Carbohydrates, Essential Nutrients, and Official Dietary Guidelines

“You’ll be reassured to know that you don’t have to eat carbohydrates to live. It’s not an essential nutrient.
“It’s one of the first things we learn in nutrition is what does the body not make and what you HAVE to eat.
“You won’t find carbohydrate on this list.”
~Eric Westman, There’s no such thing as an essential carbohydrate

“Carbohydrates are not essential nutrients.”
~Denise R. Ferrier, Biochemistry

“Carbohydrates are not essential nutrients.”
~Simon W. Walker, Peter Rae, Peter Ashby, & Geoffrey Beckett, Clinical Biochemistry

“Carbohydrates are not considered essential.”
~Carie Ann Braun & Cindy Miller Anderson, Pathophysiology: Functional Alterations in Human Health

“No specific carbohydrates have been identified as dietary requirements.”
~Michael Lieberman, Allan D. Marks, & Alisa Peet , Marks’ Basic Medical Biochemistry: A Clinical Approach

“In the absence of dietary carbohydrate, the body is able to synthesize glucose from lactic acid, certain amino acids and glycerol via gluconeogenesis.”
~Jim Mann & A. Stewart Truswell, Essentials of Human Nutrition

“Even when a person is completely fasting (religious reasons, medically supervised, etc.) the 130 g / day of glucose needed by the brain is made from endogenous protein and fat.
“When people are “fasting” the 12 hour period from the end of supper the night before until breakfast (“break the fast”) the next day, their brain is supplied with essential glucose! Otherwise, sleeping could be dangerous.”
~Joy Kiddie, How Much Carbohydrate is Essential in the Diet?

Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids
from National Academies of Sciences, Engineering, and Medicine
published by Institutes of Medicine
2005 textbook of the US Food and Nutrition Board

The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed. However, the amount of dietary carbohydrate that provides for optimal health in humans is unknown. There are traditional populations that ingested a high fat, high protein diet containing only a minimal amount of carbohydrate for extended periods of time (Masai), and in some cases for a lifetime after infancy (Alaska and Greenland Natives, Inuits, and Pampas indigenous people) (Du Bois, 1928; Heinbecker, 1928). There was no apparent effect on health or longevity. Caucasians eating an essentially carbohydrate-free diet, resembling that of Greenland natives for a year tolerated the diet quite well. However, a detailed modern comparison with populations ingesting the majority of food energy as carbohydrate has never been done.

Why Won’t We Tell Diabetics the Truth?
by Diana Rodgers

They base the carbohydrate requirement of 87g-112 grams per day on the amount of glucose needed to avoid ketosis. They arrived at the number 100g/day to be “the amount sufficient to fuel the central nervous system without having to rely on a partial replacement of glucose by ketoacid,” and then they later say that “it should be recognized that the brain can still receive enough glucose from the metabolism of the glycerol component of fat and from the gluconeogenic amino acids in protein when a very low carbohydrate diet is consumed.” (Meaning, ketosis is NO BIG DEALIn fact, it’s actually a good thing and is not the same as diabetic ketoacidosis that type 1 diabetics and insulin dependent type 2 diabetics can get.) The RDA of 130g/day was computed by using a CV of 15% based on the variation in brain glucose utilization and doubling it, therefore the the RDA (recommended daily allowance) for carbohydrate is 130% of the EAR (estimated average requirement).

Added sugars drive nutrient and energy deficit in obesity: a new paradigm
by James J DiNicolantonio and Amy Berger

Mankind has survived without isolated, refined sugar for almost 2.6 million years.48 The body—in particular, the brain—has been thought to require upwards of 200 g of glucose per day, leading to the often cited dogma that glucose is ‘essential for life’.1 While it is true that glucose is essential for sustaining life, there is no requirement for dietary glucose, as fatty acids can be turned into brain-fuelling ketone bodies, and amino acids and glycerol are gluconeogenic substrates.49 Indeed, in the relative absence of dietary glucose, ketone bodies may supply upwards of 75% of the brain’s required energy, with the remainder supplied by gluconeogenesis provided by amino acids (from dietary protein or catabolism of body proteins) and from glycerol (provided by the breakdown of triglycerides in adipose tissue).33 Thus, exogenous glucose (eg, from added sugars) is not essential for sustaining life in humans, and in most people, restricting dietary carbohydrates seems to produce no ill effects.49 In fact, according to the Food and Nutrition Board of the Institute of Medicine of the US National Academies of Sciences, ‘The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed’.50

