The familiar Halloween pumpkin is a member of the squash family, native to North and Central America. The seeds of the pumpkin were used medicinally in Native American medicine, primarily for the treatment of kidney, bladder, and digestive problems. From 1863 to 1936, the United States Pharmacopoeia listed pumpkin seeds as a treatment for intestinal parasites.

Pumpkin seed oil has become popular today as a treatment for prostate enlargement ( benign prostatic hyperplasia, or BPH), and it was approved for this use in 1985 by Germany’s Commission E. However, there is no meaningful evidence that pumpkin seed is helpful for this condition. Onlydouble-blind, placebo-controlled studies can prove a treatment effective, and none have been reported for pumpkin seed oil alone. (For information on why this type of study is essential, see Why Does This Database Rely on Double-blind Studies?) However, two such studies evaluated a combination product containing pumpkin seed oil and the herbsaw palmetto.1,2

These studies did suggest benefit with the combination product, but since saw palmetto is thought to be effective for BPH, it is not clear whether pumpkin seed oil made any additional contribution.

The only reported study on pumpkin seed oil alone lacked a placebogroup, and for this reason its results prove little.3 (BPH is a condition that responds greatly to the power of suggestion, so it could have been assumed even before conducting this trial that people given pumpkin seed oil would show improvement.)

In highly preliminary research, pumpkin seed or its constituent curcurbitin has shown some activity against intestinal parasites.4,7

These studies, however, can only be regarded as highly preliminary investigations of a traditional use; they were not designed in such a way that they could prove effectiveness.

Two studies performed in Thailand hint that pumpkin seed snacks might help prevent kidney stonesamong children at high risk for developing them.8,9 However, this research only looked at chemical changes in the urine suggestive of a possible preventive effect, not actual reduction of stones. Furthermore, the design of the studies did not reach modern standards.