Fibre slows digestion, feeds the bacteria in your gut, steadies blood sugar, and keeps things moving. Most adults get about half of what they need. The target is roughly 25–35 grams a day, and almost nobody hits it by accident.
Two kinds matter. Soluble fibre — oats, beans, apples, chia, psyllium — forms a gel that softens stool and blunts blood-sugar spikes. Insoluble fibre — whole grains, vegetable skins, nuts, seeds — adds bulk and keeps transit regular. Real food gives you both.
Increase it gradually and drink more water as you do. Doubling your fibre overnight is how people conclude fibre 'doesn't agree with them' — it was the speed, not the fibre.
Constipation is one of the most common complaints on a GLP-1, because food volume drops and everything slows. Soluble fibre, fluid, magnesium, and daily walking fix most cases; tell your prescriber if it doesn't budge.