A message shared on social media in Nigeria advises people who donate blood to drink tomato paste and Coca-Cola as an "emergency blood tonic".
It says: "The mixture of tomato paste and Coca-Cola (or sometimes, tomato paste and malt) is an emergency blood tonic given to people who have just donated blood, lost a high amount of blood and people that experience dizziness."
The message was also shared on Africa Check's Nigeria WhatsApp group, which helps us keep track of false health information circulating in the country.
Students who 'sell their blood'
The message came from from a 2016 blog by Health Rapport Naija, which said the mixture was used by students at Nigeria's Kwara State Polytechnic. Its headline called the combination "The Fastest Working Blood Tonic".
"A good number of students... who sell their blood in blood banks to fend for themselves sell blood at least once in a week, and when they were asked how they manage to replenish their blood within a short period, they said 'it was the mixture of one bottle of coke (or malt) and one tin tomato paste (the smallest size).'"
But the blog added a disclaimer: "This post should not be considered as an expert advice. Consult your nutritionist before embarking on the usage of Tin Tomato paste plus milk or malt or coca cola for blood tonic."
There are three types of blood donor, according to the World Health Organization. These are family replacement donors, paid commercial or professional donors and voluntary, unpaid donors.
Combination has 'no medical basis'
Akanmu Sulaimon, a professor of haematology and blood transfusion at the University of Lagos College of Medicine, said the mixture wasn't a blood tonic.
"It sounds funny to me. I have never heard of this combination. It is not in the pages of my text book. I haven't heard colleagues make such a claim. It is definitely not an emergency blood tonic. It doesn't make sense in the first place."
Dr Madu Anazoezo of the department of haematology and immunology at the University of Nigeria also hadn't heard of it.
"There hasn't been any study confirming that the combination is an emergency blood tonic," he said.
Dr Angela Ogechukwu, a hematologist at the University of Nigeria, agreed that the combination had no known medical basis.
She advised blood donors against it as there is "no proven study" that it worked.
WHO and UN advice to blood donors
If a donor feels dizzy, they are advised to sit or lie down immediately, preferably with their feet raised, until it passes.
Kaia Engesveen, a technical officer at the UN agency's department of nutrition for health and development told Africa Check that the global health body "certainly has no recommendation on drinking Coca-Cola".
"Both ketchup (tomato paste?) and Coca-Cola have high levels of sugars, which would be against the WHO guidelines on sugars intake." - Motunrayo Joel (07/05/19)