Dietary guidelines from groups as diverse as the Department of Agriculture to the World Health Organization urge all of us to eat less red meat — much less.

But the authors of four new studies, published on Wednesday in the Annals of Internal Medicine, report there is no compelling evidence that reducing consumption of red or processed meats will be beneficial to an individual.

A furious backlash is already unfolding. Here are five takeaways from the debate.

Nutrition studies often do not meet the most rigorous scientific standards.

The majority of nutrition studies are observational — in the case of red meat, they asked if meat-eaters were less healthy, and if those who ate more were also less healthy than those who ate less.

But it’s extremely difficult to know what someone is eating; many study participants struggle to remember and accurately report their diets. And meat-eaters may differ from those who don’t eat meat, or eat less, in a variety of ways that also influence health.