Gut health recommendations consistently proclaim fiber to be the best thing since sliced bread (whole grain of course!). So what exactly is fiber? How do you know if you are getting enough? And is it really all that important? I get these questions a lot in my practice, so I thought it might be helpful to break it down here on the blog.
Fiber is the indigestible portion of plant foods and it does a couple of important things in the body. It adds bulk to the stool, which helps to move food through the GI tract. This is why those following low fiber diets often struggle with constipation. Fiber has an important role in detoxification, binding to and removing toxins, degraded hormones, and excess cholesterol from the body. Fiber also helps slow digestion, positively impacting blood sugar levels. In fact, we have countless studies demonstrating the importance of finer intake to heart health, blood sugar management, weight management, and healthy digestive function. So, yeah, I wo
uld say its a good idea to get adequate fiber in your diet!
Then, there is the microbiome to consider. Fiber is not only good for us, but also, it feeds our gut bugs. Let me just tell you, there are lots of hungry mouths to feed! It is estimated that approximately 100 trillion bacteria reside within us. This is a good thing! They ferment the fiber that we consume, and create all sorts of beneficial by-products, such as short chain fatty acids and vitamins (B group vitamins, C and K). They also impact our hormones, neurotransmitters (like serotonin), and immune system. We want a happy, well fed, and healthy microbiome.
So yes, fiber is good, Preferably, it is best to get it from whole food sources like fruits, whole grains, legumes and vegetables. That way, it comes packaged with lots of other nutritional goodness (vitamins, minerals and phytochemicals). Unfortunately, the average American consumes only 10-15g/day,
which falls way short of recommendations.
It is recommended that men consume 38g per day and women consume 25g per day.
Do the calculation yourself using a meal tracking app like My Fitness Pal. Are you eating that much? Unless you eat tons of plant foods or are supplementing, you may want to take a look at boosting fiber rich foods in your diet.
Here is the part where I confuse you. Sorry!
Not everyone should be eating loads of fiber. In fact, some people should limit their fiber. As is always the case with nutrition, the perfect diet for one person is not necessarily the perfect diet for another. Factors such as personal biochemistry, genetics, environment, history, age, sex, lifestyle, and behaviors all play into what our optimal diet looks like. Then there is the microbiome, made up of 300-500 different bacterial species (1.). It varies dramatically from one person to the next. Some people have too little good bacteria, some people have too much bad bacteria, and some people have bacteria in the wrong place. In fact, many people that come to me with gut complaints are struggling with a condition called small intestinal bacterial overgrowth (SIBO). This is condition where gut bacteria take up residence in the small intestine and cause all sorts of problems.
Common symptoms of SIBO:
An uncomfortable feeling of fullness after eating.
Constipation and or diarrhea
SIBO can also lead to leaky gut, a condition that has been linked in numerous studies to autoimmune conditions, chronic fatigue syndrome, allergies, asthma, obesity and mental illness.
If you have lots of bacteria in your small intestine that are wreaking havoc, does eating tons of fiber to feed them sound like a good idea? No, of course not. That is why people with SIBO often feel worse when they start taking probiotics. So, what to do?
For those with great digestive function and are in excellent health, eating 25-30g of fiber from a variety of plant foods per day is a great idea, for all the reasons that I mentioned earlier. However, for those that suspect gut issues, then the next step would be to better understand what is causing those problems. Is there yeast overgrowth, pathogenic bacteria, parasites, SIBO, or food sensitivities? Understanding the cause of one’s symptoms, will allow for a much more effective treatment plan and dietary recommendations.
If you do have or suspect that you have SIBO, eating that 25-30g of fiber per day may not be the best idea. Eventually, you will want to add those fiber rich foods back in, but for a period, it is important to trim back the bacteria rather than build it up. The most common dietary recommendation is to follow a low Fodmap diet, which is a diet that greatly reduces the amount of fermentable carbohydrates one eats in a day. Depending on the degree of overgrowth, herbal antimicrobials or prescriptive agents may be warranted in addition to dietary change.
You may be thinking, well my gut health is certainly not 100%, but I do not feel bad enough to have someone sort through my poo. I hear you. It is not for everyone. The good news is, regardless of microbiome status, there are actions that everyone can take to improve gut health. Below I have listed my top recommendations.
1. Avoid or at least, greatly cut back on refined carbohydrates.
No surprise here. Cake and ice-cream will not help you to achieve your dream of a flat, toned tummy. Refined carbohydrates, such as those found in baked goods, pasta, pizza, white rice, and anything containing added sugar, are not only high in calories, but also, are linked to increased amounts of the bad kind of gut bacteria (3). At this point in time, there are somewhat limited studies on this topic, but I think it’s safe to say, the less of these foods in your diet, the better off your health.
2. Move your Body.
We know that exercise impacts the gut microbiome in significant ways. It impacts the amounts and types of bacteria that reside within us. For instance, one study showed that exercise promotes the growth of bacteria that produce butyrate, a fatty acid that helps to heal the gut lining and reduces inflammation (4). We also know that for digestive function to perform optimally, we need to move our bodies. This increases peristalsis and the transfer of food through the digestive tract reducing our risk of constipation, and even developing SIBO (5).
3. Drink plenty of water.
Dehydration leads to constipation, increased methane gas production by gut bacteria, and abdominal distension. It is just not a fun situation. Aim for about 2L of water per day, and increase your intake on days when you have increased sweat production or are in a hot environment. By the way, if you are thirsty, you are already behind the 8 ball.
4. Manage your Stress.
That darn stress, always getting in the way! Not only does it impact sleep, blood pressure, weight, and cognitive function, but also, it impacts the state of one’s microbiome, and in a way that appears to increase chronic inflammation. No Bueno. And not only does our mind impact our gut microbes, but also, those meddling little guys impact our brain, going so far as to impact our cravings and eating behaviors (6).
5. Spend time in nature.
Nature makes us happy. Why is that? Is it because of the beauty of mother nature or the inhalation of fresh air? Well, the reality might be less romantic. Yep, I am talking about those gut bugs again! One study found that preschoolers that were exposed to more nature, saw beneficial changes to their gut microbiomes leading to increased serotonin production, and improved behavior as a result. Serotonin is our happiness hormone, and 95% is produced by bacteria in the gut! Though this study had certain limitations, it does present a reasonable explanation for the link between nature, gut health, and happiness (7).
If you are interested in learning more about your personal microbiome, we do offer a Microbiome test at Back to Balance. Shoot me an email if you would like to learn more about the Genova GI Effects stool test.
1. Gastroenterol Hepatol (N Y). 2013 Sep; 9(9): 560–569.
2. J Gastroenterol. 2018 Jul;53(7):807-818. doi: 10.1007/s00535-018-1476-9. Epub 2018 May 14.