My BMR Is 1200 Calories: How Do I Lose Weight?

If you’ve determined that your BMR is 1200 calories, here is how you can lose weight effectively: 

If you have a BMR of 1200 calories, you can lose weight by creating a deficit through calorie restriction and increased activity.

When you increase the calories burned through exercise and eat less than the total amount of calories your body burns, you create a negative energy balance, which will result in weight loss.

However, it is important to note that you may not get the results that you desire if you have not accurately calculated your BMR.

There are variables to consider that can affect your BMR such as a history of dieting, hormone imbalance, underlying medical condition, and your current body composition.

In addition to this, if you are burning a substantial number of calories in a day and your energy expenditure (how much you burn through exercise) is significantly higher than your BMR, you might experience some negative side effects caused by under eating.

Therefore, in this article, we will discuss:

  • Can you lose weight if you eat your BMR of 1200 calories?
  • Is there a risk of eating under your BMR of 1200 calories?
  • Factors that can affect your BMR calculation
  • How do you lose weight with a 1200 calorie BMR? (4 Steps)
  • Exercising with a 1200 BMR: What to Consider

Can You Lose Weight If You Eat Your BMR of 1200 Calories?

In order to experience weight loss, you must create a negative energy balance and consume less calories than you burn in a day. If you eat your BMR of 1200 calories, then you should lose weight due to the fact that you will be eating below your Total Daily Energy Expenditure (TDEE), which will create a calorie deficit.

For example, if a 30-year-old, 120-pound woman who is 5’3” tall has a BMR of 1200 calories, then this is the number of calories that she must consume in a day for her body to function. However, the amount of calories that her body needs increases if she adds any sort of activity to her day.

If this woman were to partake in moderate amounts of exercise 4-5 times per week, then her daily energy requirements will increase to around 1800 calories per day.

Therefore, if she were to consume her BMR of only 1200 calories, then she would be creating a substantial 600 calorie deficit that would result in weight loss.

In addition to this, the Thermic Effect of Food (TEF), the amount of calories you burn by digesting your food, can account for around 10% of total calories that you will burn in a day.

This percentage can increase to around 20-30% when you are eating high amounts of protein, due to the fact that protein takes more energy for your body to digest.

While you can lose weight by eating your BMR of 1200 calories, it may not be necessary if your TDEE is significantly higher than your BMR.

For most people to experience weight loss, it is only necessary to create a calorie deficit of around 250-500 calories per day in order to see results.

Therefore, if the amount of activity that you partake in during your day along with the thermic effect of your food significantly increases your TDEE, then it is most likely not necessary to eat as low as your 1200 calorie BMR in order to lose weight.

Is There a Risk of Eating Under Your BMR of 1200 Calories?

Is there a risk of eating under your bmr of 1200 calories

Your BMR is the minimum number of calories that your body needs in a day in order to perform necessary life sustaining functions. 

With this in mind, it is not recommended that you consume less than this minimum requirement, as it could result in some negative side effects.

Some consequences of consuming less calories than your body’s minimum requirement for an extended period of time are:

  • Reduced energy and workout performance
  • Hormone and reproductive problems
  • Disrupted sleep
  • Slowed gut motility and constipation
  • A decreased metabolism
  • A suppressed immune system

1. Reduced Energy and Workout Performance

Due to the fact that calories are your body’s main source of energy, if you are eating your BMR calories but burning exponentially more through exercise, then you might experience low energy levels due to lack of fuel.

For example, if the woman mentioned above participated in high amounts of daily exercise where she burns around 1000 calories per day, then eating her BMR of 1200 calories would create an extreme calorie deficit. The consequence of this would be reduced energy, along with decreased performance in her workouts.

2. Hormone and Reproductive Problems

When you eat in an extreme calorie deficit for a prolonged period of time, you run the risk of creating hormone imbalance within the body, along with fertility problems.

When you decrease calories dramatically under the amount that you burn in a day, reproductive function particularly in women can become suppressed. This can affect the regularity and consistency of the female cycle.

In addition to this, an extreme calorie restriction can increase cortisol levels in the body which can cause hormone imbalances in the body such as HPA axis dysfunction or “adrenal fatigue”.

3. Disrupted Sleep

Sleep is a crucial component of overall health and vitality, and if you are in an extreme calorie deficit, your sleep patterns can be negatively affected.

