That's the whole point though - science so far can't give much useful advice on what to eat, the topic is just too complex.

Science can give hedged explanations of what's been observed in relation to a particular nutrient, but that's a far shot from dietary advice.

What seems to end up happening is "we've observed a correlation between saturated fat consumption and heart disease" makes it out of the science world and gets turned into "avoid saturated fat at all costs" (and buy our replacement products). Then years later we realize it's a lot more complicated than that.