Cereal beta-glucans

Fermentable fibers

The viscous fiber of oats and barley: it thickens the food bolus and slows everything that passes through it.

They are not the same molecules as mushroom beta-glucans: different bonds, different bacteria.

Effects and benefits

The secret of porridge. In the gut, the beta-glucans of oats and barley form a thick gel that traps some of the bile: to make more, the liver draws on cholesterol. With 3 g a day, they contribute to maintaining normal cholesterol.

Three grams is about 80 g of oat flakes. Oat and barley beta-glucans contribute to the maintenance of normal blood cholesterol levels (Regulation 432/2012). Oat beta-glucan has even been shown to lower blood cholesterol, and high cholesterol is a risk factor in the development of coronary heart disease (Regulation 1160/2011). A meta-analysis of 28 trials puts the drop at about 0.25 mmol/L of LDL cholesterol (Whitehead et al., 2014).

The same gel slows stomach emptying and the passage of sugars: 4 g of beta-glucans per 30 g of carbohydrates in a meal contribute to a reduction of the blood glucose rise that follows (Regulation 432/2012). The thicker the gel, the clearer the effect: whole flakes do better than puffed cereals, whose manufacturing has broken the chains.

In the colon, they end up fermented: in volunteers eating whole-grain barley, butyrate-producing bacteria and bifidobacteria increased (Martínez et al., 2010).

By sex and age: women's LDL cholesterol often rises at menopause, when estrogens no longer hold it down; that is the age when the 3 g a day benchmark makes the most sense.

Sources: EU Regulations 432/2012 and 1160/2011 · Whitehead et al., AJCN, 2014 · Martínez et al., ISME J, 2010

Where to find it (2)

• Barley
• Oats

Also, in smaller amounts (3)

• Beta-glucan
• Rye
• Whole wheat

Its category

Whole grains & seeds