Dietary fiber decreases the metabolizable energy content and nutrient digestibility of mixed diets fed to humans

D J Baer, W V Rumpler, C W Miles, G C Fahey
Journal of Nutrition 1997, 127 (4): 579-86
Food labeling regulations implemented by the U.S. Food and Drug Administration emphasize nutrient composition and energy content of foods. Dietary energy and digestibility of complex foods can be affected by the content and type of dietary fiber. The metabolizable energy (ME) content and apparent digestibility of dietary fiber in human diets are difficult to assess. Fiber can affect the digestibility of fat and protein and, subsequently, the ME content of the diet. This study was conducted to measure the ME content of nine diets with different fat and fiber concentrations. Diets varied in level of fat (18, 34 or 47% of energy) and level of total dietary fiber (3, 4 or 7% of diet dry matter) and were consumed for 2 wk. Subjects (n = 17) consumed three diets (14 d for each diet) containing different levels of fiber and one level of fat. Food consumption was measured and all urine and feces were collected during a 5-d period. Combustible energy, protein, fat, total dietary fiber (TDF) and neutral detergent fiber (NDF) were measured in composite samples of food and feces, and urine was analyzed for combustible energy and nitrogen. Metabolizable energy and apparent digestibility coefficients were calculated. Overall, increasing fiber intake decreased fat and protein digestibility. As a consequence of these interactions, the ME content of the diets decreased as fiber intake increased, and TDF and NDF had similar effects on the ME value. A published empirical formula accurately predicted the ME content of diets using either TDF or NDF.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"