The company announced in a blog post on Wednesday that it has halted sales after receiving complaints from a number of customers. People said they have fallen ill after eating the food bars, and they’ve caused them to suffer gastrointestinal problems such as nausea, vomiting, and diarrhea.

Soylent has stopped distributing the bars and is currently investigating the situation. On the company’s website, the bars are listed as “Currently Unavailable.”

Soylent’s products have been described as “meal replacements.” The company says they contain all the nutritional requirements that the average adult needs delivered in the form of vegan, nut-free, and lactose-free powders, drinks, and bars.

Soylent has not yet discovered the source of the problem with its Food Bars, but it said the problem does not seem to be affecting any of its other products. The company has urged customers who have already purchased the bars to throw them away.

Soylent could not immediately be reached for further comment.