The role between juicing and fiber has been a hot topic as of late, as some misunderstand the role juicing plays in the diet and how fiber affects the body.
Juicing removes some types of fibers from the fruits and vegetables, while others remain.
With this said, there are some times when juicing may not be right, and it is important to understand the role between fiber and juicing.
Does juicing remove fiber?
Juicing does remove some types of fibers from the plant. These are typically the larger, insoluble fibers in a plant, and form the “roughage” that comes out as the pulp left behind from juicing.
Insoluble fiber takes time to break down and digest, and may help a person feel fuller for longer. It also adds bulk to the fecal matter as it passes out of the body, which may help with issues such as constipation and diarrhea.
Other types of fibers remain in the juice. This includes many smaller soluble fibers, and some of these fibers are easy to see as the particle matter in the juice after it separates. These soluble fibers are smaller, and absorb water into themselves, forming a thicker, gel-like substance.
Consuming both types of fiber is essential for digestive health and overall health.
You will not get the same amount of fiber from juicing as you would from eating whole fruit, and juicing is not a replacement for a diet rich in plant foods. However, that is not the function of juicing.
Why juice foods?
Juicing allows a person to fit more of the nutrients and antioxidants from some of their favorite foods into a similar-sized serving.
Additionally, juicing is a great way for people to get some fruits and vegetables into their diet that they do not enjoy otherwise.
Juicing also makes the nutrients found in a given plant food more readily available. When eating the food in a meal, the body takes time to break down the insoluble fibers, carbs, and other nutrients in the meal.
In a juice, the body can simply focus on the juice, allowing for easier digestion and absorption. In this way, it may be helpful to think of juicing as a supplement or concentration of nutrients, rather than purely a source of food.
Juicing is not a replacement for eating whole, healthy food. It is an accent or supplement to an already healthy lifestyle.
Why is fiber important?
Fiber is the indigestible part of many plant foods and is an important part of the diet. Fiber helps with markers of digestive health, including:
- Keeping food moving through the digestive system
- Slowing the digestion of other calorie sources such as sugars
- Reducing insulin spikes in the bloodstream
- Allowing for more nutrient uptake
- Increased feelings of satiety, or fullness, to help prevent overeating
Dietary fiber may also play a role in a number of conditions. For instance, a study posted to Metabolism notes that dietary fiber reduces the risk for type 2 diabetes, cardiovascular disease, and colon cancer.
Diets rich in fiber may also help prevent high blood cholesterol, high blood sugar, and high levels of fat in the blood.
Importantly, many of these fibers, including soluble fibers found in many juices, feed the bacteria in the intestines. Having a healthy, thriving gut bacteria may play a key role in helping to prevent a number of disorders, from digestive conditions and issues with the immune system, to some markers of depression and cognitive conditions.
Getting more fiber
The average person needs about 25-30 grams of fiber each day, for a 2000-2500 calorie diet.
Plant foods are the only source of these fibers, such as:
It is important to include multiple sources of fiber in any diet.
Risks of juicing
There are three main risks anyone should be aware of when juicing.
Loss of fiber
While juicing does provide some soluble fiber, insoluble fiber is still important for overall digestive health. On a daily basis, look for simple ways to add insoluble fiber to the body without adding too many extra calories, such as:
- Flax seeds
- Chia seeds
- Leafy greens such as spinach and kale
With this said, an otherwise healthy person doing a reasonable juice cleanse of 1-3 days is unlikely to have any health risks from the lack of fiber.
Lack of protein
Juices lack sources of protein compared to many other foods. It is important to find these sources of protein elsewhere, whether through plant or animal sources.
Juicing tends to use many more fruits or vegetables to get a serving than a person would normally eat in one sitting. This can increase the person’s overall sugar intake. It is important to find ways to balance this sugar intake, such as by eating more dietary fiber.
The bottom line
The topic of fiber and juicing can be confusing.
To make it clear, juicing is more of a concentrate of the nutrients and antioxidants found in the food. However, juicing should not be the only source of fruits and vegetables in the diet.
While most juices will still contain some fiber, it is still important to reach the daily fiber recommendations each day using many dietary sources.
Adams, S., et al. (2018). Interactions of dietary fibre with nutritional components on gut microbial composition, function and health in monogastrics. https://pubmed.ncbi.nlm.nih.gov/29745332/
Kaczmarczyk, M. M., et al. (2012). The health benefits of dietary fiber: Beyond the usual suspects of type 2 diabetes mellitus, cardiovascular disease and colon cancer. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3399949/
Kolodziejczyk, J. K., et al. (2012). Associations of soluble fiber, whole fruits/vegetables, and juice with plasma Beta-carotene concentrations in a free-living population of breast cancer survivors. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3491579/
Müller, M., et al. (2018). Gastrointestinal transit time, glucose homeostasis and metabolic health: modulation by dietary fibers. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5872693/
Wong, J. M. (2014). Gut microbiota and cardiometabolic outcomes: influence of dietary patterns and their associated components. https://pubmed.ncbi.nlm.nih.gov/24898225/