

The daily calorie intake depends on the goal.

Although our weight loss calorie calculator is very accurate, remember that the error in the results can be quite high . This is due to the fact that it is impossible to determine with 100% accuracy the rate of calorie burning by your body. To minimize errors, we suggest using the online calorie counter in this way:

1. Start losing weight or gaining weight with the daily calorie content that the calculator suggested.

2. If weight loss does not decrease after one or two weeks, reduce your daily caloric intake by 100-200 calories. Continue lowering until your body weight begins to drop.