Eating Too Little Calories But Not Losing Weight – Undereating and Why

As a normal girl struggling with her weight throughout her life, I was shocked to see that Stephanie, a fitness guru and avid weightlifter struggle with the same issues that I faced: undereating

After watching this video that Stephanie shared a few days ago, I decided to share a 3-part blog series on (1) Understanding what undereating is, (2) How it affects your health and (3) Taking care of your skin while dieting. 

5,000 Calories a Day? What A Dream!

In the video, Stephanie seems to be living the life and eating up to 5,000 calories daily. The typical calorie requirement of females range between 1,500 to 2,500 a day, depending on her age, height, weight, genes, physical activity and other factors. Now, one would think that she is eating high-calorie food such as fried chicken, pizza and processed food to hit that number - alas, she eats mostly healthy and whole food. Here’s a calorie chart for gauge on how much she actually eats in a day:

Food Calories for Weight Loss.jpg

Now… a healthy meal of brown rice, broccoli and chicken breast range between 300 to 500 calories, depending on the sauces, condiments and garnishes you use. Why then does Stephanie eat so much? As she explains in the video, she has been consistently undereating and controlling her portion sizes in order to maintain a ripped physique. As empowering as the fitness community can be, it can be equally demoralising when you have haters on the net telling you how you should look like and what you should eat.

A prolonged period of undereating has led to Stephanie being constantly hungry and unfulfilled - she has done multiple 10,000-calories cheat day challenges and succeeded with ease. However, these cheat days has done nothing to ease her hunger on her non cheat days. Thus, she is now trying the all-in approach: eating to satiety everyday to bring her body back to its original state and work her way back to a normal weight again.

The Importance of Knowing What Chronic Undereating Is

I learnt that undereating can cause difficulty in losing weight and even subsequent weight gain the hard way. Ironically, many people struggle to lose weight because they underestimate the amount of food they eat: a few chips there, some cake and that sweetened coffee you didn’t think had calories all add up. However, undereating is a thing: and simply put, it is eating so little calories your body panics and reduce its energy expenditure to keep you alive. 

Many sources tell us that losing weight is just a matter of increasing your calorie expenditure through exercise and reducing calorie intake through eating less. What happens when you eat too little and exercise too much?  

What Does Undereating Mean? 

As a general rule of thumb, a minimum of 1,200 calories daily is needed. However, this guide may not be helpful if you happen to be taller, bigger and require more calories in general to maintain your daily activities. Hence, it is always useful to find out your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) – which you can easily do online. 

 Basal Metabolic Rate 

Basal Metabolic Rate Losing Weight

This is the amount of energy if you lie in bed and do nothing at all. A simple comparison is the amount of gas an idle car consumes while parked. For most people, more than 70% of total energy (calories) burned each day is due to BMR. Physical activity (exercise, commuting, daily activities) makes up 20% of expenditure and 10% is used for the digestion of food, also known as thermogenesis.

As seen from the chart, people of a higher mass expend more energy - thus leading to a higher BMR. As we lose weight, however, our BMR drops and therefore lead to increased difficulty in losing weight the more we near our weight goals.

Total Daily Energy Expenditure 

Total Daily Energy Expenditure TDEE.png

TDEE = BMR + Physical Activity + Thermic Effect of Food 

You can never out-train a bad diet – since physical activity only make up 20% of your calorie expenditure in a day, it is difficult for you to burn that 1,000-calorie meal you had at lunch.

By knowing your TDEE, it is typically advised by doctors to never go beyond a 500-calorie deficit. For example, if you require 2,000 calories a day, a healthy gauge would be to achieve that deficit by reducing food intake by 300 calories and burning off 200 calories through exercise. The bigger the calorie deficit, however, the faster you see results, of course. 

We all want results, now. However, your body was created to keep you alive. If it detects that you are taking in less food than you require, and/or using all of it up on a daily basis, your body can only conclude that you are starving, or in a period of distress (which you probably are, given that you are on a diet, but that’s beside the point ;)). This leads to 2 outcomes: 1) your body lowering your BMR to reduce the amount of energy you need on a daily basis, which affects the 70% of calories you burn on a daily basis, and 2) hanging onto all the food you eat. 

Over a prolonged period of time, you see the scale’s progress slow. Not only that, you experience symptoms of fatigue, coldness, hair loss, mood swings, extreme hunger and more. We will discuss why this happens in the next post, so stay tune! 

According to Leanna M. Redman, PhD and instructor of human physiology at the Pennington Biomedical Research Center in Baton Rouge, La. Redman: “In some people, the metabolic rate [how fast the body burns calories] is only slightly reduced to make up the shortfall in energy difference, while in others it is far greater. It is this variability in the metabolic rate with energy restriction that causes much of the variability in weight loss between people.”

Thus, extreme diet restriction lead to different results in everyone – but the outcome remains the same: eventual weight loss plateau, frustration, and more often than not, weight yoyo-ing. 

How Much Should I Eat?

While it’s difficult, or even impossible to know how much calories one require due to the complexity of genetic and environmental factors, you can use many frameworks as a guideline. Using BMR and TDEE calculators is a start; then find out how much calories you burn on a daily basis through physical activity. Even if you do not exercise, daily activites such as commuting, doing work, cleaning the house all add up. 

Here’s a list of calories that different exercises burn: 

Weight Loss

Eating too little is just as unhealthy as eating too much because your body is not getting the nutrients it needs. Just as we covered in the previous post about the different vitamins and why we need them – not all essential vitamins and minerals are produced in sufficient quantities by our body. Thus, eating the right food in sufficient quantities is essential to staying healthy.     

In our next post, we discuss about the effects of undereating. Undereating typically occurs over a prolonged period of time and while we may become used to these symptoms and think nothing of it: these warning signs are signals your body is sending to please! Just give me more food!