Fiber fueled is a book by gastroenterologist Will Bulsiewicz. You can buy the book at bookshop.org.* In his book, he writes about the gut microbiome and how it affects your health. Fiber is the key to diversifying and healing your microbiome.
This book is very special to me since it inspired me to create fiberfoodfactory blog. It really opened my eyes to how important a healthy gut is to our health and how eating fiber and a plant-based diet can improve our microbiome.
Content in the book
The book has three parts. The first part tells about the gut microbiome and damage to the gut microbiota(dysbiosis). Dr. B writes about different medical conditions related to dysbiosis. He also tells what type of diets and foods cause this.
In part one, the book also explains how eating fiber makes the microbiome create short-chain fatty acids, essential to our health.
The second part discusses how important it is to eat diverse foods and eat the rainbow, meaning different colored foods to get phytochemicals.
The second part also explains how you should eat with a sensitive gut. If you should consume gluten, milk, lectins, and soy. The second part also has a chapter about fermented foods and why we should eat them.
Dr Bulsiewicz also explains his F GOALS in how you should eat:
- F: Fruit and fermented
- G: Greens and grains
- O: Omega-3 super seeds
- A: Aromatics
- L: Legumes
- S: Sulforaphane
The third part has the fiber-fueled plan. He shares a 4-week eating plan with recipes and complete shopping lists. All weeks and recipes also have alternations to low fodmap. So the plan also works if you have IBS. You get more than 65 fiber-rich recipes for a healthy gut.
You can also listen to this great interview by forks over knives where Will Bulsiewicz introduces and discusses his book content.
Part one: your gut microbiome
Your gut has 39000000000000 trillion microbes. Bacteria make our microbiome, and most of the microbes are good, especially if you eat the right way. There are also bad microbes.
The good and bad microbes live in harmony but can also damage your gut. This happens when you get more bad bacteria and less of the good ones. The medical term is dysbiosis.
Homeostasis is a balanced gut. In a balanced gut, you have anti-inflammatory healthy microbes and short-chain fatty acids. Short-chain fatty acids are called SFAs. In a damaged gut you don´t have those fatty acids, SFAs, in a vast amount.
Symptoms of dysbiosis, damaged gut
Here are listed some things mentioned in the book that your gut microbiome affects on. You can check the book references as a pdf in this link.
How the gut microbiome affects your immune system
Dr. Will explains that the majority of your immune system lives in the gut. There is only one layer of cells, the epithelial, between your intestines and the bloodstream. On the other side of the epithelial is your immune system. They are talking to each other constantly. Interestingly, when immune diseases have been studied, they have always found damage in gut bacteria.
Some immune-mediated conditions are associated with dysbiosis:
- Type 1 diabetes
- Celiac disease
- Multiple sclerosis
- Food allergies
- Seasonal allergies
- Psoriasis/psoriatic arthritis
- Restless leg syndrome
- Sjögren's syndrome
- Rheumatoid arthritis
- Ulcerative colitis
- Chron´s disease
- Autoimmune hepatitis
- Guillain-Barré syndrome
- Kawasaki disease
Metabolic conditions associated with dysbiosis:
- Type 2 diabetes
- Coronary artery disease
- Chronic kidney disease
- Nonalcoholic fatty liver disease
- Alcoholic cirrhosis
Some neuropsychiatric conditions associated with dysbiosis:
- Chronic fatigue syndrome
- Restless legs syndrome
- Autism spectrum disorders
- Bipolar disorder
- Migraine headaches
Endocrine and hormonal conditions associated with dysbiosis:
- Polycystic ovary syndrome (PCOS)
- Endometrial hyperplasia
- Female infertility
- Sexual dysfunction
- Breast cancer
- Endometrial cancer
- Prostate cancer
- Erectile dysfunction
This modern culture has affected our gut health. The world has changed a lot in the past 100 years. Then people did not eat processed food and walked a lot more, and were physically active. In history, pesticides were not used as we do now and people ate more locally grown plants. The lifestyle has now changed drastically. We have a lot of chemicals in our foods. Additives are everywhere. In farming, herbicides and insecticides are used. Antibiotics and hormones are fed to animals. All these things affect our microbiome and health.
Short-chain fatty acids are important for your health
SCFAs, short-chain fatty acids, called postbiotics, are formed by the microbes when you eat fiber. In the gut, SCFAs help you to get more anti-inflammatory microbes. They enrich the good guys. They simultaneously suppress the inflammatory microbes such as salmonella, shigella, and e-coli.
In the book Will Bulsiewicz explains more deep on types of SCFAs and what prebiotics and probiotics are. He explains how you can heal a leaky gut and the important role of short-chain fatty acids in diseases; how they are connected to your immune system and protect against cancer, heart disease, stroke and diabetes.
Part 2: A plant-based diet is best for your gut microbiome.
Your gut needs fiber. You only get fiber from plants; all plants contain fiber. There is millions of type of fiber in nature. Fiber is an extremely complex structure. It is often classified into two categories: insoluble fiber and soluble fiber.
Every plant has a unique fiber structure that feeds unique microbes. If you eliminate a food group, those microbes that feed on those fibers get weaker and die.
You cannot affect many things, such as genetics, and mode of delivery of birth. The thing you can control is your diet. Other things that affect the microbiome are for example:
- medicines, such as antibiotics.
- alcohol consumption
Biodiversity is a measure of gut health.
A more diverse diet is a more diverse microbiome. The single greatest factor in the gut microbiome is the diversity of plants in your diet. When your gut microbes feast on prebiotic fiber, they reward you by releasing short-chain fatty acids.
If you are interested to learn more about gut microbiome studies, you can read about the American gut project. From May 2002 to 2008, they took 15096 samples, and 11336 human participants were in it. 42 countries and territories were represented.
Eat the rainbow
In part two the Fiberfueled book goes thru the benefits of eating a lot of phytonutrients you get from different colored foods. The part dives into how you can eat e diversity of plants.
One of my favorite parts was the food sensitivities since they are so common.
In part two Will also shares his sauerkraut recipe on the part of fermented foods.
Part three: The 4 week plan
In this part, you get a complete guide on how and what to eat. The recipes are delicious and all plant-based. Week one recipes include for example:
- Super seedy porridge.
- Roasted Italian medley. I have a similar recipe named Italian roasted veggies.
- Muhammara red pepper spread. Check out my muhammara recipe, but make it without the garlic.
I wrote an article on tips on what you can eat after this 4-week plan. Check it out! It includes a list of recipes.
To get the whole 4-week plan buy the Fiberfueled book. You can get it for example at bookshop.org. *
My opinion of the book
I really liked the book. The book is easy to read. It explains in my opinion all things so the common people can understand it. The book does not dive into the complex structures of types of fiber, and it does not need to. The focus is in well being and how a right diet can benefit you. It makes a deep dive in the right stuff.
After reading this book I think you will change your eating habits and incorporate more plants in your daily diet and eat more variety of foods.
Eating the 4-week plan also helps with weight loss. You might notice becoming some pounds lighter.