by | Apr 28, 2024 | Healthy Living
How Much Fiber Do I Need to Eat?
No matter how hard you try, your three-year-old won’t eat vegetables, won’t touch oatmeal, and seems to be constantly constipated. Eating out has become more of a chore and far less enjoyable, especially since they turn their nose up at most items at your favorite restaurants.
If you aren’t sure if your child is getting enough fiber, your concern is well-founded. Surveys conducted measuring fiber consumption indicate that only 5% of the U.S. population meets dietary recommendations. The lack of fiber intake is leading experts to be increasingly concerned about this public health issue as fiber intake has dropped significantly since 1977 particularly so among non-Hispanic Whites and non-Hispanic Black people who fell far short on fiber density intake.
What is Fiber?
Dietary fiber is a form of carbohydrate derived from plant cells that is broken down only minimally by digestive enzymes. There are two significant types of fiber: water-soluble and water-insoluble, each with different properties and characteristics.
- Water soluble fiber absorbs water during digestion forming a gel-like substance slowing digestion, increasing nutrient absorption, and creating bulkier stool. Soluble fiber is found in fruits (apples, oranges grapefruits), vegetables, legumes (beans, lentils, peas), and grains (barley, oats, bran).
- Water-insoluble fiber does not change during digestion. It helps soften the stool and prevent constipation while assisting food and waste to pass through the gut more easily. Insoluble fiber is found in fruits with edible seeds and peels, root vegetables, whole grain items (bread, pasta, crackers), bulgur wheat, beans, bran, rolled oats, brown rice, and buckwheat.
How Important is Fiber?
Keeping us ‘regular,’ bulking up our stool to help prevent constipation and hemorrhoids and helping us feel satiated so we eat fewer calories are important benefits of fiber, but fiber does even more. Fiber plays a role in helping to protect us from heart disease and cholesterol, and for some, reduces inflammation. The World Cancer Research Fund reports consumption of foods containing fiber-rich whole grains lowers the risk of colorectal cancer. High-fiber diets are associated with overall lower rates of mortality
A low-fiber diet is widely thought to contribute to asymptomatic diverticulitis, but this was based on a 1960s hypothesis that has yet to be proven. The cause of diverticulosis is still not well understood.
One type of fiber found in whole grains and plants is called arabinoxylan fiber (AX), some of this type of fiber is water soluble, and some is not. Inulin fiber (LCI) is a soluble starchy fiber found in a wide variety of fruits, vegetables, and herbs. Researchers have discovered that these two fibers produce different results according to different health markers. Lower cholesterol and a reduction in bile acids that cholesterol creates were associated with AX while increased beneficial gut bacterium were associated with LCI. It is important to note that LCI fiber contains the prebiotic fructan which can cause significant digestive distress among those who suffer from Irritable Bowel Syndrome (IBS). These soluble fibers can help reduce total blood cholesterol, blood glucose levels, and decrease the risk of heart disease. In one study of fiber supplements, some participants saw an increase in inflammation when they used an LCI supplement along with an increase in a biological chemical that can signal liver damage.
Your child needs to get fiber however they can, but it’s best to get it through a variety of real foods. If you are looking to reduce your cholesterol or blood pressure, plant-rich fiber will help the most. Supplements have their place; however, each delivers different health benefits based on their level of solubility and how each person’s gut processes them. The type and amount of fiber needed varies according to the make-up of each person’s gut.
As you work to increase your fiber consumption remember to:
- Drink fluids— some types of fiber absorb water, so being well hydrated can help prevent uncomfortable bowel movements
- Check labels— when buying packaged foods, check the nutrition label for fiber content as it can vary between brands
- Start slow— increase your fiber intake gradually over a few weeks to avoid intestinal gas, diarrhea, cramping, and bloating
How Much Fiber Should I Eat?
