Roundup Unready

A controversial study blames the active ingredient in Roundup for cancer, diabetes, and other medical ills.

June 28, 2013

Glyphosate, the active ingredient in Roundup and several other brands of herbicide, may be the culprit behind many of the so-called "diseases of civilization" that have plagued humanity since the last third of the 20th century and are escalating at alarming rates today. These diseases and conditions include gastrointestinal disorders, obesity, diabetes, heart disease, depression, autism, infertility, cancer, Alzheimer's disease, Parkinson's disease, birth defects, and more.

What Roundup is probably doing to your health

That's the conclusion of two scientists who reviewed 286 studies of the biological effects of glyphosate and published their findings in the peer-reviewed journal Entropy in April 2013. These findings are a bombshell that, if confirmed by further studies, could lead to a worldwide ban on glyphosate.


In their search of the literature, environmental scientist Anthony Samsel and Stephanie Seneff, senior research scientist at Massachusetts Institute of Technology's Computer Science and Artificial Intelligence Laboratory, found that glyphosate suppresses and inhibits cytochrome P45, a class of human enzyme known in scientific shorthand as CYP.

Inhibiting enzymes is exactly how glyphosate works as an herbicide. Enzymes are catalysts for all sorts of functions in plants, and when they are suppressed, the plants die for lack of the ability to function properly. Something of the same effect may be at work in humans who ingest glyphosate on their food.

"Glyphosate's inhibition of CYP enzymes is an overlooked component of its toxicity to mammals," Samsel and Seneff write. "CYP enzymes play crucial roles in biology, one of which is to detoxify any foreign substances not normally found in living creatures, such as pesticides, industrial chemicals, pollutants, and drugs. Thus, glyphosate enhances the damaging effects of other food-borne chemical residues and environmental toxins. The negative impact on the body is insidious, and manifests slowly over time as inflammation damages cellular systems within the body."

The authors describe how glyphosate harms three crucial bodily functions. First, it interferes with CYP enzymes. Second, it disrupts the ability of intestinal microbes to construct important amino acids that build and repair the body's cellular tissues. Third, it impairs the movement of sulfate compounds in the blood. These compounds are especially important in the growth of infants, young children, and developing fetuses. Glyphosate's enzyme inhibition acts synergistically with the other two damaging effects; that is, it produces a more serious health effect than the sum of the individual effects.

Samsel and Seneff conclude with a plea for more independent research. "Glyphosate is likely to be pervasive in our food supply," they write, "and contrary to being essentially non-toxic, it may in fact be the most biologically disruptive chemical in our environment."


What the authors have done in this review of the scientific literature on glyphosate is to connect the dots, with each dot being one of the 286 studies. Entropy, which published the article, is an online open-access journal that is willing to publish novel hypotheses regarding biochemical and biophysical phenomena. The papers in the journal are subjected to review by experts who are not beholden to industry influence. Publishing fees are paid by the authors or their institutions.

Samsel is a long-time environmental scientist, now retired, who operates an organic farm on 5 acres in New Hampshire. Seneff became interested in glyphosate through her research on autism. Their review was funded by Quanta Computers, a notebook computer and cloud computing company based in Taiwan. "We did not do any new research other than predict the likely consequences of glyphosate, given the evidence available in the papers we reviewed," Seneff says.

Of course, the study has raised the hackles of those who think glyphosate is great stuff. Skeptics have lined up to discredit the paper and its authors. But Samsel and Seneff have simply combed the literature to see what science has found out about glyphosate, and they've come to the conclusion that the chemical has extremely deleterious effects on human health. Let those who argue otherwise point out the flaws in the 286 studies the authors have pored through, rather than attacking the authors for doing good research.