Is It Dangerous To Lose Weight Too Quickly?

Are you looking for a diet to lose weight? Talk to your doctor, so they can help you choose the best diet for your needs. Losing weight too quickly with a "miracle diet" can be dangerous for your health.
Is It Dangerous To Lose Weight Too Quickly?

Last update: 28 April, 2020

In general, when you decide to start a diet to lose weight you want to see results as quickly as possible. However, did you know that it can be dangerous to lose weight too quickly?

Losing those extra pounds can take time and effort, and that’s totally normal! The healthy way to achieve your ideal weight is to do it little by little, because, if you don’t, you can damage your body. We’ll tell you how in this article.

Is it risky to lose weight too quickly?


A woman measuring her stomach.
Losing weight quickly can be bad for your health.

Starting a restrictive diet to lose weight is normally complicated, especially if you enjoy food. Getting on the scale and seeing that the needle is at the same place as the day before can be frustrating. However, you should be patient and follow your doctor’s advice.

Miracle diets where you lose several pounds a week can be really risky for your body. Because of this, they aren’t recommended by health professionals.

You’re probably asking yourself, how quickly is too quickly? Generally, health professionals consider a weight loss of between 1-2 pounds weekly to be healthy, more than 2 pounds would be considered “very quickly”.

It’s worth clarifying that, if you suffer from liquid retention, you’ll likely lose more than 2 pounds per week during the first few weeks of your new diet.

Effects on the body

The body needs a certain amount of calories daily to fulfill its different functions. Excess weight is caused when calorie intake is higher than these necessities, and to lose weight healthily, ideally you should reduce your intake progressively while also increasing physical activity.

Caloric needs vary from person to person depending on your sex, age, and level of physical activity, among other variables. Due to this, we recommend that instead of adopting a miracle diet, you go to your nutritionist, so they can evaluate your health and design a personalized diet based on your physical condition.

Now then, what happens when you decide to decrease your food intake through an extremely restrictive diet? Losing weight too quickly carries risks like:

1. Muscle loss

Muscle loss, risk when you lose weight too quickly.
When you follow an extremely restrictive diet, your body loses its glucose reserves and starts consuming muscle tissue.

One of the biggest mistakes people make when they turn to miracle diets is that they want to lose weight without understanding that what’s really important is reducing body fat. That is, losing weight is not the same thing as losing fat.

Muscular catabolism is caused when the body, needing energy and not getting food, starts to feed off its own tissues, including muscle tissue.

In 2016, a study evaluated a group of people with a very low-calorie diet for 5 weeks and a control group with a low-calorie diet for 12 weeks (500 calories versus 1500 calories daily). At the end, the number of pounds lost was similar, but the first group lost six times as much muscle mass. 

2. It slows your metabolism

Some research has found that when you lose weight too quickly, it can cause your metabolism to slow down, which means you burn fewer calories. In fact, it’s been proven that the daily amount of calories you burn can reduce to about 23% fewer than normal.

3. It causes nutritional deficiencies

Nutritional deficiency.
By reducing your intake of essential nutrients, there’s a high risk of deficiency diseases.

A very low-calorie diet can cause nutritional deficiencies, when you don’t consume all the vitamins and minerals your body needs to work well. Nutritional deficiencies can cause:

4. Gallstones

Every time you eat, your gallbladder releases gastric juices that help to break down the food so that it can be digested. Some studies have shown that when you eat a smaller amount of food, some bile that isn’t released could form gallstones

5. Other problems

We’ve already mentioned some of the biggest risks associated with losing weight too quickly. Beyond these serious health risks, you can experience other problems like:

  • Dizziness
  • Feeling cold
  • Irritability
  • Muscle cramps
  • Constipation
  • Diarrhea

If you want to lose weight, you should avoid doing it too quickly. Don’t start a weight-loss diet without medical supervision. Remember that before changing your eating habits, it’s always wise to see a nutritionist first.

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