Could Acellular Carbohydrates Be the Cause of Obesity?

Ivor Goodbody in a recent tweet reminded me of an interesting nutrition science article.  Ian Spreadbury hypothesizes that carbohydrate density of modern foods may be the cause of obesity.  Refined sugars and grains—types of acellular carbohydrates—are  particularly bad offenders.

Harvesting acellular carbs

These acellular carbs may alter our gut microorganisms, leading to systemic inflammation and leptin resistance, etc.  Our Paleolithic ancestors had little access to acellular carbohydrates.

Read more about it in “Comparison with ancestral diets suggests dense acellular carbohydrates promote an inflammatory microbiota, and may be the primary dietary cause of leptin resistance and obesity,” in Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy, 2012, vol. 5, pp. 175-189.

To reverse our modern obesity epidemic, we need better understanding of the underlying pathophysiology.


PS:  For Spreadbury’s formal definition of acellular carbohydrates, see my long comment below.

12 responses to “Could Acellular Carbohydrates Be the Cause of Obesity?

  1. Several issues to consider here: researchers must rule out GMO as a contributing factor, since most food, feed crop in the USA is GMO. Because the USA has exported the westernized diet along with fast food franchises, sodas, etc.. to other countries, it’s impossible to rule out that GMO is not being ingested by countries that do not permit the growing of GMO crops.

    Second, there is an important need to identify the specific temporal sequence of events. Most studies show that an obesity/energy storage related inflammatory response (originating in adipose tissue) contributes to the sequelae of protein products that are secreted and released by adipose tissue, as a result of enlarged/engorged adipocytes – which represents a positive energy balance, compared to say, a high number of adipocytes all within healthy size ranges.

    A high level of adipose cellularity (number of fat cells) does not elicit the same physiologic response. These numerous regulatory proteins (also known as adipokines) that are secreted by large adipocytes are autocrine, paracrine, and endocrine in nature, essentially it IS feedback physiology to constrain continuing energy uptake – glut 4 is decreased, insulin receptor and signaling decreases, LPL decreases, etc…Most of this stuff normalizes with adequate weight loss and freeing up storage space of the adipocyte.

    Finally, circulating IL-6 – an inflammatory cytokine, predominately derives from adipose tissue and acts on the liver to secrete C-reactive protein (CRP) which is a marker for systemic inflammation.

    I am not arguing the important potential contribution of energy dense, GMO crop such as corn and its’ derivatives, soy and its’ derivatives, and other GM crop – beet, etc… GMO just needs to be ruled out as the instigator of unfavorable gut alterations. If or when GMO can be ruled out, then it will be very easy to test your hypothesis.

    Great post!

    • Coop Poop, thanks for your contribution. I bet the GMO contribution, if any, could be tested pretty easily by a motivated bench researcher with funding. Archer Daniels Midland probably won’t fund it. I think some ancestral wheat strains are still around (is it Eikhorn?).


  2. What I like about Spreadbury’s hypothesis is that he ties together food quality – carb quality – with the hygiene hypothesis. He creates a good working model for a “safe starches” exemption.
    Food in New Zealand is NOT GMO, no fast food franchise would dare sell it, yet we have the same health issues as the USA. It is associated with corn, wheat, sugar and seed oils – but they are not GMO, and most red meat used is locally grown and not GMO fed.

    • About “safe starches”:
      Paul Jaminet lists rice and potatoes among his safe starches.

      Spreadbury would consider potatoes to be acellular carbohydrates, therefore “safe” in Jaminet’s world. I don’t know for sure how Spreadbury would characterize rice; I bet rice flour would be acellular, if only because of grinding/pulverization. I saw no mention of rice specifically, except in a list of non-paleo foods. Rice does have relatively low carbohydrate density, which Spreadbury likes in general. On the other hand, rice is a grain and Spreadbury worries about refined grains and their high carb density.

      Here’s how Spreadbury defines acellular carbohydrates:
      “Foods that would be permitted on a Paleolithic or “primal” diet – the “ancestral foods” – are those in the categories of root tubers, leafy vegetables, fruit, nuts, meats, eggs, and fish, and are shown in white. Tubers, fruits, or functional plant parts such as leaves and stems store their carbohydrates in organelles as part of fiber-walled living cells. These are thought to remain largely intact during cooking, which instead mostly breaks cell-to-cell adhesion. This cellular storage appears to mandate a maximum density of around 23% non-fibrous carbohydrate by mass, the bulk of the cellular weight being made up of water. The acellular carbohydrates of flour, sugar and processed plant-starch products are considerably more dense. Grains themselves are also highly dense, dry stores of starch designed for rapid macroscopic enzymic mobilization during germination. Whereas foods with living cells will have their low carbohydrate density “locked in” until their cell walls are breached by digestive processes, the chyme produced after consumption of acellular flour and sugar-based foods is thus suggested to have a higher carbohydrate concentration than almost anything the microbiota of the upper GI tract from mouth to small bowel would have encountered during our coevolution. This may stimulate differing bacterial species to prosper or be outcompeted, or increase some microbial metabolic pathways and waste products in preference to others. It is proposed that the effects of these enhanced carbohydrate concentrations will include a more inflammatory GI microbiota, initially causing leptin resistance, hence the greatly elevated leptin levels seen in Western populations when compared to those eating a wholly cellular diet.”


