I use lead free solder, in my small bedroom, with basically no ventilation. I did some research and apparently the flux in lead free solder is really unhealthy.
I find that extractor fans are always too weak, what works best is what @PixelatedPolyeurthan showed – having a fan to just blow it away from you, and afterwards have a window open / extractor running.
(Wish I knew that you need this stuff when I was a kid and soldering all day at my electronics club)
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I use a fume extractor that sits behind my work piece… it visibly pulls all smoke through the carbon filter. The smell is virtually eliminated and my nose (and eyes) can attest to the difference. Just find one that has a powerful fan… it won’t exactly be silent. 
Ventilation might not be important at first but everyone reacts to the gases differently. It’s like epoxy fumes, one day you might realize a single breath with destroy you for the day. People become hypersensitive to soldering fumes over time, so I would suggest always ventilating so you never end up hypersensitive to it and have other issues. And yeah as mentioned it’s mostly the flux fumes that are the problem, even running leaded solder you’d have to have the tip very high to offgass lead and youd see the spattering.
A box fan and 20x20 MERV13 Filter. Does okay, no decent layer of carbon though so it still lets some blow through, but its a lot better than nothing, and definitely better than just a fan. The filter is now all yellow and brown from the fumes so it must be catching something.
Having a separate one for inside your house is also pretty nice, especially during pollen seasons. Ill wake up without any allergies, but after being outside for a bit, they come right back. At least I can sleep in peace. Before having it, allergies were an issue. Also since it is a box fan, its flow rate is crazy high. Its not like those overpriced $100 filters that put out 1/10th the volume,
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So I have a similar set up at work with a box fan and a HEPA filter on the backside. It works really well. We also use IQAir purifiers with carbon filtration, but the bulk of filtration with the box fan…
One thing I have been doing recently is using Filti fabric on the box fan to enhance the filtration. Check out their website if your interested, they use nanofiber technology for physical filtration rather than electrostatic.
Because it is physical, their filters can be washed and reused (no worry of charge loss), so it is a bit cheaper in the long run.
I wouldn’t snack on the solder nor would I lick my fingers afterwards. But other than that the lead isn’t the dangerous part.
Solder outside if your soldering for longer periods of time, or use some kind of fans to move the fumes away from you and keep the room ventilated as much as you can.
Im glad i solder 80-20 without flux then 
Dont have good ventilation, but i dont solder very much either.