What is Fiber?
Dietary fiber is a very important component in a healthy diet. It is part soluble fiber and part insoluble fiber—and both are important not only to gut health but to overall human health. Fiber helps to maintain a healthy biome, lower lipids that lead to heart disease, prevent cancer and, not the least important, keep you regular!
So what is the difference between soluble and insoluble fiber?
Soluble fiber is dissolvable in water and very easy for our gut bacteria to ferment into gases and biologically active byproducts in the colon. It feeds the good bacteria in our intestines and some become gelatinous. Insoluble fiber is not dissolvable or digestible but is important in providing bulk to help with moving waste through the gut easily. It also feeds our good bacteria, which contributes to ferment in the gut. Knowing the difference does not really matter, as most whole foods will be a combination of the two and you will get what you need.
Plant-based foods can be broken down into different fiber components. For example, one soluble fiber is inulin, which is a fructan and found in a variety of edible and non-edible plants. Since inulin is beneficial, it is isolated and removed from these plants and then added back into yogurt and granola bars as an ingredient to increase the fiber content. (You could also just eat onions, asparagus, bananas, garlic and Jerusalem artichokes to get all the inulin you’d ever need or want.)
Other soluble fibers are alginates found in algae; raffinose found in legumes; xylose, a breakdown product of hemicellulose and also found in wood; and pectin found in fruit skins. Some examples of insoluble fibers are cellulose found in fruits, vegetables and cereals; chitin found in fungi; hemicellulose found in whole grains like wheat, barley, rye and oat; and lignin found in vegetables. That was just for the geeky readers out there who, like me, get a charge out of minutia.
Now for the health motivators! Why eat high fiber? Here you go….
Fiber makes you feel full and causes that satiety to last longer. This results in eating fewer calories than in a similar meal without fiber. Thus, fiber is related to lower obesity rates. Anyone battling excess weight would benefit from eating more fiber with each meal and snack consumed throughout the day.
Fiber binds to bile acids in the small intestine resulting in decreased formation of bad cholesterol in the blood. These bad cholesterols are what lead to plaque formation in the arteries causing heart disease and heart attacks. This is why the American Heart Association recommends eating a high fiber diet.
Fiber improves the good bacterial activity in the gut. Fiber acts as a prebiotic, which means it feeds the good bacteria, a.k.a. biome, that are crucial to our health. This biome increases in number and activity as a result of healthy fiber intake. The bacteria in the gut ferments the fiber and affects gene expression in the large intestine, improving gut function, immune system function and inflammation, as well as glucose and lipid metabolism.
Fiber helps to regulate glucose (blood sugar) metabolism and decreases diabetes risk— but the exact mechanism of how it works is not fully known. However, we do know that one type of insoluble dietary fiber increases insulin sensitivity, which leads to healthier glucose metabolism.
Fiber has been associated with lower risk of colon cancer by balancing intestinal pH and stimulating intestinal fermentation creating short-chain fatty acids—among other mechanisms yet to be uncovered. Women who ate the most fiber (12-25 grams) in one large 20-year study had a 20 percent reduction in breast cancer.
Fiber increases the bulk and improves the consistency of the end result of digestion, the “poop.” Healthy fluffy fiber-full poop moves through the large intestine easily and elimination becomes effortless and painless, which you may take for granted if you have never had a problem with constipation. But anyone who suffers from constipation knows that hard, slow-moving poop causes a lot of discomfort not only with painful, sometimes bloody defecation, but also with chronic abdominal cramping and pain from colonic distention.
How much fiber should we eat in a day?
If you eat a whole-foods, plant-strong diet, then there in no need to count grams as you will be getting plenty of fiber naturally. The best way! But for you counters out there, you should shoot for about 25-30 grams of dietary fiber per day. The foods highest in fiber are legumes, fruits and vegetables, whole grains, nuts, seeds and dried fruits. Figure 1 will help guide you toward foods that are higher in fiber.
