On Friday afternoon, I was working at one of my favourite local cafes in Leslieville Toronto and getting ready to wrap up my week of work. Just as I was about to close my computer, I got a call from CTV News requesting an interview that evening.
The topic they wanted to me to cover was…Fiber.
Specifically, in response to this study released last week…
How much fiber do we need?
We are told again and again, that we need to eat MORE fiber. But how much?
- 38 grams of fiber for men
- 25 grams of fiber for women
- 19 grams for children aged 1-3 years old
- 25 grams for children aged 4-8 years old
As we get into the teenage years, girls need about 26 grams. While older/teen boys should get 31 grams to 38 grams per day.
But we’re not getting enough…
- On average, men consume 21 grams per day (vs. 38 grams required).
- And women are only getting 17 grams per day (vs. 25 grams required).
- Our little humans are also falling short. For instance, the average fiber intake for children between 3 and 5 years of age is about 11 grams per day.
.TAKEAWAY – No one, regardless of gender or age group, is getting sufficient fiber according to the IOM’s standards.
Fiber 101: A closer look at what fiber actually is (and does)
- INSOLUBLE FIBER (a dietary fiber found in whole food)
- SOLUBLE FIBER (a dietary fiber found in whole food)
- FUNCTIONAL FIBER (a manufactured fiber, or extracted and isolate from whole foods)
- Some say it acts as a laxative, preventing constipation (but keep reading!).
Examples of insoluble fiber: parts of plant cell walls, like cellulose
Soluble fiber on the other hand, attracts water like a sponge and turns into a gel-like substance. It slooooows down digestion keeping us fuller longer. Unlike insoluble fibers (which pass through the digestive system unaltered), naturally occurring soluble fibers are fermented by the bacteria found within the digestive tract.
- Fermentation generates essential nutrients for survival/growth of gut bacteria
- Reduces appetite
- Improves blood sugar sensitivity
- Lowers cholesterol
- Prevents cancer
- Balance hormone levels
- Remove excess estrogen and reduces the risk of breast cancer
- Makes vitamins and minerals
Functional Fiber is an isolated, non-digestible (insoluble) form of carbohydrate extracted from whole foods – or manufactured – and added to prepared foods to boost its fiber nutrition.
Packaged products are using functional fibers as a way to reach 3 grams – which is the minimum amount required to have the words “good source of fiber” on the label. Yet in comparison to a whole food, it’s not..
Here’s are some of the common highest fiber whole foods.
- Half an avocado (6 grams)
- Medium artichoke (10 grams)
- One cup of raspberries (8 grams)
- One cup sweet potato or winter squash (6 grams)
- Apple with peel (5 grams)
The challenge with “functional fiber” found in products like high fiber cereal bars, is that it can be more upsetting to your gastrointestinal system than naturally occurring dietary fiber (from whole foods). And as you’ll see below, fiber binds to critical nutrients (like iron), ushering them out of our bodies. So instead of taking a fiber supplement which is void of nutrients, eating whole foods is a better choice because it replaces lost minerals.
Have you heard about this gem called “resistant starch” yet?
- Improves digestive health
- Enhances insulin sensitivity
- Lowers blood sugar levels
- Significantly reduces appetite
Yuriel Kaim calls them “super starches”. Here’s why:
To thrive, your large intestine and the bacteria within it must have proper fuel. Short-chain fatty acids—especially one called butyrate —are the preferred fuel. To make butyrate, the large intestine needs starch. But most starch is broken down in the small intestine. So resistant starch moves past the small intestine and into the large intestine…and is one of the sources of butyrate.
Examples of Resistant Starch:
- Green (unripe) bananas
- Properly prepared cooked and cooled parboiled rice or legumes
- Cooked and cooled potatoes
Why should we feed our families fiber?
- A 15% to 30% reduced risk of death and chronic diseases
- A 22% reduced risk of stroke
- A 16% lower risk of Type 2 diabetes and colorectal cancer (although this is up for debate – see below)
- A 30% reduced risk of death from coronary heart disease
But wait! Fiber isn’t always the answer
Many parents worry about their child’s intake of fiber, and rightly so. However, you should know that fiber is not the perfect nutrient for everyone. In fact, it’s considered an “anti-nutrient”…
Here are some of the downsides of fiber:
Slower transit time
Limited absorption of key nutrients
According to a study in the Journal of Gastroenterology:
The main feature of a high-fiber diet is its poor digestibility.
No effect on colorectal cancer
Troublesome for those with chronic constipation.
To quote the same study above:
Although stool frequency may be increased by the mass effect of fiber packing in the colon in normal individuals, this is not so in individuals who are chronically constipated.
The Bottom Line: The best way to feed your family fiber
Focus on dietary fiber from whole food plant sources.
Ideally limit “functional fiber” intake from fiber-fortified cereals or other packaged products which are isolated from whole foods (or manufactured).
Don’t toss the peel!
Majority of the fiber is stored in the outer peel of the fruit. For example, a medium apple with the peel contains ~4.5 grams of fiber. However, take that peel away and you’re only looking at 2 grams!
Opt for smoothies over juice.
Fiber is retained and blood sugar is controlled.
Re-consider fiber intake if chronically constipated.
If you or your child already eat plenty of fiber and the constipation is caused by something else, then adding more fiber may not help and could even make the problem worse [source]. Look at stress, irritable bowel syndrome (IBS), food intolerances, liquid intake, etc.
As long as you are feeding your family a variety of whole plant foods, fiber intake should take care of itself.
As for that CTV interview, we ended up getting pulled from the schedule due to ‘breaking news’ that night. So even if you didn’t hear it from me on TV you’ve got it all here. 🙂