I Added 20 Grams of Fiber to My Daily Diet for a Month — Here’s What Happened

Most of us have experienced a mid-afternoon slump, the bloated feeling after a heavy meal, or the general sense of sluggishness. Contrary to what the social media influencers will have you believe, the solution to most of these problems might lie in something as basic as increasing your dietary fiber intake.

Fiber is the indigestible part of plant foods that sweeps through our gut and keeps our digestive system in top shape.

As a personal trainer with over 17 years in the trenches, I decided to test what would happen if I deliberately added 20 grams of fiber to my daily diet for a month.

In this article, I’ll share my experience with this four-week experiment and how increasing my fiber intake impacted my digestion, satiety, and weight. I’ll also reveal tips on how you can adopt this diet to better suit your lifestyle. We have a lot to unpack, so sit tight and read on.

Note: The content on Fitness Volt is for informative purposes only. Do not take it as medical advice to diagnose, prevent, or treat health problems. If you’re suffering from a health issue, are pregnant, or are under 18 years old, you should consult your physician before starting any new supplement, nutrition, or fitness routine.

The Starting Line: Baseline Assessment of My Fiber Intake

Before I get into the nitty-gritty of this challenge, I want to explain my initial dietary habits and fiber intake so that everything makes more sense to you.

I have been following a hypertrophy-focused training program for a very long time. My typical diet, while generally focused on protein and complex carbohydrates, lacked fiber content.

I consumed a decent amount of vegetables but often neglected high-fiber grains and legumes.  My calorie tracking app tells me that my usual average daily fiber intake hovered around 15 grams, well below the recommended 25-30 grams for adults. (1)

My energy levels fluctuated throughout the day due to my haphazard fiber intake, hampering my training performance. Although my weight remained consistent, I wasn’t satisfied with my body composition.

As soon as I started paying closer attention to my fiber intake, I realized that my occasional digestive sluggishness and bloating stemmed from not consuming enough of this macronutrient.

Sidenote: Most people are surprised when I tell them fiber is a macronutrient as they assume that protein, carbs, and fats are the only three macronutrients. Fiber is a type of carbohydrate because the body needs it in large quantities compared to micronutrients, making it a key component of a healthy diet.

Dialing My Fiber Intake For Best Results

I used this fiber intake calculator to determine my ideal daily fiber intake. Then, I logged every morsell I consumed in my calorie tracking app, MyFitnessPal, to ensure I was moving in the right direction.

When following a similar challenge, you must get comfortable reading and analyzing food labels. I used the MyFitnessPal app to scrutinize serving sizes and fiber content of every food.

Then, I did a quick Google search to look for alternatives if a food item lacked fiber content.

Week 1: Initial Adjustments and Observations

The first week of any dietary overhaul often feels like navigating a minefield to me. I have to constantly remind myself of things I can eat and must avoid throughout the day to stay in line with the new protocol.

Adding 20 grams of fiber kicked my digestion into high gear and increased flatulence and bloating — a common but uncomfortable side effect.

Nonetheless, my bowel movements became more frequent and efficient, which is one of the biggest benefits of increasing fiber intake.

I also experienced an improvement in my satiety as the increased fiber intake left me feeling full and satisfied after each meal. This can be a powerful tool for anyone trying to manage their calorie intake or combat random cravings.

I likely experienced energy fluctuation initially due to the digestive system working overtime to adjust to the new diet. However, my energy levels became more stable after a few days.

Week 2: Finding a Rhythm

My body started adjusting to this new diet after I was over the hump; my gut microbiota started expanding, which helped lowered the bloating and gas.

The high fiber content was now keeping me feeling fuller for longer. At this point, I completely stopped reaching out for those mid-afternoon candy bars. I noticed that my cravings for sugary and processed foods diminished as my blood sugar levels stabilized.

Fiber slows down the absorption of sugars, preventing dramatic spikes and crashes that fuel cravings. This also had a positive effect on my overall productivity and output. (2)

Meal Innovations

In my experience, boredom is one of the biggest reasons why most people quit their diet before achieving their objectives. At this point, I started exploring new fiber-rich recipes to keep this experiment exciting.

I experimented with overnight oats loaded with chia seeds and berries and sprinkled ground flaxseeds on almost everything to add fiber.

A handful of almonds, an apple with peanut butter, or a small bowl of Greek yogurt with a sprinkle of granola became my go-to high-fiber snacks.

Week 3: Significant Changes and Breakthroughs

After the initial discomfort was gone, my body was running more efficiently.

The mid-afternoon slumps had completely vanished, and I was crushing my resistance training workouts like never before.

The role of gut health in your overall mood is highly underrated. As my gut health improved, I noticed a big improvement in my mood and focus. I felt mentally and physically lighter and could handle the daily stressors with more resilience.

