Dietary fiber is an essential part of a balanced diet and should be included in healthy meals on a daily basis. Athletes can also enjoy the benefits a high-fiber diet provides. We’ll answer the following questions in this post:
1. What is dietary fiber?
Dietary fiber is the parts of unprocessed – almost always plant – foods that your body can’t digest. There are two kinds of fiber: soluble and insoluble.(1) They play important roles in digestion and your metabolism.
What is soluble fiber?
Soluble fiber absorbs water in the colon and turns into a gel-like substance. You can thank soluble fiber for your regular bowel movements. They have a prebiotic effect, which means they provide nutrients to intestinal bacteria, protect intestinal mucosa, and ensure healthy gut flora.
Soluble fiber is found in these foods:
- Fruit (e.g. apples and pears)
- Vegetables (e.g. carrots, artichokes, and onions)
What is insoluble fiber?
Insoluble fiber does not absorb water and can’t be broken down by gut microbiota. As a result, it keeps you feeling full longer and stimulates your digestion. Insoluble fiber is especially effective in preventing or treating constipation.
Insoluble fiber is found in these foods:
- Whole-grains and whole-grain products
- Fruit and vegetable peels
Good to know:
High-fiber foods usually contain different proportions of both soluble and insoluble fiber. If you include a variety of foods and colors in your diet, you will get plenty of both.
2. Why is a high-fiber diet so healthy?
A diet rich in fiber has a number of health benefits.
A high-fiber diet supports gut health and digestion. It ensures regular bowel movements and keeps you feeling full longer. Eating a diet rich in fiber has also been shown to reduce the risk of colon cancer.(2) When you consume a lot of dietary fiber, it’s important to stay hydrated.
A healthy gut is closely tied to a strong immune system. A high-fiber diet can strengthen your immune system. How does this work? The fiber feeds the healthy microorganisms living in our digestive tract which build healthy microbiota.(5)
Did you know?
Frequent consumption of fiber from plant-based foods is associated with a reduced risk of obesity. (7) These foods take longer to digest which keeps you full longer, thus lowering the risk of overeating.
A high-fiber diet also plays an important role in treating type 2 diabetes.(8) Since fiber is digested slowly, it stabilizes the blood sugar and keeps it from spiking, which is what happens when you eat white flour products.
3. How much fiber should I eat per day?
A healthy adult should consume between 25g and 38g of fiber each day.(9) There is no limit to how much at the moment; many adults struggle to even reach the recommended amount.
Are you ready to start changing how you eat and including more dietary fiber, but you’re wondering how to do it? Be careful to increase your fiber intake gradually to prevent bloating. It’s also very important to drink enough water. If you don’t, you may experience constipation.
4. What should athletes consider when eating a high-fiber diet?
Athletes can also enjoy the benefits of a high-fiber diet listed above. The goal should always be to cover your fiber requirements with natural foods, rather than opting for nutritional supplements.
Typical foods for runners, such as whole grain pasta, oats, and broccoli, are almost always a good option. Why almost always? In sports nutrition, it’s important to time your meals properly. A high-fiber diet has a lot of benefits for athletes, by it can also cause digestion problems (feeling too full due to slower digestion, bloating, etc.) Everyone handles fiber differently.
If you eat a meal high in fiber before a workout, it can slow you down. Carbohydrates are the best choice before a workout in order to fill your glycogen stores and give you the energy you need.(10) Make sure to stick to carbs that are easy to digest right before exercising.
You might want to reduce fiber to a minimum on race days to avoid any problems. The most important thing to remember is never experiment with food on those days. Stick with what you know works well for you.
What should I eat on workout days?
Wondering what you should eat to perform your best during endurance or strength workouts? You’ll find everything you need to know in our nutrition guide.
Example of a high-fiber meal plan on workout day
We’ve put together an example of how you can integrate high-fiber foods into your workout day. Have a low-fiber snack before your workout:
- Breakfast: oatmeal with apples, flax seeds, and nut butter
- Snack: plain dairy or soy yogurt with berries
- Lunch: sandwich with hummus or cheese, baby spinach, tomatoes, and cucumber on whole grain bread
- Pre-workout snack: banana or slice of white bread with honey
- Post-workout snack: protein shake
- Dinner: brown rice with vegetables, kidney beans, and chicken or tofu.