Fresh liver--a rich source of nucleotides
This article originally appeared in The Paleo Diet Update, v5, #33 – Nucleotides and the Paleo Diet (August 14, 2009), published by www.ThePaleoDiet.com and Loren Cordain, Ph.D. It was written by Mark Connell of nuBound and is reprinted with permission.
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NUCLEOTIDES AND THE PALEO DIET
Nucleotides are small molecules that are the building blocks of DNA and RNA. They are composed of a nitrogen-containing base bonded to a sugar and one or more phosphate groups. Nucleotides occur in all foods of animal or vegetable origin as free nucleotides or nucleic acids. Their concentration depends on cell density, which explains why organ meats are such a rich source.
Traditionally, nutritionists have dismissed any dietary need for nucleotides arguing that the body can produce them itself. This view has begun to change over the last two decades as a mounting body of research has demonstrated that dietary sources of nucleotides play several key roles.
One hint to the larger story is that the preponderance of foods with high concentrations of nucleotides are Paleo foodstuffs, such as game, organ meats (heart, liver, spleen, lungs and sweetbreads) and whole fish. /1-2 Human milk also contains high levels of nucleotides. /3
Research has uncovered multiple roles for dietary nucleotides, including growth and repair of the intestinal lining and liver, /4-5 modulation of the immune system, /6-7 and protein synthesis, /8 among other functions.
While the body is able to synthesize nucleotides from scratch, dietary sources of nucleotides are now considered semi-essential nutrients /9 under stressful conditions (which hamper the body’s synthesis of nucleotides), such as rapid growth, malnutrition or infection. Additionally, certain tissues, such as the gut, which have a low capacity to produce nucleotides on their own, utilize salvage of dietary nucleotides to meet much of their need.
The long recognized superior health of breast-fed babies /10 is now attributed in part to the presence of nucleotides in mother’s milk. /11 Several infant formula makers now add nucleotides to their cow’s milk-based infant formula in an attempt to more closely mimic nature.
The lining of the gut is subject to rapid turnover with complete replacement occurring in less than one week. /4 Nucleotides assist both the continuous proliferation of cells and promote the development of the folds (villi), which allow proper absorption of nutrients. /12 Maintaining the integrity of the gastrointestinal tract is key in avoiding the complications arising from leaky gut.
Immune suppression is well documented in both endurance and strength/power athletes. /13 Recent studies of athletes supplementing their diet with nucleotides have suggested an improvement in immune function and faster recovery. /14-15
The Paleo Diet offers an abundance of nucleotides in comparison to a Neolithic diet, which includes the newer grains, dairy, and sugar never eaten by our Paleolithic ancestors. Basing your meals on the Paleo Diet, mainly lean meat, seafood, fruits, and vegetables, can help with intestinal permeability, immune function, and other functions that dietary nucleotides have been found to enhance.
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