Browse evidence-based analysis of health-related claims and assertions
Oxalates are plant-derived compounds that can bind with calcium in the kidneys to form calcium oxalate kidney stones.
Assertion
The hormetic dose-response curve for plant-derived phytochemicals in humans is undefined, with no established thresholds for beneficial versus harmful effects.
Selective breeding of plants creates novel genetic combinations but does not eliminate their inherent production of defensive phytochemicals.
Animals do not produce phytochemical-like defensive toxins because their primary defense mechanisms are physical (e.g., speed, strength, biting), not chemical.
Wild, unmodified plant species are generally unpalatable to humans due to high concentrations of defensive compounds, limiting their consumption without processing or selective breeding.
The bitter taste of many plant foods is a direct result of the presence of defensive phytochemicals that deter herbivory.
Plants produce a variety of natural chemical compounds as defensive mechanisms against herbivores and pathogens.
Modern broccoli takes almost two months less to grow than sprouting broccoli, which means farmers can harvest it quicker and plant more crops per year.
Quantitative
Purple cauliflower has more perfectly uniform florets than modern broccoli — a trait breeders might want to copy into broccoli to make it look better.
The DNA of modern broccoli has more A and T building blocks than older types — a pattern also seen in corn and soybeans, likely from long-term breeding.
Sprouting broccoli has way more unique genetic variants than store-bought broccoli, making it a treasure trove for breeders trying to add new traits.
Modern broccoli’s genes stay linked together over much longer stretches of DNA than in purple cauliflower, meaning breeders have been mating very similar plants for generations.
Today’s broccoli heads are much tighter and more uniform in shape than older varieties, which makes them look better and sell better in stores.
Two very old broccoli varieties from the 1800s and 1950s are the genetic ancestors of almost all modern broccoli hybrids sold today.
Descriptive
A specific spot on broccoli’s 9th chromosome — which controls when it flowers and how it handles heat — has been heavily selected by breeders, making it a key target for improvement.
Today’s broccoli varieties can handle hotter weather better than older ones, which helps farmers grow them in more places and during warmer seasons.
The old-fashioned broccoli types from southern Italy are not closely related to the sprouting or purple cauliflower types — they evolved separately, even though they’re all the same species.
Scientists found 53 spots in the broccoli genome where genetic variation has been wiped out — likely because breeders picked plants with certain traits so often that other versions disappeared.
Modern broccoli puts way more of its energy into the part we eat — the head — compared to older types, which wasted more energy on leaves and stems.
Modern broccoli has much smaller individual florets than older varieties, which makes the head look tighter and more uniform — something breeders have been selecting for.
Over the last 130 years, the size of broccoli heads has gotten bigger by almost a gram each year, because breeders have been selecting for larger heads.
The broccoli we buy in stores today has much less genetic variety than the old-fashioned types grown in southern Italy, meaning farmers have lost a lot of natural diversity by breeding for uniformity.
People who regularly eat berries, drink tea, or eat dark chocolate have lower rates of heart disease and stroke, and live longer.
Correlational
Phytate in beans and whole grains may protect your colon by binding excess iron that can cause cell damage, and may even help people with diabetes avoid complications.
Mechanistic