Table of Contents
1 What does junk food do to us?
2 Junk food: What is it anyway?
Junk food vs. fast food
3 Tips for reading food labels
Ingredients Nutritional values
4 How to resist junk food
5 Super Size Me: A dangerous experiment (30 days of junk food)
6 Everything important in a nutshell

Is junk food really "garbage"? We take a look and give you the most important facts about junk food: What is junk food? What is junk food made of? How does it affect us? And how can we resist the temptation?

Junk food is on everyone's lips. Advertising and supermarkets are full of it. It has long since found its way into our heads and bellies. But what's behind it and what's in it? And what is actually the problem with it? In this article, you'll find out everything you need to know about junk food: what it is, how it works and why you should stay away from it. We provide the most important facts and useful tips on how to avoid the junk food trap.

What does junk food do to us?

The combination of high sugar and low fiber content causes our blood sugar levels to skyrocket after "eating" junk food and then plummet again. The result: cravings, tiredness and weight gain.1 Junk food also slows down our metabolism, disrupts digestion and reduces the feeling of satiety despite excessive calories.2

But it's not just the immediate effects of junk food that are negative. It also causes problems in the long term. Obesity, diabetes, increased blood pressure, constricted blood vessels and an increased risk of heart attack and stroke are some of the many negative effects of long-term junk food consumption.7 It makes you forgetful, lethargic and possibly even depressed8

What's more, junk food is deliberately designed to be highly addictive9 Sophisticated nutritional principles are used to create unnatural products that appeal to our brain's reward center and flood our senses. The combination of different, intense flavors ensures that we literally cannot eat enough. The texture, the smell, the sound of chewing - it's all carefully orchestrated in numerous tests to make us want more and more."10 In addition, food companies invest billions in marketing and advertising to anchor themselves in our minds.11 No wonder junk food is no longer just on the agenda in the USA.

Junk food: What is it anyway?

"Junk" means something like "garbage", "crap", "junk". "Food" means "food" or, more broadly, "nourishment". Junk food therefore means low-quality food. So the question arises: what is "inferior"? A look at nutritional science provides clarity: junk food refers to food and drinks that provide a high level of energy with a relatively low nutrient density. In other words: lots of "empty" calories (mainly in the form of sugar and fat), hardly any vitamins and 12

Junk food vs. fast food

Junk food is often referred to as "fast food". However, it is important to draw a clear line between these terms. "Fast food" means nothing other than "quick food" - i.e. food that is prepared quickly and easily and is readily available. The term fast food refers to the preparation time, junk food to the quality. Fast food can therefore also be healthy, while junk food can take a long time to prepare.

Here is an example: an apple can be described as fast food because it can be eaten quickly and at any time, even on the go. Nevertheless, from a nutritional point of view, it is not "garbage" because it provides our body with valuable vitamins, 16

It also contains a large number of chemical colorings and preservatives as well as flavor enhancers. Some of these have a negative effect on key aspects such as metabolism, organ function, 17 blood values18 or memory performance19. The risk of cardiovascular disease can also be increased by excessive consumption of additives.20

Too little...

What is missing in junk food, on the other hand, is what keeps us full and healthy: Fiber, high-quality protein, vitamins, minerals and secondary plant substances. In most cases, only traces of these are contained, if at all. So if you eat mainly junk food, you run the risk of developing deficiency symptoms in addition to the risks already mentioned. At the latest now it's clear: stay away from junk food! But you have to recognize it first. 

Tips for reading food labels

Ingredients

Keep your eyes open for artificial additives that are labeled either as E-numbers or based on their function (e.g. "raising agent", "acidulant", ...)...21 You should also keep an eye out for sugar. It is hidden in almost all processed foods, often under names that sound "healthy."22 "Grape sweetener", "fruit extract" or "apple syrup" are just a few examples. Sugar has many names, but its harmful effects on health remain the same.

Nutritional values

The sugar content of products can be seen more clearly in the nutritional value table. There you can see how many grams of sugar per 100 grams and per portion are contained in the respective food under the carbohydrate content. Also note that the portion sizes given do not necessarily correspond to the amount you actually eat. As a guide: The German Diabetes Society recommends consuming a maximum of 50 grams of sugar per day.23 This value is already exceeded with a quarter of a liter of industrially produced lemonade.

