The ancient fiber problem

The fiber problem is older than GLP-1. Human diets historically contained substantially more fiber than modern Western diets. GLP-1's reduced food intake makes that deficit even more acute for people already eating far below historical norms. The link between dietary fiber and bowel health was formally established in Western medicine by Denis Burkitt in the 1970s. A British surgeon working in Africa, Burkitt observed much lower reported rates of constipation and several bowel diseases compared w

One tablespoon fixes a lot

Chia seeds are one of the easiest fiber fixes in the world. A tablespoon in yogurt or water gets you 5 grams of mostly soluble fiber with almost no flavor and no cooking. Overnight oats with chia and a handful of berries is zero work and dramatically shifts fiber intake. Legumes are another practical option — half a cup of lentils or black beans delivers 7 to 8 grams of fiber in a small, soft portion. Add them to soups, stir them into eggs, keep them cold in the fridge for easy small meals. On G

The oldest laxative that still works

Prunes are genuinely worth trying.

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May 30, 2026

👖 Why am I constipated on GLP-1?

Note: This article is for informational purposes only and does not constitute medical advice.

The last bowel movement was three days ago. On GLP-1, that is not unusual.

Constipation is one of the most common reported side effects on GLP-1 medications — and the physiology behind it is fairly straightforward. GLP-1 receptor agonists can alter gastrointestinal motility beyond the stomach, which may contribute to constipation alongside lower food and fluid intake. Lower motility plus lower food volume can slow transit overall.

Most people on GLP-1 are eating so much less that fiber intake drops dramatically without realizing it. Dietary fiber increases stool bulk and water retention in the colon, and feeds microbiota that produce short-chain fatty acids — particularly butyrate — which support colonocyte health and may influence colonic motility. When fiber intake drops, both of those effects may diminish.

Dehydration compounds the problem. The colon reabsorbs more water from stool when the body is dehydrated, making stools harder and more difficult to pass. On GLP-1, reduced appetite often means reduced fluid intake alongside reduced food intake — both need active attention.

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About this article

Foodbe.ai exists to inform consumers about the food they buy and eat. Every claim is cited. Sources: NIH, USDA, FDA, Smithsonian, and JSTOR. Found an error? Email us at admin@foodbe.ai to report any source or fact issues.