I have no idea what are they up to with stupid posts about 'grapes' , 'dry fruits' and health benefits of sleeping longer, but it gets annoying.
I think they try to pretend they are 'real' users, establish a number of posts on the board and then start spamming.
To fight this disease we will start to moderate all new members. If this fails, we will start to moderate the initial 3-5 posts, before full membership is assigned.
An inconvenience, but we need to keep the board clean.

I also changed the settings for 'Signatures'. Only members with 3 or more posts will be allow to use them. I don't think it will impact anyone except the spammers who register only for the purpose of having the 'Signature' polluted with spam and displayed on the user profile.

I also found, removed messages and banned two user accounts used to advertise a bjj product on the forum. The two 'undercover agents' would pose as regular users of the product, describing its benefits. This 'creative' advertising is especially dangerous because we do rely on each other opinion when evaluating products.