Dietary supplements containing germanium started becoming popular in the 1970s in Japan. From there it spread to other countries, where it became known as an elixir against certain diseases. Germanium is found in the Earth's crust. Plants and the human body also show traces of germanium. This element is available in plenty of plant foods such as vegetables, leguminous seeds, wheat and bran; while it is almost nonexistent in animal foods. Germanium is considered to be the prime reason why nutritional practitioners recommend taking garlic, ginseng, mushroom, and comfrey. Some organic complexes of germanium have shown the capacity to curtail the growth of tumors in animals.

A lack of germanium is associated with infection and immune disorders, but the biological role of germanium is still unclear. Germanium is not an essential element. The nutritional supplement form of germanium is known as germanium sesquioxide or Ge-132. This is a synthetic organic product found naturally. This form of germanium has been used to boost the immune system and improve body system functioning. Germanium products have been used to treat a variety of problems like arthritis, heart disease, AIDS, cataracts and cancer. People suffering from neurosis, asthma, diabetes, hypertension and hepatitis also find relief after taking germanium. It is said that germanium causes the production of interferon, which is a naturally occurring anti-cancer agent. By boosting the activity of the natural killer cells in the body, germanium helps the immune system to fight invading germs. To some extent, disease states like osteoporosis and heart disease have responded favorably to germanium therapy. Strong oxygen regulation and antioxidant activity is undertaken by germanium in the human body.

But there is no scientific evidence as to the benefits of germanium. Many herbal supplements containing germanium are mixed with possibly harmful impurities/additives, rendering them dangerous. The use of germanium has been associated with various side effects, so it is dangerous to use this product without consulting a physician. Though its actual toxicity is low, the Food and Drug Administration (FDA) has reported that supplements that contain germanium present a potential hazard to humans. Therefore the FDA has banned the import of germanium. At least 31 human cases have linked prolonged intake of germanium supplements with kidney failure and even death. Interestingly, germanium found naturally in food products do not appear to be toxic.

Germanium products are available in powdered form or as capsules. The peculiarity of the structure of germanium causes it to be easily contaminated with inorganic germanium, which is more toxic. It is unclear whether the side effects associated with it are due to organic germanium or due to the supplement's interaction with inorganic germanium. In a study conducted on a small group of humans, even small levels of germanium have been found to be toxic. In many patients, their symptoms got worse, and illness was compounded by side effects. Scientists are vociferous in their warning that inorganic germanium may lead to permanent kidney damage and even death.

Germanium may also interfere with other medications and make certain symptoms worse (seizures, for instance). Very little is known about the effects of germanium on pregnant women. Therefore such women should never take germanium, unless advised by a physician. Other ill effects include weight loss, anemia, vomiting, muscle weakness, and numbness in the hands and feet. The deadly effects of the toxin builds up with time, and in the long run, symptoms get worse.