Only if you assume that all studies are valid and accurate. And even then you are drawing the wrong conclusion -- if everything is "neutral" then that means that all the positive studies are wrong and all the negative studies are correct. (You seem to have erroneously assumed that a negative study means that something is bad for you.)

Also, the very claim that there are positive and negative studies for everything is handwavy nonsense. There might 100 studies, all of which agree except for one outlier ... what does that "suggest" to you?