I see people take a lot of vitamin B6 for exprementing!
200 mg! it’s a lot!
I ate 2 banans before I went to sleep and had 3 lucid dreams in a night,
They contain just 1.6mg togheter!
So I think taking 2mg before sleeping is enough to LD.
Eh… perhaps it was just your mind thinking “If I eat two bananas, I will have a lucid dream !” and you had 3 
I tried the banana technique once - no result…
Well maybe…
Too much b6 is not good for your body, like everything else in too much dosage is not haha 
But that’s something you should be aware of if you’re taking b6 pills. If you’re getting it from food it’s all good.
I read somewhere that you can find b6 in milk and I tried drinking a lot before going to sleep and it helped a bit, or it was just the placebo effect.
Any b vitamin (b6 b12 etc) in and of itsself has a very small chance of toxicity. The reason behind this is that it is a water soluable vitamin. There is a mnemonic to remember the fat soluable vitamins (the dangerous ones) its KADE as in viatimins k a d and e are fat soluable therefor they can lead to toxicity easily. But remember, before taking any dosing of a vitamin or suppliment make sure you know what you are taking and in what dose. Whatever b6 your body doesnt use gets peed out 
Oh btw did you say “if i eat half a banana ill get a lucid dream” and then ate 2?
Thanks for the comments.
I meant that you don’t need a lot of B6 to help you induce lucid dream.
2 Banans are enough(they contain 1.6), so if you want to take a B6 pill, take the multi-vitamin pill and it will be enough, no need to take 200mg!
That may be true, but most of what the body needs it gets from foods. Many suppliments people take are unnessacary. B6 may or may not help you lucid dream, however they can induce the placaebo effect where you believe it will work so it does for you, especially with something so psycological as lucid dreaming. That being said, the daily recomended intake of vitamin B6 is between 50-200mcg*. (*based on a 2,000 calorie a day diet) and as I said B vitamins are water soluable so no worries if you take more than needed as your body will take what it needs and flush out what it doesn’t.
The real problems come when you DONT get enough vitamins.
As for how much B6 to take before bed, I couldn’t tell you. But if you mess around with the dosage you migh find what works for you (if you haven’t already with the bananas)
One more thing is that bananas have more than just b6 in them, they also have pottassium, protein, fiber, magnesium, phosphorus, calcium, sodium, iron, selenium, magnese, copper, zinc, and vitamins A, B1, B2, naicin, folate, pantothenic acid, B6, C, E and K among other viatimins in small amounts, so it could be B6 or a combination of vitamins that could help you lucid dream. 
Try milk, or yogurt. Helps alot for me, not to much LD but i remember more my RD