Extreme calorie restriction has been linked to disruptions in sleep quality, which can ultimately affect your recovery.

If you are eating in a deficit and begin to notice disruptions in your sleep, it may be an indication that you need to reduce your calorie deficit slightly.

4. Slowed Gut Motility and Constipation

If you are consuming a low number of calories, you may also experience the symptom of reduced gut motility and constipation. One of the reasons for this is that when you consume less food, there is less waste in your digestive tract.

Another reason that someone might experience constipation while eating a low-calorie diet is due to the fact that this caloric restriction is causing a reduced metabolic rate. This can even occur if the individual is consuming enough fiber in their diet.

In order to ensure that your bowels remain regular, make sure that calories are not taken too low, even when the goal is weight loss.

5. A Decreased Metabolism

If you regularly eat far fewer calories than your body burns in a day, you are at risk of decreasing your metabolism, which can make it more difficult to maintain or lose weight in the future.

While calorie restriction is useful in certain instances, if taken too far, it can decrease the number of calories that your body is able to burn by up to 23%.

In addition to this, the metabolic reduction that a calorie deficit can cause will often persist even when the calorie deficit has ended.

This reduction in metabolism is most often caused by decreased muscle mass that can occur during dieting.

In order to mitigate any unwanted muscle loss, aim to include an ample amount of protein in your diet in conjunction with a consistent weight training routine.

6. A Suppressed Immune System

If you are eating in a calorie deficit, this increases your risk of not receiving specific nutrients that are needed to support a healthy immune system and fight off infections and illnesses.

Since we know that an extreme calorie deficit can suppress your immune system and make you more susceptible to illnesses such as the common cold, it is best to not remain in a deficit for more time than necessary, and return to maintenance calories as soon as you have achieved your desired goal.

Factors That Can Affect Your BMR Calculation

Did I Calculate My BMR Correctly?

If you have calculated your BMR to be 1200 calories, and you are eating this number of calories and not losing weight, you must consider that you might not have calculated your BMR correctly.

The easiest way to calculate your BMR is with a formula such as this one:

● Men: (88.4 + 13.4 x weight) + (4.8 x height) – (5.68 x age)

● Women: (447.6 + 9.25 x weight) + (3.10 x height) – (4.33 x age)

If you wish to skip the manual equation, you can also use our BMR calculator. This calculator considers your age, height, weight, and sex.

Other Factors That Can Impact Your BMR

However, if you have correctly calculated your BMR at 1200 calories, but you are not losing weight despite consuming this amount, then the following factors must be considered.

A few factors that can affect your BMR calculation are:

  • Your history of dieting
  • Hormone imbalance or underlying medical condition
  • Your current body composition

1. Your History of Dieting

If you have previously been in a calorie deficit, or you have a long history of dieting, then it is possible that your BMR calculation is inaccurate, and your current BMR is actually lower than you thought.

When you are in a calorie deficit for a long period of time, the body can adapt and your BMR can slow down.

Therefore, if you are under the impression that your BMR is higher than it actually is, then you might be eating more than you should in order to experience weight loss.

2. Hormone Imbalance or Underlying Medical Condition

Certain hormone imbalances or medical conditions can have an effect on your BMR. Some examples of this include ailment like hypothyroidism, which can result in an underproduction of the thyroid hormone, causing the metabolism to slow down.

If you suspect that you may be dealing with a medical condition or hormone imbalance that is causing a shift in your BMR, it is advised that you seek out the help of a doctor or health care professional that can work with you to help you bring your body back into balance.

3. Your Body Composition

While your BMR can give you insight into how many calories your body burns based on your age, height, weight, and sex, it is missing a large part of the picture.

Your body composition, in particular how much muscle mass you have on your body, can be a determining factor in how many calories you burn.

The more lean body mass that you have on your body, the more calories that your body will burn at rest. In contrast to this, if you have more fat mass on your body compared to muscle, your BMR will be lower.

This means that if you have two people that are identical in age, height, weight, and sex, if one of the individuals has more muscle mass on their body, their BMR is going to be higher than the other individual.

How Do You Lose Weight with A 1200 Calorie BMR? (4 Steps)

How do you lose weight with a 1200 calorie bmr (4 steps)

If you have a BMR of 1200 calories, there are a few simple and effective steps that you can take in order to facilitate weight loss. 

