Cellulose is a carbohydrate, which means it is made up glucose. Glucose is the main source of energy for our body. But even though we eat plenty of cellulose our body cannot tap into its energy, which is a substantial amount. Instead, the health benefits of its consumption is as a source of insoluble fiber.
The reasons cellulose is not a source of energy for humans has to do with bonding. During digestion, food is broken down into a usable form with the help of enzymes that break bonds between glucose molecules. Our body does not produce the digestive enzymes required to break cellulose bonds. In fact, most living organisms do not have what it takes either.
Yet, many plant eating mammals (e.g. cows, sheep) can reap the benefits of the huge energy source from cellulose because of their intestinal flora. In other words, their gut contains certain intestinal dwelling bacteria that have what it takes, while those bond breakers do not reside in our digestive tract.
Although cellulose is not metabolized for energy, its staying intact does provide a huge health benefit as fiber. Undigested cellulose increases stool size and helps keep stuff running smoothly through your digestive tract. Therefore, eating a high cellulose diet is very beneficial toward everyday comfort by preventing constipation. (Most appreciate that being constipated causes a bad feeling until the bowels move.)
Dietary fiber is naturally a part of plants, so commonly known food sources are fruits, vegetables, nuts and whole grains. However, those preferring to subsist on processed food get cellulose in their diet as well. Only you may not know it because it is used as an additive for a variety of reasons. And much of this added cellulose is derived from wood.
Tree cellulose is commonly added to reduced fat, low calorie or high in fiber labeled processed foods. It is also used as a filler for profit. So this might explain why some manufactured food tastes like cardboard or sawdust. Because it is!
Those in support of using cellulose from wood argue it’s just harmless fiber. Yet, consuming dietary fiber from edible plants is brought to you with nutrients the way nature intended. So choose healthier sources of cellulose nature makes and not the wood filling junk man produces.