Fibre: The Nutrient Most People Are Chronically Deficient In

Only around 5% of adults in Western countries meet the recommended daily intake of dietary fibre. The consequences are well-documented across multiple health outcomes, yet fibre remains one of the least discussed nutrients in mainstream health conversations.

How Much You Actually Need

The NHS recommends 30g of fibre per day for adults. The average UK adult consumes around 18g. The average American consumes 15g. Getting to 30g requires intentional food choices — it does not happen automatically on a modern diet that includes processed foods, refined carbohydrates, and limited vegetables.

Two Types, Both Important

Soluble fibre dissolves in water and forms a gel-like substance. It slows digestion, reduces the glycemic response to meals, lowers LDL cholesterol by binding bile acids, and feeds beneficial gut bacteria. Oats, beans, lentils, apples, and psyllium are excellent sources. Insoluble fibre does not dissolve — it adds bulk to stool, speeds intestinal transit, and reduces constipation risk. Wheat bran, whole grains, and the skins of vegetables and fruit are primary sources.

The Gut Microbiome Connection

Fermentable fibres (a subset of soluble fibre) are the primary food source for beneficial gut bacteria. When these bacteria ferment fibre, they produce short-chain fatty acids (SCFAs) — particularly butyrate, which is the primary energy source for colonocytes (colon cells) and has demonstrated anti-inflammatory and potentially anti-cancer properties. Low fibre diets are associated with lower microbial diversity, which in turn is associated with increased risk of inflammatory diseases, obesity, and metabolic disorders.

How to Hit 30g Daily

Swap white bread for whole grain (adds 2-3g per slice). Add a portion of beans or lentils to one meal daily (adds 6-8g). Eat the skin on potatoes and vegetables where possible (adds 1-2g per serving). Add a tablespoon of ground flaxseed to porridge or yoghurt (adds 2-3g). Have two pieces of whole fruit rather than juice (adds 4-6g). These changes alone can close most of the gap without requiring significant dietary overhaul.