What Happens When You Starve Yourself To Lose Weight

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Medically reviewed by Kimberly Langdon, MD

What Happens When You Starve Yourself To Lose Weight-1

If you are among the ones who gain weight just by watching someone else eat or if your metabolism is slow as a sloth, then you might have jumped onto the bandwagon to try every new weight loss method that is out there. The world we live in craves instant gratification. From fast foods to fast weight loss methods, we need something that works almost immediately. There are a dime a dozen diets and we get introduced to new forms of exercises every now and then. Most of them go with all-or-nothing methods. There are many methods to support weight loss such as exercise, proper diet, adequate sleep, metabolism boosters, thermogenic foods, and  CBD oil help lose weight. But, most of us trip into starvation mode once in a while, with the belief that eating little to nothing can help us lose weight. But how true is that? Well, continue reading this article to find out.

What Happens When You Starve Yourself To Lose Weight?

Starvation may seem like a good weight loss method, but it does more harm[1] than good to your body. While burning fat, it also decreases the lean muscle, causes bone weakening, and negatively impacts your overall health. There are many better and healthier ways for you to lose weight and starving yourself is not one of them.

What is starvation? How does it affect my body?

Starvation is a natural response from our body to long-term calorie restriction. It is our body responding to a calorie deficit by lowering calorie expenditure to balance energy and stop starvation. This physiological process is technically called adaptive thermogenesis.

Why do we choose starvation?

Ever heard of “calories in versus calories out[2]? It is a rule of thumb for weight loss. If you consume more calories than you burn in a day, you will gain weight. If you spend more calories than you eat, you will slim down. This marks the importance of calorie deficit, and it is the best way to lose weight. All weight-loss diets are aimed at reducing the intake of calories. But with a die-hard approach, one tends to take much lower calories than they should be. When your calories are greater than calories out, our body loses fat and views it as the beginning of starvation. Our body struggles to stop that from happening.

Meanwhile, our body and brain respond in a way that we hate. By increasing our hunger, we tend to eat more. Which affects the calories burnt. By being starved, your body reduces spending calories and restores to balancing energy. This hinders weight loss even when you continue to restrict calories[3].  

What happens when you starve?

One study showed that people who did starvation diets[4] as a way to lose weight, consuming 50% of their energy needs for 3 weeks, did reduce their body weight. However, they also lost their lean muscle by 5%. And if this state of starvation is continued constantly, there will be a decrease in lean muscle and the size of organs by 20%. Altogether, weight loss by starvation can make you lose substantial amounts of both lean muscle mass and lean body mass, which comprises bones, water, and organs. A decrease in the mass of your bones can cause bigger problems like a decrease in bone density. And when this happens, you are more prone to injury. But with the other way around, such as increasing the musculature, bone density, and overall strength one can improve overall health and get rid of the stubborn fat. If you are someone who is practicing starving then you are about to read bad news but for the good.

Research in animals  has shown that calorie restriction can slow down the body’s metabolism[5]. Moreover, muscle mass tends to decrease. Muscle is metabolically busy and burns calories day and night. However, the slowdown in the calories spent is larger than the decrease in muscle mass alone. The body works efficiently, but on very minimal energy than it used to. That’s how starving makes you spend fewer joules even when you perform an intense workout like skipping rope. So, this marks the importance of a good metabolic rate.

major metabolic changes

Furthermore, starvation leads to major metabolic changes, for example, resting metabolic rate and metabolism are linked to lean body mass. So anyone with greater body mass will need more energy to function daily and will have a larger basal metabolic rate (BMR). But losing weight decreases BMR. This goes to say that our body needs a certain number of kcals to maintain lean mass. When gone below, our body is constrained to break down the muscle stores to make energy. This shows that calorie diets can have deep-seated negative effects on the body. 

Lastly, during starvation, the body fails to maintain blood sugar levels. This drop-in levels of glucose links to a decrease in insulin and a spike in glucagon levels[6]. Which in turn leads to the release of more glucose by the liver into the bloodstream. And if the body continues to be in this mode, over a period of time, it may lead to many side effects associated with diabetes. It’s even worse for people over 45. 

What is set point theory and collateral fattening?

According to set-point theory[7], everyone has a standard weight the body is set to. And this relies on individuals’ DNA, environmental influences, and genetic effects. Thus, when we try to lose body fat, the body works hard to preserve that weight, despite extreme measures taken to lose weight loss. It is a feedback mechanism by our body. Furthermore, once a person stops a low-calorie diet and starts to eat a meal that has a normal calorie diet. They can undergo collateral fattening, which is when weight loss forces overeating to the extent of regaining fat.

