Are Carbs Required by the Human Organism?

Photo by Polina Tankilevitch on

What exactly is a carbohydrate?



any of a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They contain hydrogen and oxygen in the same ratio as water (2:1) and typically can be broken down to release energy in the animal body.”water-soluble carbohydrates”

Definitions from Oxford Languages

Any way you look at it, a carbohydrate is a form of sugar, most of which are or quickly convert to glucose in the blood/body. So what’s wrong with glucose? Well, some have no problem processing glucose. Others may find much trouble with the consumption or processing of glucose such as those with hyperglycemia, diabetes, insulin resistance, heart disease, cancer, and those trying to maintain ketosis, etc. Glucose causes spikes in blood sugar, and therefore, insulin in response to glucose. While impossible for some to produce insulin or sufficiently as in diabetes, some develop problems processing glucose due to insulin resistance.

It makes sense then, that if no glucose is present the pancreas doesn’t have need to produce insulin to properly utilize the glucose or as much, and reduced risk of developing insulin resistance, obesity, diabetes, heart disease, etc. can be found. Many just can’t seem to grasp this. Claims that the brain, or body, or thyroid need glucose have been passed around for decades but is this true? Let’s see what some of the experts have to say about it.

Carbs and the Brain

Dr. Stephen Phinney M.D., PhD. says, 1

The belief that the brain and central nervous system need carbohydrates to function properly is often supported with the circular logic that the brain uses glucose therefore it needs glucose, and it needs it because it uses it. The hole in this argument is that the brain does not in fact need glucose. It actually functions quite well on ketones. Stating it another way, the presumed requirement for glucose by the brain is a conditional need that is based on the fuel sources dictated by one’s choice of diet. A ketone-suppressing diet (i.e., any diet supplying >30% of energy from the combined intakes of carbohydrate and protein) essentially forces the brain to rely on glucose for fuel. /”Physiological Role of Carbohydrates”

Studies have offered significant proof of normal brain function when glucose is not present, providing sufficient ketones (hydroxybutyrate (βOHB) and acetoacetate (AcAc)) are available. The unique perspective from this is that when one is consuming a carbohydrate-rich diet, the primary source of fuel for the brain is glucose; not because it is needed but because the other natural highly effective brain energy source has been shut off. When there is consistent nutritional ketosis, the brain adapts to ketones as fuel by increasing their uptake and oxidation, protecting normal cognitive function. 1 2 3 4 5

Dr. David Perlmutter, M.D., author of “Grain Brain” is another who says there is no human requirement for carbohydrates. In fact, he uses one whole page to say,

While we definitely require protein and fat, the human requirement for dietary carbohydrate is none, none whatsoever. – How much carbohydrate do we absolutely require in the diet?

Contributing writer for the Huffpost, Mike Sheridan, Nutrition & Fitness Expert, and author of Eat Meat And Stop Jogging, shares this,

The reality is, humans are not meant to consume an abundant amount of carbohydrates. Not only because our daily activity is less than the hunter-gatherer, but because there is:

No dietary requirement for carbohydrates! When and if our body is ever desperate for energy, it is perfectly capable of making its own glucose through gluconeogenesis. If absolutely necessary, we are fully capable of taking non-carbohydrate sources and creating carbohydrate structures.

Unlike protein and fat, carbohydrates supply none of the elements necessary to build or repair tissue in the body, and provide no essential component. – Mike Sheridan

In Michael Sheridan’s article, is a statement from the Institute of Medicine

“The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed.”

Institute of Medicine (IOM) 2002

Dr. Andreas Eenfeldt, also known and the Diet Doctor, is a Swedish medical doctor specialized in family medicine. He is also the author of the largest health blog in Sweden, as well as serving board of The Dietary Science Foundation. Dr. Eenfeldt believes firmly that little to no carbs are required by humans. In an interview with various other physicians, the following questions were asked about the brain needing carbohydrates.

Dr. Andreas Eenfeldt: The brain needs carbohydrates, otherwise it’s not going to work. Is it true?

Dr: Hallberg: Well, if you’re eating carbohydrates, the brain needs carbohydrates. But if you’re not eating carbohydrates, the brain is happy. And I think a lot of evidence would actually support “happier” to be using ketones as fuel.

