The year 2026 marks the 80th anniversary of the discovery leading to the development of the microwave oven. In 1946, the US engineer Percy Spencer noticed, whilst experimenting with a magnetron*, that microwaves can heat food. This observation later evolved into the first microwave oven, which became known as the ‘Radarange’.
Today, microwave ovens are among the most widely used kitchen appliances worldwide. According to estimates, over a billion households use this technology. In Europe, for example, around 80 to 90 per cent of households own such a device. In emerging economies, too, their popularity is steadily increasing. The reasons are obvious: microwaves are fast, convenient, energy-efficient and easy to use, and thus meet the demands of an increasingly hectic daily life. The focus of modern kitchen appliances is generally on efficiency and saving time. Gentle food preparation and concerns about long-term health effects tend to take a back seat.
However, our bodies depend on being able to optimally utilise the nutrients we consume. Through metabolism, food, medication and other substances are broken down into their constituent parts so that the cells can carry out their functions relating to the building, regeneration and detoxification of the body.
Technical electromagnetic fields (EMFs), such as those used in microwave ovens for heating food, can trigger numerous reactions in the organism. One of these is the increased formation of free radicals. An excess of free radicals impairs the body’s own defence mechanisms, leading to oxidative stress. This can attack cells and damage important structures such as proteins and even genetic material (DNA). Oxidative stress is therefore considered a major risk factor for cardiovascular disease, cancer and other chronic illnesses.
Heating food in the microwave can also lead to the loss of important antioxidants and other valuable nutrients. Furthermore, if food is reheated in plastic containers or packaging, undesirable substances from the material can leach into the food, which further reduces the quality of the food consumed.
Heat is generated in a microwave oven through the extremely rapid excitation of water molecules. This polarity reversal is the cause of profound changes in the structure of food. This not only leads to the aforementioned reduction in the nutritional content of food, but also alters its chemical and physical properties. Such changes are perceived by the body as a strain or a threat and can trigger corresponding defence reactions.
Studies carried out as early as the 1980s by the Swiss biologist Dr Hans-Ulrich Hertel show that, following the consumption of microwave-cooked food, changes in various blood parameters can occur in the human body, indicating significant strain on the organism. Among other things, an increase in leukocytes (white blood cells), reduced oxygen uptake and an increase in the haematocrit level were observed. These changes suggest that consuming food prepared in a microwave oven is harmful to health and may, in the long term, increase the risk of serious illnesses.
It is therefore advisable to prepare food in the traditional way on the hob, in the oven or in a steamer, as these methods heat the food from the outside in and cause hardly any change to the molecular structure of the food.
You can find more information on this topic in our newly published folder ‘Microwaves and Cancer: Why does food from the microwave harm our bodies?’
*High-frequency generator that produces microwaves. Magnetrons were originally used in radar equipment.