The standard American diet (pizza, French fires, soda, you know….the whole array of processed, packaged refined foods) is lacking not only in vitamins, minerals, antioxidants, phytonutrients—but also in fiber. For example, if your breakfast comes from a box in the freezer or from a shelf—like frozen waffles or Cheerios—there will be minimal fiber left after all the refining of the grains, maybe 1 gram. But if you eat a whole grain like oatmeal or millet as your breakfast cereal, you will get 4 grams of fiber.
Try the following recipes that say “Hi to Fiber!”
Breakfast Oatmeal for One
1/2 cup old-fashioned oatmeal, combine with 1/4 cup water and 1/3 cup nut milk, heat until cooked (1-2 min in microwave or a few min on the stove)
Add the following to increase the fiber content:
handful of berries: raspberries and blueberries
a few walnuts and sliced almonds
sprinkle of chia seeds
sprinkle of hemp hearts
sprinkle of ground flaxseed
handful of dried apricots – unsulfurated ones chopped up
Delicious Lentil Soup
1 onion, chopped
3 cloves of garlic
2 carrots, sliced
2 celery stalks, sliced
2 tsp. curry powder
1 tsp. turmeric
2 tsp. ginger powder
4 cups of vegetable broth
1 cup lentils
3 scallions, chopped
1 tsp. apple cider vinegar
1 tablespoon nutritional yeast
salt and pepper to taste
In large pot, sauté all the vegetables (except scallions) and spices in some of the broth until soft. Add the rest of the broth, lentils and the remaining ingredients and simmer on low for 40 minutes, until lentils are cooked as desired. Season and serve.
Black Bean, Corn and Edamame Salad
1 can back beans drained
1 can chickpeas
1 cup frozen corn
1 cup edamame, cooked for 5 minutes
1/2 cup scallions
1 tablespoon olive oil
2 tsp. red wine vinegar
1 tsp. hot sauce
salt and pepper to taste
Toss together all the vegetables and beans. Mix the dressing and toss with the salad.
Chickpeas with Roasted Garlic
1-2 heads of garlic with cloves divided and peeled, depending on your love of garlic. In a 400-degree F oven (205 degrees C), roast the garlic in 1 tablespoon olive oil for 10 minutes.
1 onion chopped
2 stalks celery sliced
1 red pepper chopped
1 can chickpeas
1 tsp. smoked paprika
1/4 dried chipotle pepper
2 tablespoon lemon juice
2 tsp. red wine vinegar
1/4 cup sliced olives of your choice
2 scallions sliced
1/4 tsp. sea salt
1/8 tsp. black pepper
2 tablespoon chopped basil
2 tablespoons chopped parsley
Sauté onion, celery and pepper in olive oil for 3 minutes. Add the chickpeas and spices and cook another 7 minutes. Toss with the remaining ingredients and the roasted garlic and serve.
The Power of Legumes
I included mostly bean recipes herein because this challenges most Americans more than cooking up some vegetables or eating an apple, some grapes or a handful of nuts and seeds—all of which easily will add a dose of fiber to your day. Legumes are packed with fiber and they are a low fat, high protein and extremely nutritious—but underutilized—food in the American diet. So expand your horizons and say “Hi to Fiber!”
Sandra Musial, M.D., is a pediatrician who believes that the foundation of a healthy life starts with healthy food. Growing up, she was inspired by her father, who had a keen interest in nutrition. She earned a B.S. in Nutritional Sciences and then went on to get her M.D. from the University of Massachusetts Medical School. After training as a pediatrician, Sandy worked in private practice for 13 years, where she focused on children’s health and wellness, as well as breastfeeding. She then joined Hasbro Primary Care as an Assistant Clinical Professor of Pediatrics at Brown University, teaching the pediatric residents and medical students. Working with an increasing number of undernourished obese children, she was motivated to train at the Institute for Integrative Nutrition® to earn a certificate in Health Coaching. Though she has witnessed the healing power of allopathic medicine, she has also seen its limitations, especially with regard to disease prevention through healthy nutrition. Sandy helps others find their optimal health by exploring the various facets of health and wellness, and making changes toward a healthier whole life. Sandy enjoys gardening, yoga, knitting and sweater alchemy. For more information visit www.healthcoachconnect.com