I am pretty sure it depend how aroused you are. When wanking I dont cum a lot but when having sex with my bf, i cum a lot.
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Hydration could be your problem... I think sources of vitamin E are also good for the production of sperm, whether that would be for the spermatozoa themselves or for the general production of the fluid, I don't remember. But zinc and water and vitamin E should make for a good combination. I think your dehydration is probably the main problem. Keeping your juice for more than a day will also help, to some extent. But we are continually producing sperm so, it shouldn't be that.
And anyway, don't worry about the quantity of sperm you ejaculate as it's not proof or guarantee of how much you enjoyed coming at all... Just reassure your partner(s) that this is normal for you.
If you still think that the quantities you are spurting are not normal, why don't you collect it once in a spoon and measure how much it was, (since a teaspoon seems to be about normal), and if it really does not seem enough talk to your GP about it, eh? He'll put your mind at rest or tell you what you can do to make things normal again.
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