I eat a LNCHFHF diet. That would be... a Low Net Carb, High Fiber, High Fat diet. I average between 30g & 50g of fiber per day. When I started eating low carb 4 years ago I was doing an Atkins like diet with the usual meat, eggs, dairy, and induction veggies. I kept net carbs < 30g and typically ate less than 10g of fiber. 9 months into the diet I started checking my BG. My FBG was still high (105 - 115). I learned at that time that I was also very reactive hypoglycemic. Testing my postprandial BG my evening LC meals (usually less than 12 net carbs) were still spiking my blood sugar well above 150. Some foods could even spike my BG over 200, followed by a rapid crash to below normal levels, generating the same intense carb cravings that I had eating the junky SAD diet.

So I was still deeply insulin resistant. It didn't take much glucose at all to send my BG up and down a rollercoaster after eating. That is when I really started reading up on the glycemic index of foods - how fast and hard different foods hit your blood sugar. Of course, the carbs are the real problem. Fat, meat, eggs, etc. have little effect on blood sugar. But my diet at that time included some carbs and through lots and lots of BG testing I was able to improve my BG response to the foods that I was eating. I tested my morning FBG, pre-dinner BG, and 4 times post dinner at 30 minute increments. I often tested again at bedtime. I did that several times a week for a couple of months. That's a lot of finger pricking. It was worth it, though. I learned a lot about how what I eat affects my BG.

Here is what I learned about myself during all that BG testing...

Mixing higher GI foods (like some of my cooked LC veggies) with low GI foods resulted in a slower and lower rise in BG.

Raw veggies affected my BG less than cooked veggies. Pureed veggies in soups (especially onions) would really spike my BG fast.

The order that I ate my foods mattered. If I started a meal off with a cup of 8 net carbs of soup my BG would spike higher than it would if I had the soup after the meat and raw veggies. I tested this by having the exact meal for consecutive dinners, eating the same quantity of food in a different order.

Having fiber before a meal ( 1 tbsp. psyillium powder in water -7g of fiber) tempered my BG response to the carbs I was eating. I'd get a slower rise and fall in BG from the same meal when I consumed fiber as my appetizer.

And finally, the most important thing that I learned from all of this was that when I have a low, slow rise and fall in BG after a meal I have lasting satiety. When my BG spikes and falls too quickly, then I get that 'raid the pantry' feeling and want to eat again much sooner.

Not long after I started doing all of this BG testing my insulin resistance suddenly improved. My fasting BG dropped into the 70's and 80's. My 10 to 15 net carb dinners wouldn't raise my BG higher than 100 most days. I was much less reactive hypoglycemic. So what I learned from this is that all of those things I listed above really mattered when I was highly insulin resistant. Now... not so much. When the insulin resistance was resolved I tolerated the carbs that I eat much better. I didn't need to be so careful. I didn't need to test my BG so often.

At about 1 year into this WOE I tweaked my diet, lowering the carbs to < 20 net (deep keto) in an attempt to keen the scale number moving down. It worked. But at my next annual checkup I found that my cholesterol had gone through the roof. My TC was well above 300 and my LDL-C was 248 - double what it had been the year before. I discovered that I was one of those 'hyper-responders' to VLC/Keto. Long story short, I found some advice for how to lower my cholesterol and wound up adding a lot of fiber to my diet. In addition to what I normally ate I started having more flax muffins, chia seeds, hemp hearts, and supplemented daily with psyillium powered. My typical day became 30 to 45 net carbs with often more grams of fiber than net carbs. I did that for the next 18 months, reaching and surpassing my goal weight. My cholesterol improved steadily the whole time.

So was the improved cholesterol due to thee fiber or was it simply me getting healthy? Well, one way to find out... Last winter I went full on deep-keto again (< 20 net carbs, dropping much of my fiber intake). My TC and LDL cholesterol shot up again. I also didn't seem to have the same level of satiety between meals eating VLC/low fiber as I did with my higher fiber, higher net carb diet. So now I'm back to eating they way I did during those last 18 months of my journey to goal. I seem to do OK (or better) having more fiber in my diet.

A few months ago I had my first ever colonoscopy. I had some blemishes and one polyp (which was removed). I was back on the VLC/Keto plan at the time. The doctor recommended a high fiber diet - calling it a 'colon cleanser', which is part of the reason I switched back to my higher fiber diet. Since I didn't have a clean result I will be having another colonoscopy in 5 years instead of 10. I don't if they are right about fiber being helpful. I don't know for sure if my high LDL cholesterol was a problem. I may or may not stick with my current WOE. I like mixing things up every once in a while. Only time will tell.

There is much talk about fiber, both for and against. I don't know if my high fiber diet is my optimal diet or not. What I do know is that I don't have a problem with it. It seems to work fine for me.


I found this to be true for me when I added a bunch of fiber to my daily routine (although I ended up with constipation rather than diarrhea). It was uncomfortable. When I added a daily flax muffin to my diet it felt like a lump of gravel working its way through my system and I did have more gas. However, this was all temporary. Whenever I make a significant change to my regular diet I go through a few weeks of adjustment. When I first went low carb I was seriously constipated for weeks. Then things normalized. When I transition from my high fiber diet back to VLC, the same thing happened. After a week or two of discomfort my body adjusts to what I am eating and I get regular again - whether my daily diet includes lots of fiber or does not.