This is what it says in the bumph (which makes it no clearer, but hey, I need another helpful badge)
Fibre in Huel Ready-to-drink
Huel Ready-to-drink contains 5.7g of fibre per bottle. The fibre in Huel Ready-to-drink is a mixture of soluble and insoluble forms all naturally supplied from oats, flaxseed and chicory. This fibre profile helps to ensure the formation of normal, solid stools in healthy users.
Fibre acts like a sponge, so it’s important to include lots of fluid in a fibre-rich diet (20). As Huel Ready-to-drink is made with water, there’s plenty of fluid supplied, but we do recommend you also include plenty of water in your diet.
The Huel Ready-to-drink formula has been designed to maintain optimum digestive system health, and there are also other benefits from its fibre profile: you may well have heard about the beneficial soluble fibre in oats called beta-glucan; well, Huel Ready-to-drink contains good amounts of this cholesterol-lowering fibre, ideal for a healthy heart (21).