Welcome to my first nutrient post! I’ve received tons of questions about fiber lately.
What is a good fiber supplement? Does it affect blood sugar levels? What’s the difference between soluble and insoluble fiber?
What is Fiber?
Fiber is a complex carbohydrate that passes through your intestine with little to no absorption.
There are two different types of fiber: soluble and insoluble.
Soluble fiber CAN be digested by the small intestine. It takes on a gel texture when mixed with moisture and helps your food glide through your intestine. It’s great for the lining of your gut and is known to help with keeping cholesterol and triglyceride levels low. Examples of soluble fiber are: oatmeal, nuts, beans, lentils, apples and blueberries.
Insoluble fiber cannot be digested by the small intestine and moves into the large intestine in a bulky form. What’s great about this fiber is that it can pass through your intestine more quickly, scraping the lining of the gut to help EVERYTHING pass through (toxins, etc). Examples include: brown rice, legumes, carrots, cucumbers and tomatoes.
Does Fiber influence blood sugar levels?
Ever have a sugar rush? Have you ever heard of the glycemic index scale? This scale is based on how quickly/high your blood sugar spikes after eating a specific carb. The amount of fiber within that carbohydrate will influence that GI rating. The lower the number the less of a spike occurs.
Here are some examples from a Harvard Health article:
FOOD | Glycemic index (glucose = 100) |
HIGH-CARBOHYDRATE FOODS | |
White wheat bread* | 75 ± 2 |
Whole wheat/whole meal bread | 74 ± 2 |
Specialty grain bread | 53 ± 2 |
Unleavened wheat bread | 70 ± 5 |
Wheat roti | 62 ± 3 |
Chapatti | 52 ± 4 |
Corn tortilla | 46 ± 4 |
White rice, boiled* | 73 ± 4 |
Brown rice, boiled | 68 ± 4 |
Barley | 28 ± 2 |
Sweet corn | 52 ± 5 |
Spaghetti, white | 49 ± 2 |
Spaghetti, whole meal | 48 ± 5 |
Rice noodles† | 53 ± 7 |
Udon noodles | 55 ± 7 |
Couscous† | 65 ± 4 |
BREAKFAST CEREALS | |
Cornflakes | 81 ± 6 |
Wheat flake biscuits | 69 ± 2 |
Porridge, rolled oats | 55 ± 2 |
Instant oat porridge | 79 ± 3 |
Rice porridge/congee | 78 ± 9 |
Millet porridge | 67 ± 5 |
Muesli | 57 ± 2 |
FRUIT AND FRUIT PRODUCTS | |
Apple, raw† | 36 ± 2 |
Orange, raw† | 43 ± 3 |
Banana, raw† | 51 ± 3 |
Pineapple, raw | 59 ± 8 |
Mango, raw† | 51 ± 5 |
Watermelon, raw | 76 ± 4 |
Dates, raw | 42 ± 4 |
Peaches, canned† | 43 ± 5 |
Strawberry jam/jelly | 49 ± 3 |
Apple juice | 41 ± 2 |
Orange juice | 50 ± 2 |
VEGETABLES | |
Potato, boiled | 78 ± 4 |
Potato, instant mash | 87 ± 3 |
Potato, french fries | 63 ± 5 |
Carrots, boiled | 39 ± 4 |
Sweet potato, boiled | 63 ± 6 |
Pumpkin, boiled | 64 ± 7 |
Plantain/green banana | 55 ± 6 |
Taro, boiled | 53 ± 2 |
Vegetable soup | 48 ± 5 |
DAIRY PRODUCTS AND ALTERNATIVES | |
Milk, full fat | 39 ± 3 |
Milk, skim | 37 ± 4 |
Ice cream | 51 ± 3 |
Yogurt, fruit | 41 ± 2 |
Soy milk | 34 ± 4 |
Rice milk | 86 ± 7 |
LEGUMES | |
Chickpeas | 28 ± 9 |
Kidney beans | 24 ± 4 |
Lentils | 32 ± 5 |
Soya beans | 16 ± 1 |
SNACK PRODUCTS | |
Chocolate | 40 ± 3 |
Popcorn | 65 ± 5 |
Potato crisps | 56 ± 3 |
Soft drink/soda | 59 ± 3 |
Rice crackers/crisps | 87 ± 2 |
SUGARS | |
Fructose | 15 ± 4 |
Sucrose | 65 ± 4 |
Glucose | 103 ± 3 |
Honey | 61 ± 3 |
Data are means ± SEM.* Low-GI varieties were also identified.† Average of all available data. |
Carbs DO effect your blood sugar, but some effect it MUCH LESS than others.
Fiber Supplement Recommendation

This is my absolute favorite fiber supplement. It has one ingredient – acacia fiber. When mixed with water, it is tasteless and for the most part dissolves if you add enough water. You need to stir it or it will clump together and form a gel-like substance (can you guess what kind of fiber this is?)
You can find more Renew life fiber supplements here.
Am I getting enough fiber?
Here’s the deal. Most processed foods have little to no fiber. They are stripped of nutrients and the flour that makes up products like crackers, most breads, pancake mixes, processed rice, out-of-the-box cereals have been processed so much that they have no complexity – no fiber. This means they will cause a blood sugar spike (before even accounting for how much sugar is added in these things). In the end, you’ll be hungry in an hour. Especially if you didn’t pair it with a fat and protein source – which are both really satiating.

If you are consuming fruits, veggies, WHOLE GRAINS like quinoa or real oats and meat/fish/poultry then you absolutely are eating enough. KEEP IT UP!
If you have more questions about fiber, where to find it, how to make it taste good or other supplements you’ve found – HIT ME UP!
Thanks for reading xo
Crystal Dee
Sources:
Carbohydrates and Blood Sugar – Harvard Health
Lattimer JM, Haub MD. Effects of dietary fiber and its components on metabolic health. Nutrients. 2010;2(12):1266–1289. doi:10.3390/nu2121266
Glycemic Index for 60+ Foods – Harvard Health