The vegetable cassava cures cancer, a Facebook post shared in Nigeria in November 2019 claims.
It reads: "I ate 10 grams of cassava three times a day. After eating cassava for one month, my doctor checked my bladder for cancer. He was surprised because my bladder was completely clean and normal."
Cassava is a root vegetable - like potatoes and carrots - that's grown by smallholder farmers in more than 100 countries, according to the UN Food and Agriculture Organisation. The FAO describes it as the "food of the poor" that "responds to the priorities of developing countries".
And it's a good source of carbohydrates, calcium, essential minerals and vitamins B and C.
"As long as I kept eating cassava, I felt very fit and very healthy," the post reads. "Since then, I only ate cassava and did not continue other cancer medications."
The post says cassava contains "vitamin B17". When eaten, it claims, the "vitamin" converts into an acid in the body that "kills cancer cells locally". It goes on to give more examples of cancer patients who saw a dramatic turnaround in their health after consuming cassava for weeks.
Vitamin B17 isn't a vitamin - and contains cyanide
People shouldn't "replace conventional cancer treatment with any type of alternative cancer therapy, such as laetrile", Cansa says.
"Laetrile can cause serious side effects in some people because of its cyanide content." Cyanide is a poison.
Cassava could fuel cancer
"Cassava does not cure cancer or eliminate cancer cells," he said.
"Cassava is a source of carbohydrates and can be broken down into sugar. Sugar is fuel for cancer cells. We do not advise our patients to take in excess carbohydrate.
"The claim is not scientifically proven nor medically approved." - Jennifer Ojugbeli