Administration of fructose or sucrose in humans has been shown to cause each of the abnormalities that define the metabolic syndrome (eg, elevated triglycerides, low high-density lipoprotein, insulin resistance, glucose intolerance, elevated blood glucose, elevated blood pressure and weight gain (specifically around the abdomen)),30 51–55 as well as features found in patients with coronary heart disease (eg, increased platelet adhesiveness and hyperinsulinaemia),56 57 all of which can be reversed entirely upon reverting to a diet low in sugar.47 52 56 58–60 Consumption of added sugars at current levels of intake is proposed as a contributing factor in a multitude of other diseases associated with early mortality, such as cardiometabolic disease,61–64 obesity,30 61 65–68 β-cell dysfunction and type 2 diabetes,6 20 69–71 hypertension,51 64 72 non-alcoholic fatty liver7 and atherosclerosis.6 73 74 Because of this, added sugars cannot be considered food.

What to Eat: The Ten Things You Really Need to Know to Eat Well and Be Healthy
by Luise Light, pp. 18-21, 

The alterations that were made to the new guide would be disastrous, I told my boss, the agency director. These changes would undermine the nutritional quality of eating patterns and increase risks for obesity and diabetes, among other diseases. No one needs that much bread and cereal in a day unless they are longshoremen or football players, and it would be unhealthy for the rest of us, especially people who are sedentary or genetically prone to obesity and diabetes. […]

At stake here, I told him, was nothing short of the credibility and integrity of the USDA as a source of reliable nutrition information. Over my objections, the alterations were included and the guide was finalized. I was told this was done in order to keep the lid on the costs of the food stamp program. Fruits and vegetables were expensive, much more expensive than breads and cereals, and the added servings of grains would, to some extent, offset the loss of nutrients from fruits and vegetables, the head of our division told me. However, the logic of that rationale escaped me.

Refined wheat products are what we called in the nutrition trade “cheap carbos,” stomach-filling food preferred when other, higher quality foods are unavailable or not affordable. They do little—if anything—to boost the nutritional quality of people’s diets and tend to add not only starch, but also fat and sugar to the diet. It was curious that there had been no discussion of the cost constraints of the food stamp program in any previous discussion over the many months we had been working on the guide. Intuitively, I knew I was being “played,” but other than stalling and requesting additional outside reviews I felt stymied.

Later, I remembered a Pan American Health Organization (PAHO) nutrition survey I had participated in during graduate school. One of our findings was a high rate of obesity among women in a particular region of the Caribbean country we were working in that had the lowest employment and per capita income. It puzzled me that the poorest region would have the most obese people until one of the physicians on our team explained that the prevalence of obesity was consistent with what he called an “impoverished diet,” too little nutritious food that caused people to feel hungry all the time, and with only cheap carbohydrates available to them, their hunger was never appeased, so they ate and ate and became fatter and fatter.

Was this inflated grain recommendation, I wondered, setting us up for a third world obesity scenario in our own country? Historically, the food guide was used to calculate the cost basis of the food stamps program. Did that mean we needed to develop two different sets of standards for nutrition, one for poor people and another for those better off, or did it mean that what was affordable in the food stamps program would determine what was best for the rest of us? Neither of these Hobson’s choices could be justified on scientific or ethical grounds. The changes that were made to the guide meant that any food product containing wheat flour, from white bread, Twinkies, Oreos, and bagels to pop toasters and Reese’s Puffs, would be considered nutritionally equivalent, which was not the case.

With my protests falling on deaf ears, the serving suggestions in the revised guide were incorporated into the regulations for the food stamps program, as well as the school breakfast and lunch, day care, and all other feeding programs administered by the USDA. Later, Congress set the serving amounts into legislative “stone” so it would be against the law not to serve the expanded number of grain servings that were in the new guide, a change that meant a financial windfall for the wheat industry. The new rules for school lunch programs increased the amount of bread and cereal products purchased for the program by 80 percent. For children in grades K through six, it meant eight daily servings of breads, cereals, and pasta, and for grades seven through twelve, ten servings.

For wheat growers, this meant an increase of 15 million bushels of wheat sold annually worth about $50 million and a retail sales boost of $350 million from additional sales of cereals, breads, and snacks. That didn’t include the extra sales resulting from the government subsidized food stamps program or revenues from the industry’s own efforts to shift public consumption toward more bread, pasta, and baked goods because of the new recommendations. Throughout the nineties, Americans increased their consumption of refined grain products from record lows in the 1970s to the six to eleven servings suggested in the new guide.

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Partial credit for some of the quoted material goes to Bill Murrin, from comments he left at the article Dietary guidelines shouldn’t be this controversial; published at Marion Nestle’s website, Food Politics.