How reliable is calorie information on food?

If in 100 grams of Spaghetti 359 kilo calories are, how much I should eat if my daily requirement is 2000 calories, and today I already ate 1395 calories?

Addition, subtraction, morning, noon, evening: counting calories is a tedious decline method. Each Portion is weighed, every Snack meticulously documented: an immense expense, to consent and agree to the the Slimming are not only willing, because they trust the method and the Nähwertangaben on the food. But how this information come into existence at all?

1. What exactly are calories?

Calories are an obsolete, physical unit of measure for energy. Today, one uses the term mostly to quantify the energy content of foods. This is actually not calories, but kilocalories (kcal). A Kilocalorie (kcal) equals 1000 calories. Strictly speaking, the name “calorie” is so wrong.

Energy the human body can gain share from three Food components: carbohydrates, fats and protein:

  • Fats provide about 9 kilocalories per gram.
  • Carbohydrates provide approximately 4 kilocalories per gram.
  • Proteins provide about 4 kilo calories per gram.

The calorie content of a food is, accordingly, dependent on which shares from which nutrients and how many unusable materials are included. No energy, the body can, for example, of water and salt gain, ballast substances are for the body only in small part to recycle. They provide approximately 2 kcal per gram.

By the way: A kilo-calorie is officially defined as the amount of energy needed to heat a Liter of water by one degree Celsius to heat up. In fact, converts of the body the energy from food into heat energy to. Therefore, one also speaks of a “burn calories” and “calorific value“.

2. How do I determine the calorie content of food?

According to the food information regulation (FIR) has a food manufacturer’s three ways to determine the energy content of a product:

The most common practice among the manufacturers is the calculation. The big companies have their own laboratories, in which the nutrient content of their products to analyze.

3. Who makes sure that the company not write any wrong calorie information on your products?

In all provinces there are Offices, which monitor the safety of the food. The Food inspectors to check not only whether or not the products are free from impurities and pollutants, but also whether the nutrients in the correct Form, and the values of votes. These are samples of the foods and drinks analyzed in the laboratory.

4. How meaningful the calorie information?

At the calorie information on the packaging are average values. The actual calorie content of the food, however, is not always the same, but natural variability. For example, the sugar content of fruits also depends on where they are grown, how the weather was and harvested at which point in time they were.

In addition, the body can not the entire calorie content of a food use. About 5 to 10 percent of the calories you take, separates the bowel from.

Of the food specified energy content, therefore, serves only as a guide. How this energy is then converted to the individual people, is depends on many individual factors.

The exact amount of energy that a person from food can win, depends, for example, of the intestinal flora , so the bacteria in the gut of a human being. For example, some types of bacteria are particularly good at it, to make fiber for the body to use. Who many of these bacteria carries, is a so-called good food recyclers, so more calories on food than people whose intestines mainly from other species of bacteria populated.

By the way: Earlier it was thought that the body fiber not utilize it. In the meantime, we know that bacteria in the colon fiber part remove can. The bacteria that decompose to short-chain fatty acids. Thus, ballast substances provide the body with a little energy.

5. Why have levels of the same food by different manufacturers sometimes have different Calories?

244 kilo calories are in 100 grams of strawberry jam from Rewe. About 20 calories more than the Schwartau-product and at least 70 more calories than the strawberry spread made by Zentis. All three products are made from strawberries, gelling agent and sugar. How can there be so strong deviations?

In the case of jam, it is often to the quantitative composition, especially the proportion of fruit The higher the fruit content and the lower the Sugar content, the less calories the jam. Because fruits are also calorie-apart from the fruit sugar-free or -poor components such as water and fiber.

In the case of fruit and vegetables, or food that it manufactured, often plays also the variety used in a role. Elstar-Apples, for example, are clearly calorie-rich than Gala Apples.

6. What are the percentages?

On some packaging you can find, in addition to the nutritional information also type in percentage values. On a 50-gram chocolate bar by 12%, for example, “” on frozen pizza “is 40%”. Aha, with the specified Portion of this food covers 12 and 40 percent of its daily calorie needs … or?

The specified percentage value refers to the average adult woman’s recommended daily intake, to be more precise: on the Association of the European food industry the recommended daily intake. This is 2000 kilo calories and is the value only of limited use as a guideline.

Because the actual calorie requirement of an adult depends on many factors, including the size, the weight, the muscle mass and exercise habits. For example, the German nutrition society (DGE) recommends …

  • older women, in everyday life, hardly move, a daily calorie intake of 1700 calories and
  • young men, the lot of sports or physical hard work, a daily intake of up to 3400 calories.

The significant difference shows: the percent of information is basically have no hope. It is therefore safer to determine your own calorie needs and then calculate whether the chocolate bar is still in the frame or not.

For More Information

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Online information of the German Federal centre for nutrition (BZfE): (retrieval date: 12.11.2019)

Online information of the German society for nutrition: (retrieval date: 12.11.2019)

Online information the Max Rubner-Institut (MRI), Federal research Institute for nutrition and food: (retrieval date: 12.11.2019)

Online information of the lower Saxony state office for consumer protection and food safety (LAVES): (retrieval date: 12.11.2019)

Labelling of foodstuffs. Online information of the consumer: (status: 22.7.2019)

E-mail correspondence with Bernd Hartmann, a scientist at the Max Rubner-Institute (MRI) at 9. and 10.8.2018

E-mail correspondence with Michaela Bürgelt, press officer of the German Federal Ministry for food and agriculture (BMEL) on 9. and 10.8.2018

E-mail correspondence with press officers of the companies Danone, Nestlé and Coca-Cola on 9.8.2018

Phone call with a food chemist Dr. Andreas Daxenberger from the testing company, Tüv Süd, take the 9.8.2018

What are calories? Online information of the Institute for quality and efficiency in healthcare (IQWiG): (status: 10.1.2018)

Biesalski, C.: Nutritional Medicine. Thieme, Stuttgart, 2017

Movement and energy metabolism. Online information of the public health portal of Austria: (status: 21.8.2017)

*The article “How reliable are the calorie information on food?” is published by Onmeda. Contact with the executives here.