Comments to my realist review on ketogenic diets for cancer patients

Recently, I had the honor to correspond with Dr. Prasanta Bandyopadhyay about my realist review of ketogenic diets (KDs) for cancer patients (Beneficial effects of KDs for cancer patients (Klement 2017)). Dr. Bandyopadhyay is a professor of Philosophy in the Department of History, Philosophy, and Religious Studies at Montana State University, USA (check out his homepage here). Together with Gordon Brittan Jr. and Mark L. Taper he has written one of the most inspiring books I have recently read: Belief, Evidence and Uncertainty – Problems of Epistemic Inference. In my review, I had taken the concepts of evidence and confirmation developed in this book to summarize the available evidence for any putative anti-tumor effects of KDs in cancer patients and whether we should believe that such effects are “real” (in the sense of occurring in real world settings). Continue reading

Science is able to correct itself (in contrast to the media)

Science is a human endeavor and as such prone to errors. Therefore the peer review process, which is the check of scientific methods and results by scientific peers prior to or after their publication, plays an important role in scientific knowledge generation. Most journals still apply the pre-publication review principle, meaning that a paper only gets published after careful checking and acceptance by one or more reviewers. Continue reading

It’s the sugar stupid!

Observations that caloric restriction, i.e. a reduction in total energy intake from what would usually be consumed (called ad libitum intake), retards tumor growth in experimental animals have been published as early as 1909 by C. Moreschi [1]. In recent years, calorie restriction has been more systematically investigated, usually as a 20-40% proportional reduction of energy intake from ad libitum feeding. It has been found that it not only retards tumor growth but could also sensitize tumor cells to pro-oxidative therapies such as ionizing radiation and chemotherapeutics. The big question is through which mechanism(s)? Continue reading

Ein paar Gedanken zum Fasten

Ich kann es nicht glauben, aber kaum ein Tag vorbei und schon wieder ein neuer Blog-Post! Der Grund ist eine einfache Frage, die mir eine Arbeitskollegin heute stellte. Ich hatte die letzten drei Tage meine jährliche „Fastenkur“ gemacht, in der ich nur Wasser und Tee zu mir nahm. Es geht mir dabei vor allem um zwei Dinge: (i) schnelles Erreichen einer Ketose und Aktivierung von Autophagie, der zellulären „Müllabfuhr“ [1]; (ii) Testen der Willensstärke (Fasten fällt mir als Genussesser extrem schwer). Drei Tage betrachte ich als Maximum, da ich nicht zu viel Muskelmasse verlieren will. Die klassischen Komponenten des Heilfastens wie Abführen, Gemüsesäfte, starke körperliche Schonung lasse ich weg, versuche aber die Tage bewusster, aufmerksamer und spiritueller als sonst zu verbringen. So  marschierte ich am 3. Tag bei einer 17 km  langen Wallfahrt vom fränkischen Dettelbach nach Wipfeld mit, was zwar aufgrund des Fastens körperlich fordernd, aber sehr meditativ war. Continue reading

Die Paleo Convention 2016

Zwar ist die Paleo-Convention in Berlin, das größte Paleo-Event Europas, jetzt auch schon wieder über einen Monat her. Da das aber nichts ist im Vergleich zu der Zeit seit meinem letzten Blog-Beitrag, dachte ich mir: eine gute Gelegenheit mal wieder einen solchen zu schreiben. Continue reading

Calories, Carbs and Cancer

More than 125 years ago, Vienna medical student Ernst Freund noticed a strange phenomenon in some of his patients. Similar to diabetics, those with cancer had an “abnormal sugar content” in their blood that disappeared after surgical removal of the tumor. Some decades later, as a professor, he and others showed that compared to normal cells, cancer cells have a particularly sweet tooth in the sense that they would take up large amounts of glucose from culture medium which would stimulate their rapid growth. The most famous experiments were conducted by Otto Warburg and his colleagues in the 1920s at the Kaiser-Wilhelm Institute for Biology in Berlin. Warburg, a German biochemist and later Nobel laureate, had shown that tumor cells distinguish themselves from almost all normal cells through their preference to ferment glucose to lactate in a process known as glycolysis (1, 2). Continue reading