I eat so little – Why can’t I lose weight?

Is this you? You can’t lose weight even though you’re eating very little. If it isn’t then I can almost guarantee you know someone like this! It can be the most frustrating part of a weight loss journey, turning your wheels and feeling like you are getting nowhere.

Searching the internet for an answer for this phenomenon will put you in a panic.

So many options and issues that it could, be but let’s rather put it simply. We know the rule for weight loss is to burn more calories than we take in. A concept that many of us know of but don’t fully understand and take advantage of (yet). Calories out need to be greater than calories in in order to create a deficit and therefore weight loss.

Simple, however, we often forget that this law is wrapped in:

  • Our BMR or basal metabolic rate- how much we burn at rest. Just functioning with our natural
    metabolic processes
  • Movement on a daily basis – sedentary job or active, taking many steps
  • Producing heat for life processes in the body – bigger people actually burn more calorie
  • Digestion and excretion – speaks for itself


I often hear about, “oh I didn’t lose weight this week because my hormones are out of whack”, or because “I ate too little this week and my metabolism slowed down”.

But what is the truth?

The truth is? Your calories in were still higher than what you burnt from training and from the above thermogenic
processes. Insulin resistance may mess with appetite and cravings, as may your other hormone levels affect fat to lean mass. But it will never invalidate the basic principle that you need to consume less calories than you burn to lose weight.

The difficulty in all this?

Tracking weight loss and managing it, it is difficult to measure the metabolism. In fact, the only true way to do this is by using a sealed metabolic chamber. Estimating calories can be inaccurate and even more so because our fitness trackers are not an indication for how much you actually used up in a session. If anything a fitness tracker is nice just to compare your intensity session to session and over time.

As human beings we are terrible at estimating how much we ate and how much we burned. Most of the time we are inaccurate by up to 40% and when you are really trying to lose weight, well this just says it all. When you start to take this science a little more seriously, and use portion size guides, cup measures and scales you will be shocked to discover your true calorie intake.

Take this example, how many times have you been on a diet and eaten perfectly through the week? Then you have a blow out on the weekend. Because you missed food so much and figured that one day or one meal couldn’t hurt so much? Only to find you lost nothing after that or even worse you picked up weight?! Yup this is the issue of us being back at “guestimating” (guessing and estimating calories in your meal).

You see, the rule isn’t broken, but our perception of foods calories and the amount we burn in training are.

My advice:
1- Don’t try to out exercise a bad diet
2- Get your daily steps up
3- Have a more accurate way of measuring your calorie intake
4- Drink enough water

I am not trying to promote a certain way of dieting/ losing weight. Just sharing the science, take away what you need. If you aren’t wanting to count calories or track food, just understand the process may be slower because it can be flawed. Do what feels right for you long-term

Good luck lovely

Isilda Da Costa is a personal trainer and women’s fitness specialist who, if she isn’t at the gym training, is busy researching the most up to date information for growing those muscles. She has combined her love of everything healthy by being a health coach in her own health shop in Swaziland. Follow along on @izzy.healthandfitness

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