The most important factor for weight loss is to create a calorie deficit. 

Below are some steps that you can take to create a deficit with a 1200 calorie BMR.

  • Calculate the calories you burn through exercise (both EAT and NEAT)
  • Determine an appropriate calorie deficit
  • Calculate your macronutrient intake and consider increasing protein intake
  • Be consistent with your deficit

1. Calculate the Calories You Burn Through Exercise (Both EAT and NEAT)

In order to determine the total amount of calories that the body burns in a day, you must have a good idea of how many calories you are burning in a day through exercise activity (Exercise Activity Thermogenesis or EAT) and non-exercise activity (Non-Exercise Activity Thermogenesis or NEAT).  

A simple and easy way to do this is to use the Harris-Benedict Equation, which will help you to determine how many extra calories you are burning in a day through exercise. 

In order to do this, simply multiply your BMR with the number that accurately resembles your activity level:

  • Sedentary (minimal or no exercise): 1.2
  • Lightly active (light exercise or sports 1-3 days/week): 1.375
  • Moderately active (moderate exercise or sports 3-5 days/week): 1.55
  • Very active (intense exercise or sports 6-7 days a week): 1.725
  • Extremely active (Intense exercise + physically demanding job):1.9
For this example, we will use the woman mentioned above who has a BMR of 1200 calories. In this case, she is a moderately active woman which means that the amount of total calories she burns throughout the day with her exercise included is:

1200 x 1.55 = 1860 calories to maintain her weight.

Once you know your maintenance calories, you will be able to determine an appropriate calorie deficit depending on your goal. Another way to determine your TDEE is through an online calculator like this one here.

2. Determine an Appropriate Calorie Deficit

Once you have determined the number of calories that you need when you have factored in energy that is burned through exercise, you can properly calculate how many calories you will need to eat in order to reach your weight loss goal.

If you are looking for slow but sustainable weight loss, then you can try reducing your calories by around 250 calories. For a more aggressive cutting phase, you can reduce your intake by about 500 calories.

If we refer to the example above, that would mean that this woman would have to consume around 1360-1610 calories in order to achieve weight loss. As you can see, she does not have to reduce her calories down to her BMR in order to achieve weight loss.

3. Calculate Your Macronutrients and Consider Increasing Protein Intake

Once you have determined your calorie deficit for weight loss, you can then get specific on the types of calories that you want to consume.

It is important to have a proper balance of protein, carbohydrates, and fat in order to meet your body’s daily requirements.

A popular macro split to balance all three nutrients is 50% carbohydrates, 30% protein, and 20% fat. 

This macro split can be manipulated depending on personal preference along with individual goals. For example, if the goal is weight loss, then you might benefit from increasing your protein intake slightly, while decreasing your carb intake.

The higher your protein intake is, the more calories your body will burn through digesting your meals. 

With that being said, carbohydrates and fat are both essential nutrients that we do not want to neglect simply to get more protein in. Having a balance of all 3 nutrients will help with overall health, along with satisfaction and compliance to your diet.

4. Be Consistent with Your Deficit

 When it comes to weight loss, consistency with your calorie deficit is key. 

If you choose a calorie deficit that is too low, you are less likely to stick to your diet long term, and you are more likely to experience “falling off the wagon” or even binge eating.

In order to be consistent with your cutting phase, choose a reasonable calorie deficit that is not too low, eat meals that are composed of whole foods and that are full of protein and fiber, and make sure that you create meals that you truly enjoy.

Exercising With 1200 BMR: What to Consider

If you are incorporating exercise into your routine with a BMR of 1200 calories, you may want to consider including specific types of exercise in order to help increase your BMR.

For example, including weight training in your routine will help you to build lean muscle mass, which will help to increase your BMR. In addition to weight training, including HIIT cardio into your routine will also increase your BMR.

These types of exercises are favored if you have a low BMR in comparison to exercises like long distance running, which can decrease BMR and metabolism over time.

Considering all of this information, remember that as long as you are creating a deficit through exercise and calorie restriction, you will experience weight loss, even with a BMR of 1200 calories.

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About The Author

Colby Roy

Colby Roy is a holistic health and nutrition coach. She is certified through Precision Nutrition and has a passion for all things nutrition and healing the body. More specifically, Colby likes to work with clients who want to optimize their gut health and energy levels.

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