Pumpkins should be consumed at an immature age, when the pips are very little formed, and the bark is fine and full.
These pumpkins are very rich in water (almost 95% of their weight), but in the pulp and especially in their shell there are also very large amounts of vitamin B9, vitamin A, phosphorus and potassium.
To get an idea of their richness in vitamins it's enough to say that three hundred grams of pumpkins provide nearly twice the daily requirement for vitamin A and vitamin B9, the daily requirement for phosphorus and potassium, half the daily requirement of magnesium.
Keep in mind that the most vitamins, minerals and other active substances (enzymes, flavonoids) are stored in the shell.
So, if you want to benefit from the therapeutic effects of pumpkins, make sure you buy them healthy, fine and intact, wash them well before cooking, but do not peel off them.