It may be difficult to pick just one best natural treatment for teenage acne.
But, I have done a ton of research and have picked what I feel is the best, and you can even grow it at home if you want: Aloe Vera.
Now, I know, this is usually used primarily for sunburns, but it's great for acne too.
Simply take a small amount on the tip of your finger, and rub onto problem areas.
Now, the trick is in the amount.
You don't want to have a giant glob of aloe, just enough to cover the area thinly.
It's also better to do in the morning, so that your pores have time to open up and breathe at night.
Another great trick is to use the Aloe Vera as a mild face wash once a week.
Simply put a slightly thicker amount than usual, let sit for 30 minutes, then wash off with warm water.
After it's all off, run a washcloth under warm water, wring out, then cover your face a minute or so.
This will open your pores as much as possible, and any toxins will hopefully be caught by the washcloth.
Then, do the same with cold water to close your pores and keep new toxins from getting in.
The last tip is the most important, prevention.
Don't pop your zits or pimples! This stretches the pore, making it much more likely it'll be a problem as it will be easier for toxins to get in.
It may be a little unexpected, but it's easy to come by and much cheaper than most commercial products.
That's why I personally feel that Aloe Vera is the best natural treatment for teenage acne, and that's why I still use it today.