For people learning about the now famous low-carbohydrate Paleolithic Diet, the sheer amount of information available may be overwhelming. For those who want to begin as quickly as possible, it may be beneficial to have a simplified list of the foods to avoid, as well as the reasons to avoid these foods. With this easy categorization of information, these people will be able to buy food with greater ease, as opposed to memorizing a long list of accepted foods.
A Short Introduction of the Paleo Diet
There are three general mindsets behind the Paleo Diet. The first is rooted in anthropology and/or evolutionary biology, depending on the scientist’s approach: Our Paleolithic ancestors were hunter-gatherers and ate hunter-gatherer foods. We are biologically identical to our ancestors; so eating the foods these ancestors consumed is more conducive to a healthy human body. The second mindset is this: of all of the non-toxic micro- and macro-nutrients the human body can process, carbohydrates are the only nutrients unnecessary to human survival. The human body can utilize proteins and fats for energy using a process called ketosis. Finally, and the focus of this article: consuming too many carbohydrates is detrimental to human health, due to volume of carbohydrate intake and because many forms of abundant carbohydrates are anti-nutritional.
It should be noted that the Paleolithic Diet has a large amount of sub-groups, advocating differing guidelines to eating. Thus, this particular article focuses on the three largest food groups that three accepted and leading experts in this particular approach Loren Cordain, John Durant, and Mark Sisson agree on avoiding: grains, legumes, and processed sugars.
List of Grains
- Wheat (refined and whole grain)
- Rice (white, brown, and wild)
- Corn (of all varieties)
- Vegetable oil (many of which include pressed grains)
‘[C]ereal grains and legumes even contain “antinutrients”, chemicals that actually prevent your body from absorbing the proper nutrients and can damage the gastrointestinal and immune systems. Too many grains and legumes can disrupt the acid balance in the kidneys as well, and can contribute to the loss of muscle mass and bone mineral content with aging’ (Cordain).
‘Grains also contain high levels of mild, natural plant toxins known as lectins. Researchers have found that lectins can inhibit healthy gastrointestinal function by damaging delicate brush borders that allow appropriate forms of nutrients (glucose, amino acids, fats, vitamins, and minerals) to travel from the digestive tract into the bloodstream. Lectin damage allows larger, undigested protein molecules to infiltrate the bloodstream. The ever-vigilant immune system sees these unfamiliar protein molecules (not necessarily lectins, but anything you ingest that was supposed to be fully processed in the digestive tract before entering the bloodstream) and sets up a typical immune response to deal with them. Unfortunately, these undigested protein molecules can resemble molecules that reside on the outside of healthy cells, leaving your immune system confused as to who the real enemy is. When your healthy cells come under attack by a confused immune system, you experience what is known as an autoimmune response, something experts believe is the root cause of many diseases’ (Sisson).
List of Legumes
- Beans of all kinds
- Peas of all kinds
- Soybeans and all non-fermented soybean products
- Vegetable oil (many of which contain pressed legumes)
‘Legumes contain many toxins. Lectins are a class of proteins also found in cereal grains. Some lectins bind with nutrients and make them unavailable to the body. Since they prevent nutrients from being absorbed by the body, they are often called antinutrients. Another antinutrient is phytic acid, which binds with zinc and other micronutrients in the gut. (Soaking can help break down phytic acid, and the bacteria used for fermentation help reduce the amount of antinutrients.) Lectins and phytic acid also inflame the gut and can cause diarrhea and bloating’ (Durant).
‘Too much glucose in the bloodstream is toxic, and the body releases the hormone insulin to store excess glucose in muscles, liver, and fat tissue. Unlike with glucose, the body does not use fructose directly, but shunts it from the bloodstream to the liver, where it is converted into glycogen (a stored form of energy). The liver has only a limited capacity to store glycogen, about the equivalent of a couple pieces of fruit, less than one can of soda. The rest must be converted into fat through a slower, less efficient, and more damaging process. Excessive consumption of fructose contributes to the development of fatty liver disease, kidney stones, and gout. Fructose also reacts with proteins in the body to form advanced glycation end products (AGEs), which, appropriately enough, cause a variety of symptoms of aging’ (Durant).
‘The chemical name for table sugar is “sucrose”. It has two additional characteristics that make it particularly harmful for insulin metabolism. First, it is 100 percent carbohydrate, meaning that its glycemic load is very high. Second, when your body digests sucrose, it is broken down into two simple sugars; high-glycemic glucose (with a glycemic index of 97) and low-glycemic fructose (with a glycemic index of 23)’ (Cordain).
- Cordain, Loren. The Paleo Diet. 2nd ed. Hoboken: John Wiley & Sons, 2011.
- Durant, John. The Paleo Manifesto. New York: Harmony Books, 2013.
- Sisson, Mark. The Primal Blueprint. 2009.