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Does Your Body Burn More Calories When Sick?

Does Your Body Burn More Calories When Sick?

When you’re sick, your body can burn additional calories as it fights off illness. Whether or not you burn extra calories depends on the severity of your symptoms, and whether or not a fever is present.

If you have a fever, your body is burning more energy in order to cool itself down and rid the body of infection. On average, for every degree Celsius that your core body temperature increases, your caloric expenditure increases by 7-10%.

Feverishness can last from several hours up to 1-2 days and result in up to an extra 400-600 calories burned per day, depending on how high the fever is.

Without a fever present, it’s still possible to burn more calories if you are extremely symptomatic. Thinking about fighting off a cold or flu may make you lose your appetite which can cause a slight reduction in caloric intake overall.

Additionally, physical activity may be limited while ill due to fatigue and weakness – resulting in fewer calories burned through exercise than usual.

Finally, it’s important to note that eating the right type of animal-based or plant-based foods when sick can help boost immune function and speed up recovery. So eating nutritious meals (which will likely increase caloric intake) is still recommended despite any potential added caloric burn from being sick.

Do You Burn More Calories When You Have A Fever?

The short answer is yes; when you have a fever, your body burns more calories. A fever is a strategy your body uses to increase its immune response. To do that, it needs to raise its temperature and in order to do that, it must burn extra calories. This raises the basal metabolic rate (BMR), which means you are burning more calories.

In addition to burning extra calories from the fever itself, there are other factors that can contribute to an increase in calorie burning and weight loss such as decreased appetite or dehydration caused by the fever.

Other processes within the body may be heightened with an increased immune response resulting in a few extra burned calories. So yes, if you have a fever, your body is hard at work trying to fight it off and burning more than its usual amount of calories in the process.

How Many Calories Do You Burn When You Have A Fever?

When you have a fever, your body’s basal metabolic rate (BMR) increases significantly, meaning that it burns more calories than usual. This is because your body is working hard to fight off the virus or bacteria that is causing the fever. But how many extra calories does your body burn when you have a fever?

It all depends on your age, gender, and weight. Generally speaking, if you’re a 25-year-old male who is 5’8″ and 150 pounds then your normal BMR is about 1,640 calories per day.

However, if you have a fever of 101.3 ºF (which is slightly higher than the normal body temperature of 98.6 ºF), then your BMR would increase by 21% compared to usual – That equals 344 extra calories burned while having a fever!

So if you’re looking to lose weight while also dealing with a sickness like the flu or common cold, then taking note of your increased metabolism due to having a fever can be helpful in allowing you to reach meal goals or stick with an exercise program as well.

Factors Influencing The Number Of Calories Burned By A Fever.

When you have a fever, your body works overtime to fight infection and restore balance. This extra work requires more energy, which translates to burning more calories than normal. There are several factors that influence how many additional calories your body burns during a fever.

  1. First and foremost, the size of your body matters. If you are smaller in stature then you burn fewer additional calories through a fever than someone with a higher BMR (Basal Metabolic Rate). On the other hand, bigger people with higher BMRS tend to burn more additional calories when running a fever.
  2. In addition, hormonal differences between men and women also play an important role in determining how many additional calories their bodies burn due to fever.
  3. Women typically have lower BMRs than men (unless they’re very strong), so the percentage increase in core body temperature from a fever is often fewer extra calories burned.
  4. Finally, the intensity of the fever will dictate how much extra energy is needed to combat it and thus how many additional calories will be burned while doing so.
  5. The higher the human body temperature of your fever is, the greater the percentage increase in calorie burn as your body works to correct itself – although this can be dangerous as well.

Do You Burn More Calories When You Have A Cold?

Although you won’t burn as many calories when you have a cold as you would if you had a fever, there are still some ways in which having a cold can affect your calorie balance.

The main reason for burning extra calories during fever is because of the extra work that your body has to do to increase its temperature–and since you don’t experience this during the common cold, it’s unlikely that you will be burning more calories.

However, other factors of having a cold like appetite changes or your body working hard to fight the infection may lead to temporary weight loss due to fewer consumed calories.

Your lack of appetite during sickness can often be affected greatly by a cold and if you’re only eating when hunger strikes, then you’ll likely end up consuming far fewer calories than normal which could lead to lean body weight loss.

Besides that, there may also be some calories used in fighting the infection itself–just not as much as with full-blown fever since your body is not trying to raise its temperature systemically.

When You’re Sick, Do You Lose Weight?

It’s common to temporarily lose weight when you have a cold or illness, but it’s important to understand why. Most of the weight you lose is water weight due to dehydration and not actual body fat or muscle mass.

