British reports suggested that an EFSA report had warned that eating less than a teaspoon of linseed (which contains amygdalin, a naturally occurring chemical compound that can produce cyanide as it degrades) might pose a risk to small children. The EFSA report in question stated: “Taking into account all uncertainties, a risk for younger age groups cannot be excluded if ground linseed is consumed.”
But EFSA made clear its position to FoodNavigator, stressing that its stance had been overestimated.
“EFSA’s opinion does not state that consuming one third of a teaspoon of linseed leads to poisoning,” a spokesperson said. “It states that, in a worst-case scenario, one teaspoon of ground linseed could lead to reaching the acute reference dose (ARfD).” An ARfD is an estimated intake of a chemical substance in food, expressed on a bodyweight basis, that can be ingested over a short period of time, usually during one meal or one day, without posing a health risk.
“The quote used in several articles refers to an assumption made on a worst-case scenario that not only considers factors such as body weight, but also the concentration level of cyanide (CN) included in the seeds,” the spokesperson continued. “In the worst-case scenario, the highest amount of cyanide measured - a total CN level of 407 mg/kg is taken into consideration, not an average amount.”
Therefore, a child who consumes that amount in one go could but not automatically exceed the ARfD. The EFSA stressed that the ARfD is a very conservative estimation: it ensures that under that level of consumption the dose is very safe. What’s more, exceeding the ARfD doesn’t lead automatically to poisoning or even to any adverse effects.
Authorities in Sweden discourage the consumption of crushed flaxseed. The Swedish National Food Agency website says: “There is not yet enough knowledge to say how much crushed flaxseed to eat without the risk of damage to health. Therefore, our advice is not to eat crushed flaxseed.”
But EFSA pointed out that no case of poisoning by linseed had been reported. That’s not the case for the consumption of apricot kernels that can put people at risk of cyanide poisoning, which can cause nausea, headaches, insomnia, nervousness and, in extreme cases, death. For children five or more kernels appear to be toxic, according to the EFSA.
Studies, meanwhile, support the health benefits of flaxseed, suggesting it may reduce blood pressure and protect against diet-induced obesity.