Dr. Andreas Eenfeldt: People say that the brain needs carbohydrates. What do you think?

Dr. Fung: Yeah, that’s another one that’s completely false. Not completely false. You see, the best lies really have a grain of truth. And what they mean, is that the brain requires some glucose to function, but it doesn’t require you to eat glucose to function and that’s the distinction.

Another from Dr. Perlmutter, M.D.,

Carbohydrates, whether derived from gluten-containing foods or other sources, including fruit, sweetened beverages, and starchy vegetables, are dangerous as they relate to brain health in and of themselves.

David Perlmutter

Andre Obradovic, Certified PCC ICF Coach, and Founder of Which Path Coaching Pty LTD, responded to the following statement:

The author claims that carbohydrates “help to balance your energy levels” and justifies it by saying that low glycaemic index (GI) foods help achieve a “steady, stable stream of energy for two or more hours post consumption”. with this,

This is plainly wrong.

He added in another comment regarding carbs claiming that carbs are “essential for exercise performance“. responded with this,

One of the most enduring myths about carbohydrates is that they are “essential” in the diet. Even the most basic biochemistry book will tell you that dietary carbohydrate is not an essential macronutrient, unlike protein and fat.

Andre Obradovic –

Another claim is that high fiber carbohydrate foods promote bowel health. To this, Andre Obradovic says,

Closer analysis of the literature is leading doctors to think that the benefits of fiber have been oversold. For example, a well designed study showed that constipation, bloating, bleeding & pain significantly improved when people cut fiber from their diet.

Andre Obradovic –

Carbs and the Thyroid

Another claim is that the thyroid needs carbs. I hear this one almost as much as with the brain needing glucose. While there’s no debate over some people finding they’re thyroid hormone levels have changed when shifting to a low-carbohydrate lifestyle but there are many things that can factor into that. Eating fewer calories than one expends, causing weight loss, can encourage the reduction in thyroid function to slow its metabolism.

Dr. Phinney says this is not abnormal state for the thyroid since less is thyroid hormone T3 is needed:

When one is weight stable on a LCHF diet is that the body becomes more responsive to these hormones due to beneficial changes in cell structure and function when in nutritional ketosis. As a result, it can function normally at lower T3 levels. Put another way, a ketogenic diet seems to result in improved thyroid hormone sensitivity (i.e., it takes less hormone to produce the same effect), which, if anything, puts less of a burden on thyroid hormone (T4) production in the thyroid gland and its conversion to T3 in the liver. /Dr. Stephen Phinney M.D., PhD.

Dr. Sarah Hallberg on thyroid and low-carb responds to the question “Will Low Carb hurt my thyroid?” said,

It will not make a difference one way or the other.

Dr. Sarah Hallberg/

A statement made in an article of Woman’s World said in reference to carbs and the thyroid, “According to University of Michigan research, cutting calories to lose weight can send us into a thyroid-suppressing “starvation mode.” Luckily, on Atkins [or “Low Carb”] you’re not cutting calories, so you don’t stress your thyroid. Also key: The Italian team found that cutting carbs reduces autoimmune attacks on our thyroids.

Dr. Anna Cabeca on thyroid and low carbs said,

“There have been a number of studies showing that people with thyroid disorders actually feel better when on a low-carb diet! This is what I have seen with the participants in my program.

In a MyFitnessPal blog, “Can You Survive Without Carbs? | Ask The Dietitian” –

For decades, doctors and nutritionists prescribed low-fat diets to people trying to lower their risk of heart disease. Saturated fats in meats and dairy products were thought to clog our arteries. Grains — especially “whole” ones — were thought to help everything from high cholesterol to digestion.

A growing body of research suggests this advice was wrong. For most people, it’s carbohydrates, not fats, that are the true cause of heart disease.

Trinh Le, MPH, RD /

Trinh Le, while advocating some carbs as “okay” says,


Nutrition science defines a nutrient as “essential” if we must get it from the diet because our body can’t make enough of it to meet our needs. Deficiencies in protein, essential fats (linolenic and linoleic), vitamins and minerals all match up to an impairment or disease. This same phenomenon doesn’t exist with carbohydrates.

