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Long-term fasting influences the excretion of heavy metals in urine and hair in humans

Claudia Prahtel - 05/10/2021 - 0 comments

Überlingen, 30.09.2021 — A study carried out at Buchinger Wilhelmi Clinic in Überlingen showed that urinary concentrations of arsenic and nickel decreased significantly in 109 subjects after 10 days of fasting. In addition, a reduction in lead concentration was determined in hair ten weeks after fasting.

Heavy metals and pesticides found in food are a serious public health concern. Increasing environmental pollution from the industrial use of toxic substances leads to their bioaccumulation in the food chain. This can cause various diseases such as cancer, neurological and cardiovascular diseases, or infertility when human populations are exposed to these toxic chemicals.

Human exposure to toxic heavy metals and pesticides is rarely monitored. As one of the first studies in this field, exposure to arsenic, chromium, cobalt, lead, nickel and mercury was measured before and after 10 days of fasting.

Buchinger Wilhelmi, Fasten, Heilfasten, Fasting, Health, Integrative Medicine, excretion of heavy metals, publication, scientific study, Dr Françoise Wilhelmi de Toledo, scientific department


Arsenic levels in urine decreased by 72 % and nickel by 15 % during this period. Lead was undetectable after fasting and mercury levels remained unchanged. Only traces of chromium and cobalt could be detected before fasting. In addition, glyphosate, a component of the pesticide Roundup, was detected in nine subjects before fasting but was no longer present after fasting.

Furthermore, an analysis of hair to monitor the accumulation of pollutants in 22 subjects showed that lead levels decreased by 30 % during fasting.

Symptoms such as fatigue, sleep disturbances, headaches, hunger and body discomfort declined significantly after 10 days of fasting.

Furthermore, four weeks after fasting, study participants consumed more organic food and smoked less.



Overall, the new study shows that the environmental pollutants load decreased as a result of long-term fasting, and that participation in the Buchinger Wilhelmi fasting programme led to the adoption of a more healthy lifestyle.



Franziska Grundler, Gilles-Éric Séralini, Robin Mesnage, Vincent Peynet, Françoise Wilhelmi de Toledo, “Excretion of heavy metals and glyphosate in urine and hair before and after long-term fasting in humans”, Frontiers in Nutrition, 2021
DOI: 10.3389/fnut.2021.708069



Dr. Françoise Wilhelmi de Toledo