They quote some quack sites as their sources of information, not any actual studies and I burst out laughing at 'Lowers your blood pressure' as a negative side effect. However, I have read there have been a couple of instances of them getting lodged in people's oesophaguses because they're so effective at absorbing water and swelling up, but soaking them first gets rid of that risk. I tried soaking them in almond milk a couple of times, but can't stop them solidifying in the bottom of the bowl, If anyone has a solution for this, I'd be delighted to hear it.