Ongoing studies and those pioneering the low-carb movement all agree, there is “NO” human requirement for carbohydrates. While some say they are needed, science has proven this to be false as has thousands of years of anecdotal evidence since some cultures have lived without carbs and have maintained optimal health in all areas through long periods of time.

A statement from Kent R. Rieske, B.Sc. of Bible Life Ministries said in an article on Carbs being

Carbohydrates displace essential protein and essential fats in the diet to cause a double health reversal. The carbohydrates themselves cause disease, and the deficiency of protein and fats contributes to or causes other diseases.

The consumption of carbohydrates generally begins showing the disease effects in either one of two directions.

*Body fat accumulation leads to obesity, diabetes, heart disease, cancer, gallbladder disease, degenerative bone diseases, cataracts, and many others.

*Damage to the intestinal tract leads to leaky gut syndrome, inflammatory bowel diseases, and a medical textbook listing of autoimmune diseases. These illnesses generally make the sufferer underweight and deficient in vitamins and minerals caused by poor digestion.

This articles goes on to say, “Carbohydrates drive insulin production, causing cardiovascular heart disease (CHD).

Eating a low-carbohydrate diet brings unhealthy body processes caused by insulin to a screeching halt. All humans react in the same way. People are not different from each another as the myth implies. The variable among people is the amount of damage already done to the body by carbohydrates and insulin. This damage is incorrectly diagnosed as genetic.

One last statement from Dr. Steven Sinatra

In the old days, when it came to carbs vs. fat, the thinking was that fat raised cholesterol levels, which then raised the risk of cardiovascular disease, heart attack, and stroke. So, doctors steered patients toward low-fat diets. That generally meant more carbohydrates.

The problem was that this thinking was all backward.

In other words, it is carbs we should be limiting, not fat.

It would appear there is more than enough evidence and support from many experts that carbs, while some may like them in their diet, are not a human requirement. Not only do we not require them, some say they can even be pathogenic and many of the above sources state excess carbs cause disease. 7

Professor Tim Noakes also gets in on this saying we not only don’t need carbs, but we don’t need vegetables. . . I’ll leave you with his half-hour video below.

Written by Douglas K. Johnson – Life, Health and Wellness Coach, Herbalist, Nutritionist, and Author

  1. Why Humans Don’t Need Dietary Carbohydrates to Thrive
  1. Alternate fuel utilization by the brain
  1. FAQ Keto: Ketogenic Diet
  1. Drenick, EJ., Alvarez, LC., Tamasi, GC., et al. Resistance to Symptomatic Insulin Reactions after Fasting. The Journal of Clinical Investigation. 1972;51:2757-2762
  1. Cahill GF Jr, Aoki TT. Alternate fuel utilization by the brain. In: Cerebral Metabolism and Neural Function. Janet V. Passonneau et al, Eds. Pages 234-242. Williams & Wilkins, Baltimore 1980.
  2. Does Your Thyroid Need Dietary Carbohydrates?
  1. Absolute Scientific Proof Carbohydrates Are Pathogenic
Medical Disclaimer

This blog/site pro­vides gen­eral infor­ma­tion and dis­cus­sion about med­i­cine, health and related sub­jects.  The words and other con­tent pro­vided in this blog, and in any linked mate­ri­als, are not intended and should not be con­strued as med­ical advice. 

If the reader or any other per­son has a med­ical con­cern, he or she should con­sult with an appropriately-licensed physi­cian or other health care worker.

Never dis­re­gard pro­fes­sional med­ical advice or delay in seek­ing it because of some­thing you have read on this blog or in any linked materials. If you think you may have a med­ical emer­gency, call your doc­tor or 911 immediately.

The views expressed on this blog and web­site have no rela­tion to those of any academic, hospital, practice or other insti­tu­tion with which the authors are affiliated.

Published by Douglas Johnson

I am a Life, Health and Wellness Coach, Herbalist, Nutritionist, Author & Chef

One thought on “Are Carbs Required by the Human Organism?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

Create your website at
Get started
%d bloggers like this: