Thanks for your comments:
I have googled for recommended daily intake of fibre and found that it differs depending on the age and sex:
Men 19-50 years old 38 grams
Men 51 and over 30 grams
Women 19-50 years old 25 grams
Women 51 and over 21 grams
So should there be a different version for men and women? To me, it actually sounds like a very good idea. For example, Soylent has 27g of fibre and Mana 21g of fibre. So I guess there are different approaches on how much one should eat.
Maybe it would be nice to also have a blog post about fibre effects, similar to the one you have for protein. What are exact effects of fibre? My naive idea is that it somehow cleans our intestines, right?
Might too much fibre be causing a constipation? And what is the difference between soluble and insoluble fibre?