The best source of fiber is Mother Nature.

Quick, what one nutritional component are 97% of Americans deficient in? Iron? Guess again. Bone-strengthening calcium? Nope. I’ll give you a few hints (or one that is really hard to chew on): your body cannot digest it. Yes sir/ma’am, according to the United States Department of Agriculture, only approximately one out of every 33 of us is consuming enough roughage in our daily diet to meet current recommendations for optimal health. Every morning when I check my PubMed and ScienceDirect feeds, contemporary science keeps providing more evidence that this “eating healthy” thing is really simple.

According to the latest studies, the average daily intake of fiber for American adults is approximately 15 grams. That’s equivalent to about a single cup of most legumes (lentils, black beans, lima beans, you name it), a whole medium-sized avocado, or two (one cup) servings of your favorite berry. Current recommended daily amounts (RDA) of fiber are 38 grams for adult males and 30 grams for adult women, though we don’t have any current evidence to suggest there are negative side effects to consuming much more—unless you suddenly and dramatically increase your intake, consume it all in a short period of time, or have specific medical conditions, such as irritable bowel syndrome. To put things in perspective, anthropological studies suggest that just a few decades ago the average American was consuming three times today’s average intake. Our ancestors, whose foraging and hunting didn’t take place at the clearance aisle of Walmart, consumed 100 grams or more—per day. In the time since average daily fiber intake has decreased threefold, we’ve seen a similar increase in rates of obesity and comorbidities such as diabetes. Coincidence?

Roughage, bulk, fiber is technically a carbohydrate, except that your digestive system does not have the capability to break it down and turn it into sugar, which is used for energy or stored for future use (as adipose). Fiber passes through the intestinal tract, doing all kinds of cool stuff before it is excreted. By simply taking up physical space, fiber slows down the digestive process, resulting in better glycemic control, increased satiety, easier weight management, and it may influence the composition of our intestinal flora, which we are only beginning to comprehend the importance of. While it can get much more complex (i.e., soluble vs. insoluble fiber), you can leave the particulars to us scientists. Make efforts to eat, and futilely attempt to digest, a lot of fiber and your health and well-being will improve.

Before you pinch your nose and knock down a spoonful of Metamucil® with an orange juice chaser, it really isn’t about the fiber as an isolated component of our diet. At least according to what the latest research comparing the influence of a whole food diet versus a fiber supplement suggests. If we want to get down to it, I tend to believe that the single greatest issue in modern nutrition is the “vitamin-izing” of our diets. And there is a growing body of evidence to support this opinion. A fascinating study recently published in the Journal of Health Psychology suggested that when most people see an orange, they don’t see a deliciously sweet and healthy whole citrus fruit, but vitamin C. In my opinion, which is shared by quite a few other talking heads in the nutrition and health sphere, this is the result of decades of deconstructing food in attempt to understand how it all works. We’ve advanced the science, but is it helping us foster improved health outcomes? If that box of cereal prominently states its contents provide 20 grams of fiber per serving, will it influence your health more positively than a serving of broccoli which contains approximately 4 grams? I feel pretty confident in staking my reputation on a resounding “no”. Again, the more we learn, it seems the less we know about the synergy of those substances we insert into our mouth and process in order to fuel human life.

The real takeaway is that the amount of fiber consumed is the single best indicator of where one’s daily calories are coming from. High fiber intake = whole food diet. Foods that have the highest concentration of fiber also tend to be nutrient dense (high nutrient value per number of calories). And it isn’t physically easy to eat enough unprocessed fiber-dense food to consistently gain weight—even my gut has mechanical limits. You ever tried eating five apples in one sitting? Supplementing with a fiber-enriched product, especially if it is based on highly bioavailable whole food extracts, can be invaluable for the convenience factor alone, but because we still have such a rudimentary understanding of the symbiotic magic provided by nature’s fuel, trust what Mother Earth has provided for us to chew on first.

Don’t overcomplicate things. Fill your bowls with health. No matter where on the spectrum of dietary beliefs you fall—whether it’s Paleo, Mediterranean, or eating bread by the loaf that you have found works best for your life, your gut, and your goals—focus your dietary behaviors on foods that are close to their natural source. These foods are likely rich sources of fiber and are your best bet for promoting lifelong health and vitality.

Dr. Damian Rodriguez is the health and exercise scientist for doTERRA International, LLC. He holds a doctorate in health science, a master’s degree in exercise physiology, and countless professional certifications. He has spent most of his life researching nutrition, exercise, and the lifestyle behaviors associated with optimal health. Along with his passion for health, as someone who lives with Asperger’s Syndrome, he is also involved in bringing awareness to autism spectrum disorders. There are varying opinions about many health and fitness topics. His opinions are his own and not necessarily that of doTERRA International, LLC. Consult your healthcare provider before making any changes to diet and exercise.