However, if your eating habits change drastically while you’re sick, such as eating much less than usual, then it’s possible that you could lose actual body fat or lean body mass.

This can happen in combination with running a high fever. When there’s less quality food in your body and your glycogen stores are depleted, your weight will go down.

In order to avoid losing additional body fat or muscle during a fever, be sure to eat an extra amount of food so that it covers the extra energy your body needs in order to run the fever.

When You Have A Cold, Should You Eat More?

When you are suffering from a cold or any other type of illness, it is important to consider your diet. You may be tempted to skip meals, but recent studies have shown that reducing calorie intake during illnesses can worsen symptoms and lengthen the duration of time you will be sick.

Therefore, it is best to listen to your body and eat extra when necessary in order to get better faster.

Soup, fruit, nuts, and seeds are all great options for snacking while you’re sick as they provide essential calories and electrolytes that can help strengthen your body. Soup is particularly soothing and maybe more enjoyable than plain food when you don’t feel well.

Fruits contain vitamins that can help reduce symptoms and give your immune system a boost. Nuts and seeds provide healthy fats as well as filling protein which can help keep you feeling full between meals.

What Should You Eat When You’re Sick?

When you’re sick, it’s important to focus on eating nutritious foods that will help your body fight off the germs and boost your immune system. Make sure to drink plenty of water which will help keep you hydrated.

There are certain foods that can provide your body with the essential vitamins and minerals needed to help your recovery.


Garlic is a powerhouse of nutritional benefits and can be especially helpful when you’re feeling under the weather. It’s got anti-viral and antibiotic properties, making it very effective in fighting off infections and boosting your immune system.

The best way to incorporate garlic into your meals is to crush 2-3 cloves with a blender, or food processor, or by using the palm of your hand to press down on the clove. Garlic goes great when added to mushroom and tomato sauces, giving them an extra kick of flavor as well as natural medicinal benefits.


Honey is a common ingredient in many households, and it can be especially helpful when you’re feeling under the weather. Honey has a lot of antibacterial and antimicrobial properties that can help boost your immune system while also providing some relief from common symptoms associated with sickness.

No matter how you choose to enjoy this age-old healing elixir, rest assured that adding a bit of honey to your diet when you’re feeling a bit under the weather can give your body the boost it needs to get back on track.

Chicken Soup

When you’re feeling under the weather, chicken soup is one of the best things to eat (just not if its left out overnight). It’s not only comforting-it’s also good for you. Chicken soup can help you stay hydrated and provide important electrolytes like potassium, which is essential for maintaining fluids and energy levels in the body.

This can help improve circulation, reduce inflammation, and even fight off pathogens in the body that could be making you feel worse.


A protein-rich food is an important nutrient to include when you’re sick. Protein-rich sources like poultry, fish, eggs, and dairy should be included in each meal for optimal benefit. For men, two palms of high-protein dense foods should be eaten per meal, and for women, one palm.

This extra protein helps support the body’s natural inflammation response by limiting the amount of glucose used for energy during this time.

Vitamins And Minerals

Vitamins and minerals are essential when you’re sick. Vitamins play a critical role in the strength of your immune system, which helps you fight off illness.

To ensure your diet contains all the vitamins your body needs to remain strong, focus on getting enough Vitamin B12, B6, C, D, E, B9, and A. Multivitamins with minerals like iron, copper, zinc, and magnesium can also help boost and strengthen your immune system so it is prepared to fight off the sickness or virus.


Probiotics are beneficial bacteria that can help to improve the health of the digestive system when we’re under the weather.

When we eat plenty of food rich in probiotics, they work to balance our gut bacteria and promote overall health. This is especially important when you’re sick and your body needs help fighting off infection.

What Shouldn’t You Eat When You’re Sick?

When you’re sick, it’s important to know what type of food intake you should avoid or consume in moderation. Eating unhealthy foods can make a bad situation even worse and lead to further health complications. Here are the foods to be aware of when facing an illness or sickness:

  • Caffeine: Drink coffee in moderation as it can dehydrate the body if consumed too much.
  • Fatty Foods: Avoid high amounts of fatty meals and foods rich in carbohydrates. Excess fat consumption during the infection is difficult to break down and can put a strain on your gastrointestinal system.
  • Sugary Drinks: Stay away from highly-processed fruit juices from the store as these may slightly inflate your immune system while not providing much nutritional benefit.

Hey'all I'm Amy, a born foodie and diagnosed with celiac disease 7 years ago. I refused to cave into tasteless, boring gulten free food and create my own!
On my blog you'll find info & cool facts along with recipes, all on gluten free foods!

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