This 2025 opinion paper compared nine broccoli sprouts supplements for dogs:

“Broccoli sprouts are key elements of 9 dietary supplements for dogs. Feeding directions of 6 products correspond with consumption of dry food containing 0.5 to 29 g dried broccoli sprouts/kg. Seven supplements claim to supply sulforaphane and to possess anti-inflammatory and/or anti-cancer effects.

Directions for use of a sulforaphane-producing supplement read as follows: ‘One chewable tablet daily for dogs of all sizes, six months and older. Tablets should be given on an empty stomach at least two hours after a meal or one hour before a meal.’

There was no information found on feeding studies in dogs, addressing the impact of broccoli sprouts on health. In mice, dietary, whole-broccoli sprouts counteracted development of mammary and prostate cancer. Weights of dried broccoli sprouts in these mouse studies were 150 and 260 g/kg dry food, much higher levels than equivalents of feeding instructions for dog supplements. Species contrast and high dose blunt extrapolation of results to dogs.

The Veterinary Clinical Trials Registry of the American Veterinary Medical Association has announced that recruiting has finished for a study entitled “Sulforaphane supplementation in canine lymphoma and evaluation of epigenetic proteomic profiles”. https://veterinaryclinicaltrials.org/study/VCT17004227

https://www.researchgate.net/publication/393656647_Beynen_AC_2025_Broccoli_sprouts_in_dog_nutrition “Beynen AC, 2025. Broccoli sprouts in dog nutrition” (registration required)

The author’s use of ResearchGate is mainly to publish opinion pieces on pet animal nutrition. This doesn’t require high fees of regular journals, but also bypasses peer review.

I appreciate comparisons to rodent studies, which often intentionally overdose, and so have no relevance to humans and other mammals. His 2025 pet nutrition papers include broccoli, glyphosphate, zinc, copper, and PFAS subjects.