My body composition improved — my midsection tightened, and my T-shirts fit a little snug around my shoulders and arms. I had not expected that adding 20 grams of fiber to my daily diet could have such a big impact on my physique aesthetics.

Improved skin glow was the biggest unexpected benefit of increasing my fiber intake. Enhanced digestion means optimal nutrient absorption, and the toxins get flushed out more effectively. This leads to a clearer, brighter complexion and a healthy glow.

Week 4: Solidifying the New Routine 

By Week Four, this experiment did not feel like a chore anymore. My meal prep evolved significantly, and I naturally reached for high-fiber foods. Oatmeal with berries, a handful of nuts, and a side of broccoli became staples in my diet.

Not only did my digestion and satiety improve, but I also lost 8 pounds over these 30 days.

Throughout this month, the benefits compounded. I spread my fiber intake throughout the day to ensure a steady digestion and sustained energy levels.

To be completely honest, I felt a slight sense of “why did I not do this sooner?” since I knew the importance of fiber from the beginning but had not prioritized it in my diet.

I now keep a running list of my favorite high-fiber foods. This way, I never run out of options for my meals.

The 20-Gram Fiber Challenge: Methods and Implementation

Relying on guesswork is a sure-shot way of failing when making a new change in your diet or training program.

I mainly ate whole foods rich in fiber to meet my daily intake targets. My grocery list included:

• Berries
• Apples
• Pears (skin on, of course).
• Broccoli
• Brussels sprouts
• Lentils
• Chickpeas

Whenever I had the option, I chose foods that delivered a solid dose of fiber and protein. Plus, I ditched the white bread and pasta for their whole-grain cousins like oats, quinoa, and brown rice.

I also added fiber supplements like psyllium husk and methylcellulose to bridge any gaps in my diet. Remember, they are called supplements for a reason. You shouldn’t become overly reliant on them to meet your daily nutrient goals.

Daily Meal Plans

This is what my meal plan looked like during this one-month high-fiber challenge:

Breakfast

• Oatmeals
• Berries
• Chia seeds

Lunch

• Large salad
• Grilled chicken
• Chickpeas
• Vegetable mix

Dinner

• Lean proteins like chicken breast or lentils
• Brown rice
• Steamed vegetables

Consider this meal plan a blueprint, and feel free to adjust your diet based on your personal preferences and health objectives. I also encourage you to experiment with the recipes to keep your diet exciting, as it increases your chances of sticking to this healthy meal plan for the long term.

Initial Challenges

My taste preferences presented a minor hurdle as some of these high-fiber foods aren’t exactly gourmet. I used a decent amount of seasoning and combined these high-fiber foods with other ingredients to enhance their flavor.

It did not end there. These meals also required better planning, and I had to prep a week’s worth of food on my day off from work to avoid falling off the wagon.

Long-Term Impact of a High-Fiber Diet and Recommendations

You must balance the two types of fiber to get the most from this new diet in the long term.

Soluble fiber dissolves in water, forming a gel that helps lower cholesterol and stabilize blood sugar. On the other hand, insoluble fiber, which doesn’t dissolve, adds bulk to your stool, promoting regularity.

Whole grains and vegetables should be your go-to sources for both these types of fiber, as they both play vital roles in your overall health.

Although I switched to a high-fiber diet overnight, I won’t recommend you do the same. Too much fiber too quickly can result in significant bloating, gas, and abdominal discomfort. Give your gut enough time to adjust by starting small, let’s say five additional grams of fiber, and increasing it gradually.

Finally, your unique fiber intake goals will vary depending on your current fitness and activity levels and objectives. For instance, athletes might need more carbs, so they should prioritize fiber-rich carbs like sweet potatoes and quinoa. Conversely, people with high cholesterol should focus on soluble fiber.

Experiment with different ratios until you find what works best for you. Keep detailed notes of how you feel, your energy levels, and any changes in your digestion. This data will guide you.

Conclusion

I had only anticipated improved digestion after adding 20 grams of fiber to my routine. The weight loss and stable energy levels throughout the day were a bonus. This 30-day high-fiber diet also reinforced the fact that small changes can yield significant results if you are consistent.

Twenty grams of fiber might sound like a small number, but it can make a world of difference in four weeks. Start small, stay disciplined, and you’ll be rewarded for your efforts in no time. Best of luck!

References:

1. McKeown NM, Fahey GC Jr, Slavin J, van der Kamp JW. Fibre intake for optimal health: how can healthcare professionals support people to reach dietary recommendations? BMJ. 2022 Jul 20;378:e054370. doi: 10.1136/bmj-2020-054370. PMID: 35858693; PMCID: PMC9298262.
2. Giuntini EB, Sardá FAH, de Menezes EW. The Effects of Soluble Dietary Fibers on Glycemic Response: An Overview and Futures Perspectives. Foods. 2022 Dec 6;11(23):3934. doi: 10.3390/foods11233934. PMID: 36496742; PMCID: PMC9736284.

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