This happens because weight loss eventually focuses on weight gain. Due to loss of weight from the fat-free mass. Fat-free mass includes mass in the body that is devoid of fat, such as organs, bones, and lean muscle. For this reason, the body begins to work to rebuild the lost mass. This activates collateral fattening, which increases appetite[8]. 

4 ways our body burns calories

  1. Basal metabolic rate: The number of calories our body uses to carry out vital functions like heart rate, breathing, and brain function.
  2. Thermic effect of food: The number of calories burnt to digest food, which accounts for about 10% of calorie intake. 
  3. Thermic effect of exercise: The number of calories burnt through physical activity.
  4. Non-exercise activity thermogenesis: The number of calories burnt to change postures and fidgeting.

When you starve, or lose weight the levels of all these are decreased. It happens due to a reduction in both conscious and subconscious movement. Moreover, due to major changes that occur in the functions of the nervous system[9] and hormones. And the hormone levels that decreased are thyroid hormone, leptin, norepinephrine.

How to avoid metabolic slowdown and lose fat?

There are several ways one can mitigate the effect of weight loss without going hungry or starving yourself to death. Like eating fewer carbohydrates, cutting on sweets, junk, and unhealthy fats. Eating small meals throughout the day, eating healthy meals that are rich in Nutrients. Our body needs all seven classes of nutrients such as proteins, carbohydrates, fats, vitamins, minerals, water, and fiber. So food that is rich in minerals and vitamins can make your body run like the wind. Stay active and Hit the gym, drink plenty of water. Over some time, you will see less fat being stored which will lead to lighter and energized you. 

Nutrients dense meal for weight loss

Many people do not meet the daily protein requirements. A nutrient-dense meal is as important as a good workout. Proteins are the gold mine when it is about losing weight. When you consume them adequately, you can reduce the calories in (appetite) and increase calories out (boost metabolism) by 80-100 calories a day[10]. Moreover, it can curb cravings for sugar and junk, prevent late-night snacking and overall intake. Furthermore, it prevents the long-term adverse effects of weight loss. And most importantly, they prevent muscle breakdown for energy. By doing so, muscles are conserved, in turn preventing metabolic slowdown. Isn’t this a healthier way to burn fat than starving?

Elliptical workout to burn overall body fat 

Many people tend to overlook the elliptical machine only because they do not know how to burn more calories on the elliptical. If you are someone who lacks time, jump on this machine to reap its benefits. Studies, in subject to individuals weight, proved that one could burn about 270-400 calories in 30 minutes[11]. Besides burning body fat, this machine can activate both the upper and lower body. Elliptical workouts can be both aerobic and HIIT and build good stamina and endurance. yes, you get the best of both worlds. Furthermore, exercise stimulates the brain cells and forms new neural connections. 

Lift weights to drop the body fat

Lifting weight is by far the most effective resistance exercise. Resistance exercise doesn’t always have to be lifting weights, but bodyweight exercises work well too. Studies prove that resistance training, as inactivating muscles against resistance, can give you major benefits when you are on a diet. In studies have shown that resistance exercise, as in exerting your muscles against resistance, can have major benefits when you’re on a diet. Studies report that resistance exercise can maintain metabolic rate[12], muscles, and strength which weight loss is known to decrease. Resistance exercises can prevent this from happening.

Short-term weight loss results by starving or by going hungry could be exciting, but we seem to lose sight of the bigger picture in search of instant results. Starvation mode is real. But it is overrated and not as potent as many people think. We seem to ignore the importance of health and gradual weight loss goals that are sustainable. Crash diets, Starvation diets may help you lose stored body fat initially, but at the cost of harming your health. They do more harm than good. Moreover, you gain back all the fat that you lost in no time. In lieu, one can eat healthy food instead of starving. Eating healthy and mindfully can go a long way.


+ 12 sources

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Written by:

Lakshmi Vemuri

Medically reviewed by:

Lakshmi Vemuri holds a bachelor’s degree in Dentistry. She is also a published author of several Food and Wellness books. Lakshmi has a profound interest in alternative medicines, various forms of physical exercise, mental health, diets, and new inventions in medical sciences. Besides being a dentist, Lakshmi is passionate about gardening and is an environmental enthusiast