Beyoncé Knowles and Jay Z have been accused of styling their marriage like a reality TV show.

The music power couple have been married since April 2008 and they have three-year-old daughter Blue Ivy together. Their union has been rocked by rumours over the last year, after Beyoncé's sister Solange was caught on camera attacking him in a lift. There were allegations that the rapper had been unfaithful, which have never been substantiated.

Last week a trailer for a documentary called Why Men Cheat premiered and showed US reality TV star Sincere commenting on the union, insisting the pair never look like they are into each other. He's now expanded on the remarks.

"There's a lot of pressure on them to be together, to appear happy [all the time] and to not have fights. On a reality show, they edit your life for the most drama possible," he told British magazine Heat. "But for [Beyoncé's] Instagram, it's the reverse. If you're somebody as big and famous as Beyoncé and Jay Z, you can [say], 'Alright, we 'bout to go to St Barts, there's gonna be a photo opportunity, so that's a period to be happy.'"

In the promo clip, Sincere called Beyoncé and Jay Z's marriage a "smart business move".

It's not the first time the pair have been accused of staying together for work reasons, something which was widely discussed during their On the Run Tour.

Sincere isn't good friends with the couple, although he has seen them together in public. Most recently was at a Big Sean album listening party in February, which he was happy to talk about.

"They don't show a lot of affection in public. Y'know, they just seemed to be [pause]... friendly with each other," he alleged.

This isn't the only blow that Beyoncé has suffered lately. She was recently slammed after widely promoting a big announcement she had planned on a US breakfast TV show, only to go on air and talk about her vegan diet.