First let me give you a definition of essential:
For something to be essential to the diet it must have a clear and measurable disease associated with the absence of it.
There has not been a single study that conclusively shows that a deficiency in fiber exists. There are however, many societies of people who eat little to no fiber and thrive with none of the diseases of the western societies that do eat fiber.
The Inuit of northern Canada, the Inuit of northern Greenland, The native diet of the Scandinavian, the Masai, the San Bushmen of the Kalahari, the Nenets of Siberia and the list goes on. All of these tribes of people live disease free and long lives despite living in some of the world’s harshest climates and in the near complete absence of dietary fiber. Only when high carbohydrate and yes, high fiber foods of the western culture are introduced to these tribes do they develop the diseases of lifestyle. I myself have not had more than a few grams of fiber per day in the last 10-13 years. I am in perfect health and lead a very active lifestyle.
By Definition, Fiber is not essential to the human diet just as carbohydrate is not essential.
I am not saying that fiber causes any of these diseases. I am saying that the absence of fiber does not have any detrimental effects. Fiber can in fact be very useful in some instances. In this article I will lay out the benefits and detriments of fiber and who can benefit from it and who should avoid it.
Fiber is very good at regulating the rise of blood sugar. This is of great benefit to diabetics. Especially with type 1 diabetics whose primary concern is keeping blood sugar low. It is also useful for type 2 diabetics who wish to eat their carbs.
For weight loss it is actually counter productive and I will tell you why.
The way that fiber acts to regulate blood sugar is through its ability to slow gastric emptying (slowed emptying of the stomach). This slows glucose rise because the slower the food is released from the stomach, the less glucose is released into the blood and therefore the slower and more consistent the rise would be. Again, great for people concerned with controlling high blood sugar spikes. Not at all useful for someone trying to lose weight.
For weight loss we want longer periods of lowered insulin. When we eat fiber it prolongs the release of the glucose but it still gets released and it still has to be dealt with. The only thing that can deal with glucose is insulin. Essentially it changes the response from one higher insulin release that deals with the glucose and leaves the system to a long drawn out slow release with a corresponding drawn out insulin flow to regulate. We always have a base of insulin flow. It is not this low baseline that is of concern because at baseline, glucagon will be higher and will act to push fat from cells to be used as energy. If you look at the chart you will see that as soon as glucose rises, no matter how much, insulin is released. The more glucose the more the insulin but regardless, even a small increase in blood glucose results in a rise in serum insulin above baseline and any rise above baseline stops lipolysis (the release of fat). You can see this in both the optimal insulin balance chart and the poor insulin balance chart that the near instant that blood glucose rises that insulin rises in direct response to it.

Wha do you want? One quick release then back to a low base of insulin or a long drawn out response that keeps fat locked up longer? Adding lots of fiber to a meal is essentially like grazing constantly and this is known to be bad for weight loss.
Grazing causes weight regain in bariatric patients
The effects of glucose management with fiber and how it is done through gastric emptying is not new. This is a well known fact and it completely explains why eating fiber is thought to be beneficial to weight loss. The only problem is, we need to stop associating blood glucose control to weight loss. The two are mutually exclusive of one another. You can have completely normal, low and stable blood glucose numbers but if you have chronically elevated insulin you will never lose a pound.
The impact of soluble dietary fibre on gastric emptying, postprandial blood glucose and insulin in patients with type 2 diabetes
Common Fiber misconceptions:
1. You need fiber to have proper bowel movements.
That depends on what you consider proper? Does going 1-2 times a day mean proper? Well I eat zero fiber and I have some days where I go 3-4 times. It all depends on how much food I’ve eaten. If I eat alot of food I go more often. If I eat less food I go less often but in general I go once a day at least. Does proper mean of good consistency? Well again, I eat no fiber and the consistency of my poo is pretty normal. Do I have days where it is less than normal? Of course but that depends on what I have eaten that day. If I eat higher than 90% fat for the day it will be more loose. If I eat closer to 80-85% it is more consistent. There are days when those that eat fiber have less than perfect poo.
What we have to keep in mind is that meat and fat is 90-95% digested and used by the body. Plant matter is only 20-60% digested by the body. Of course if we eat alot of food that does not digest we are going to go more often. Why does going more often mean you are more healthy. Poo is a way of getting rid of garbage. Wouldn’t going less often mean you have less garbage to get rid of? Makes sense to me.
2. Fiber feeds the gut bacteria.
Yes it does. But why is this important? Feeding the gut bacteria causes these gut bugs to produce vitamins. Great but the whole reason we need these vitamins from the bugs is because fiber actually binds to and blocks the absorption of these vitamins from our food thus creating the need for these gut bugs to eat the fiber and produce more of them. Why not just lose the fiber and use the perfectly bio available source of these nutrients from the food we have eaten. Why do we need to feed ourselves plus have to worry about supporting another species in our guts. Again, seems logical to me just to get the nutrients from good food.
Dietary Fibre and absorption of Nutrients
3. Eating lots of fiber and leafy greens can help you feel fuller longer and help you lose weight.
Yes it can but not long term and will actually cause you to stall faster and make weight gain much easier. The reason fiber and plants help you feel full faster and longer is two fold. They take up alot of space with very few calories and the fiber slows the emptying of the stomach so you feel fuller longer. How is this going to make you stall? This is just another method of caloric restriction. A trick to get you to eat less. Sure you feel full but you are getting very little in the way of actual nutrition. You are getting maximum fullness with minimal energy content. The goal of nutrition is not too feel full. It is to get the energy and nutrients you need in order for you body to make all the biochemical reactions necessary to create the enzymes and hormones that create energy for your body and nourish it with vitamins and minerals. If your only goal is to get full, drink 4 gallons of water at every meal. You will be full and get the very least amount of calories possible. You will also die of malnutrition. I’ve heard this before as well by the way.
Increase water intake to reduce caloric intake or The best way to become nutrient deficient
So this is yet another trick to get you to eat less and cut calories when we know all this will do is leave you tired, malnourished and have you stalled in no time. Once you stall are you going to want to keep eating 20lbs of lettuce a day with no weight loss to show for it? Of course not. You will quit, eat a cake and gain the weight back. Nice try CICOpaths but we know better.
I hope this sheds some light onto how fiber affects people differently.
Keto ON!
Coach Jack
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