      • There are two places in this response where I think you mean “cellular” not “acellular” – not to be a PITA, but this is new info, easy for misconceptions to be laid down on first reading….
        1 “potatoes to be acellular carbohydrates”
        2 “Spreadbury defines acellular carbohydrates”

  3. George:

    “While the GMO ban will curb the planting and importation of GMOs in the country, a test conducted by the Peruvian Association of Consumers and Users (ASPEC) at the time of the ban’s implementation found that 77 percent of supermarket products tested contained GM contaminants.”

    This was a shocking reminder that although a country might ban the planting and importation of GMO’s per se, global multinational mega-corporations are probably using GMO as the source of ingredients. If a packaged food product has the ingredient of corn, soy, canola, beet sugar, and/or any derivative thereof, it’s probably GMO.

    I think a nice well designed study could definitively rule out GMO’s. An important step too, would be to also control for energy intake.

  4. Like this RCT:
    Low-fat versus low-carbohydrate weight reduction diets: effects on weight loss, insulin resistance, and cardiovascular risk: a randomized control trial.

      • Steve:

        Thank you very much for your reasonableness, You would be astounded at how many people become really irritated at anything that questions their personal stand on a subject.

        I believe all good scholars and scientists should to the greatest degree possible, try to refute or at least try to poke holes in their own hypotheses. That often means actively searching for or at least considering plausible alternative explanations and not being too attached to any particular theory. It’s hard to remain curious and unbiased, for sure. The science is never really settled though, is it?

        And, we all must remember to differentiate between epidemiological (population) data and the individual. Everybody IS different and responds differently on innumerable levels.

        As for me personally? The paleo-diet certainly “works” for me! I avoid corn, soy, rice based products to a great degree. Wheat, however, does not bother me, nor does a bit of potato along with oats and other natural grains.

        Years ago, I did some blood work after eating a regular “balanced” diet and then I went on the Atkins diet — full on high saturated fat (not really the paleo-diet which allows for carbohydrate from vegetables and fruit.) I lost some weight on Atkins (relatively speaking, as I was athletic to begin with) and my blood work afterwards was great. Saturated fat did not adversely affect my lipid panel at all. But, research has shown that trans fatty acids might be the real culprit. However, there were other aspects to the Atkins diet that did not work for me to the degree that I would maintain it long term within my lifestyle. In a nutshell, I like to cycle particular diets to optimize and satisfy my interest, motivation, and palette.

        Thanks again for providing a most interesting forum!
        My blog, btw, is entirely personal – not professional.

  5. The acellular consideration raises some interesting points. The GMO issue is, in dietary terms, a red herring, undoubtedly proposed because that herring is someone’s pet.

    The initial problem here is that probably there is not just one thing “causes” obesity. First of all “cause” is a lot like proof and truth in its significance and difficulty. Thus trying to establish “cause” takes the discussion in an odd, and fruitless, direction. Second, obesity seems to relate to several matters (or insults), and the body can only cope well enough with one or two at a time. Thus the wheat issue and vegetable oil interference with cell signaling for hunger, combined with acellular carbohydrates, and fructose… leads to obesity. Trying to pin this down to one issue is.. fruitless.

    And it is unnecessary. It is simple enough to avoid all the reasonably certain triggers for obesity: Do not eat more than trivial amounts of wheat, which would mean avoiding most of the acellular stuff, like wheat flour. And it eliminates dwarf wheat. Minimize carbohydrates of all types. Do not eat vegetable or seed (PUFA) oil: it is not a food. Eliminate sweet sugars from your diet: your body can make all the glucose it needs. Sugar may not be evil, but it certainly is another carbohydrate. Eat fat and meat and vegetables, mostly. Eat fruits, but do not drink fruit juices: nature did not intend people to have fruit juices, and the juice is, obviously, both high in fructose and acellular. Eat enough choline rich foods. Get enough Vitamin D and K2.

    Embrace periods of hunger, because it makes your body switch to using stored fat.

    Something is wrong if a factory made the food. It is not a good sign at all.

    • Richard, you pretty well describe the paleo diet. Only left out nuts/seeds, which should be OK in moderation. (Beware: cashews are one of the highest-carb nuts. And you get too many omega-6 fats if you eat too many nuts. Cordain would not be happy.)


  6. Richard:
    “The GMO issue is, in dietary terms, a red herring, undoubtedly proposed because that herring is someone’s pet.”

    GMO just needs to be ruled out – that’s all. No red herring.

    “Embrace periods of hunger, because it makes your body switch to using stored fat. Something is wrong if a factory made the food. It is not a good sign at all.”

    Succinct and beautifully said!