Fibre is often immensely under-appreciated. It sits somewhere between a micro-nutrient (vitamins & minerals) and a macro-nutrient (carbs, protein, fat). There are generally two kinds of fibre, soluble and insoluble. Soluble fibre mixes into a gel in water (like the psyllium husk in Metamucil), and offers about 2kcal per gram of energy to the body (about 1/2 the energy of non-fibre carbohydrates). Insoluble fibre doesn’t mix with water, offers almost zero energy to the body as it’s generally not absorbed, and is more commonly referred to as “roughage”.
Both kinds of fibre are very important to have in your diet. I follow a “flexible dieting” or “If It Fits Your Macros (IIFYM)” approach to my diet. I eat mostly whole-foods, but eat anything I want as long as it fits into my daily calorie and macro targets. I also consider fibre my fourth macronutrient; it’s just important to me to meet my daily fibre intake target as it is to meet my daily protein intake. Actually, it’s probably even more important than protein.
There’s all kinds of experimental evidence supporting the long-term micronutrient benefits of fibre. Superior cholesterol, improved insulin sensitivity, and many others. But these are more long-term, generally small, accumulative benefits. Fibre also offers shorter-term, but much more profound macro-benefits as well;
- Fibre slows digestion, giving the body more time to absorb the nutrients in your food
- Fibre evens-out spikes of blood sugar levels, which can help to reduce hunger and improve diet adherence
- Fibre gives you swiss-clock regular bowl movements (not to mention making them magical)
- Fibre makes you feel “fuller” longer, helping you when you’re eating at a deficit
There is such a thing as too much fibre though. It’s common for us to think “If a little of something is good, a LOT of something must be even better!”; this is rarely true. Everything is only “good” in the appropriate context. If you eat too much fibre it can start to diminish the body’s ability to absorb nutrients as they become engulfed inside a barrier of fibre.
How much you should be eating depends on your diet, but I’ve set my daily intake between 0.15g and 0.3g per pound of bodyweight (~25-50g), scaled with my food intake.
Do you know how much daily fibre you’re getting? I track my daily fibre intake along with my fat, protein, and carb intake. It’s never been easier to track calories now that we have tools like myfitnesspal and their smartphone apps.
What’s the best form of fibre?
In my opinion the fibre in fresh, non-starchy fruits & veggies is best. But this is more about hitting multiple birds with one stone, getting both the fibre and micronutrients I need rather than the fibre itself being superior. Fibre is fibre. When I don’t get the fibre I need from the whole-foods I eat, I supplement with 1-4 tbsp of dry psyllium husk mixed well in water. You can get it at Bulk Barn for about $15/kg.