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.