Another indicator for assessing the nutritional quality of a food is its fiber content. In this case, more is more, because fiber keeps us full and stimulates digestion.24 Ideally, a food should contain more fiber than sugar. Adults should consume at least 30 grams of these indigestible carbohydrates in their diet every day.25

You should also pay attention to the proportion of saturated fatty acids in a product. This should be as low as possible, as saturated fatty acids are associated with cardiovascular disease, diabetes and obesity.26 According to the WHO, saturated fatty acids should make up less than 10% of the daily energy intake.27 That is about 22 grams for an adult.

Junk food is also characterized by an enormously high salt content. Surprisingly, this is also the case with sweet products such as cornflakes or ready-made cakes. The WHO recommends consuming no more than 5 grams of salt per day.28

A final key criterion for recognizing junk food is its high calorie density.29 This can also be easily read off the label, as it depends on the calories per 100 grams. You should be careful with products that have over 400 kcal per 100 grams - especially if these calories come mainly from sugar and fat.

How to resist junk food

The first key step is to become aware of what junk food is and what it does to us. With this knowledge, we can deal better with cravings for junk food. You can then understand the mechanisms that take place in our body and brain. This allows you to make a conscious decision as to whether you want to indulge in it as an exception or whether you would be better off with something else. 

A helpful strategy when you are overcome by cravings: the 10-minute rule. Before reacting rashly to an impulse that has nothing to do with what your body really needs, wait 10 minutes. Junk food cravings are often very short-lived and disappear as quickly as they appeared. Sometimes they are triggered by an intense emotion that fades after a few minutes. Sometimes it is also misinterpreted thirst that makes us reach for chips & co. Tiredness and stress can also play a role. Waiting 10 minutes and taking a moment to think about whether the craving can be conquered without junk food can make a big difference.30 After all, our body is not a garbage dump. So junk food is definitely not the right "fuel" in the long run.

Super Size Me: A dangerous experiment (30 days of junk food)

To illustrate the devastating effects of junk food, US director and filmmaker Morgan Spurlock launched a self-experiment in 2004. For 30 days, he adopted the lifestyle of many of his fellow citizens: Three meals a day consisting exclusively of junk food and hardly any exercise (a maximum of 5,000 steps per day). In his film "Super Size Me", he shows the preparation and execution of his experiment

He also discusses the results with several doctors and nutritionists. And they are shocking: in just one month, Spurlock gained over 11 kg, which corresponds to 13% of his initial weight. His body fat percentage rose from 11% to 18%. Spurlock's cholesterol levels and blood pressure increased significantly, reaching levels that represented a demonstrable health risk in this short period of time. After 30 days of fast food, his risk of cardiovascular disease had doubled and his liver values had deteriorated massively. 

Spurlock was tired, listless and in a bad mood, which had a negative impact on his sex and social life. Furthermore, he felt an increasing urge to eat junk food over time, even though he felt bad afterwards.31 This points to the aforementioned addictive potential of such products. Nevertheless, you are not automatically at the mercy of the junk food trap.

Everything important in a nutshell

  • You can recognize junk food by its high sugar, salt and calorie content, the high proportion of saturated fatty acids and the lack of fibre.
  • A lot of salt and chemical additives can be found in junk food, which can lead to high blood pressure.
  • The term "junk food" refers to the low quality of the food, while "fast food" refers to the speed of preparation. 
  • Excessive consumption of junk food can lead to chronic fatigue, obesity, diabetes, memory problems and an increased risk of cardiovascular disease, among other things. 
  • Junk food is deliberately designed to be addictive.
  • Be aware of the composition and effects of junk food and have healthy alternatives ready when you are tempted.

As I said, we can recommend fast food, but not junk food. There's nothing wrong with grabbing a quick meal if you don't have time to cook or are on the go. But there are better options than a pizza slice or a donut from the bakery.
Meal replacement shakes, including astronaut food offers a balanced option for a quick meal. Try our drinkable meals, maybe you'll find an alternative for stressful times!

Sbalitelný obsah

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