How much daily fiber your child needs depends on their age and how many calories they need to consume each day. The United States Department of Agriculture suggests the following dietary guidelines for Americans:
- Children 12 to 23 months –19 grams of fiber per day
- People 2 years and older—14 grams of fiber per every 1,000 daily calories
According to the USDA, the current American diet consists of just 8.1 g of fiber per 1,000 calories while other studies place average adult intake at 15 grams a day. That’s just half of what the American Heart Association recommends. The organization’s eating plan recommends adults get 25 to 30 grams of fiber from a variety of food fiber sources, not supplements. To date, the health effects of purified fiber supplements haven’t been well-studied. There are no dietary guidelines specifically related to insoluble and soluble fiber intake, however, many experts recommend that 6-8 grams of fiber per day come from soluble fiber sources. As elimination diets such as “paleo,” “keto” and gluten-free have become more mainstream they are contributing to the avoidance of fiber-rich whole grains and the health benefits they can provide.
If you are looking to increase your family’s fiber intake, remember that fruit or vegetable juices have no fiber, and while dried fruit has more fiber than fresh, it also contains more calories where added sugar is involved. When choosing fruit, aim for fresh fruit with an edible peel for increased fiber.
Is Fiber Hiding a Secret?
Your microbiome is the bacteria, fungi, viruses, and other microbes that live in communities inside your body. Your microbiome is critical to your health and immune responses. High-fiber foods help increase the microbiome in our guts. Our gut microbiota, or microorganisms, require a certain balance to function properly while digesting our food and stimulating our immune system. A healthy microbiome can also play a role in improving the odds of tumor response during immunotherapy.
A lesser-known fact about undigestible dietary fiber is that it ferments in the gut and becomes a food source for our colon’s microbiota providing crucial microbial diversity. This fermented food helps maintain the mucus barrier that protects our colon from disease. Purified fiber supplements have the opposite effect, reducing gut microbial diversity.
As you eat more fiber, your body’s ability to process it tends to increase, but it can also cause unwanted intestinal issues. The increase in beneficial gut bacteria does have the side effect of producing gas leading to bloating. Some people are more prone to bloating, but it’s possible that bloating is a sign of significant positive modification to the gut’s microbiome, an increase in diversity. Diets high in plant protein fiber (beans, legumes, nuts) may cause more bloating while diets higher in carb-based proteins produce less. If you suffer from bloating as you try to eat more fiber, you might find relief by reducing your intake of salt.
A small sample observational study noted that those who eat a higher fiber diet tend to respond better to melanoma cancer immunotherapy. Researchers found a connection between each additional 5g of daily fiber intake and a 30% decrease in the risk of cancer progression and death.
A few foods providing 5g of daily fiber include:
- 1 cup of boiled and chopped broccoli
- 1 cup of quinoa
- 1 cup boiled turnip greens
- 1 medium pear
- 1 medium apple
Fiber is More Important Than You Think…
There may be more to the axiom “you are what you eat” than we think! The low-fiber diets of today may have an unintended effect on future generations. In 2019, the Stanford School of Medicine conducted a study of low-fiber diets typical in industrialized societies. They fed mice typical low-fiber diets known to decrease the diversity of the gut microbiome. They found that the diet created internal deficiencies which were passed to future generations causing an irreversible loss of crucial gut microorganism diversity.
It is theorized that ancestral humans may have eaten as much as 100 grams of fiber in a day. North American adults average only 17g with slightly higher intake in European countries. Given the complexity of fibers and how the body reacts to different ones, it is challenging to understand how much of each type we should eat or how to combine each source most beneficially. Most people fall short of meeting daily food-based dietary fiber guidelines.
It can be challenging to abandon the typical American diet with its highly processed foods that lack sufficient fiber, but the first step begins with awareness followed by simple adjustments such as making half your grains whole and choosing a daily serving of a pulse (dry peas, chickpeas, beans, and lentils). As we become more aware of what our bodies need, we can have fun experimenting with the foods of different countries as we seek out more substantial sources of fiber and work to incorporate them into our diets and lifestyles.