What I call the “Methylation Cycle” is actually the intersection of four traffic circles. Traffic circles can be difficult to navigate. If you don’t already know where you are supposed to be exiting you can find yourself in the absolute wrong lane and need to traverse the circle more than once to actually get off at the desired location. The Methylation Cycle is more complex in that all four traffic circles are connected to each other and each one produces critical components that are needed by your body. The combination of two of these circles is well known; the addition of the other two circles is part of what influences the supplement choices for this program. Combining all four of these circles into the Methylation Cycle has allowed me to think about these pathways in a unique manner and define supplementation in a different way. Part of the success of this program is recognizing that what you do in one traffic circle can influence the others.

I will not get too technical in this book. There are a large number of resources I have generated (books, workbook, DVD, PPTs, articles) that go into detail once you are ready to learn more. Getting your arms around this program is like driving a car. My goal in this book is simply for you to understand that this is a car you really need to learn how to drive, in order to have a better Roadmap to health for you and your entire family. In describing these traffic circles I will give you the bare minimum scientific information you need to understand how critical it is for your body to be able to navigate the Methylation Cycle.

  • The first traffic circle involves one of the many building blocks for proteins, an amino acid called methionine. This first circle is aptly named the methionine cycle. This cycle helps to convert homocysteine back to methionine. Buildup of homocysteine has been linked to stroke, heart disease and Alzheimer’s disease among other health conditions. The ability to convert homocysteine to methionine is clearly important for health. If you consider that heart disease, Alzheimer’s, and stroke are all leading causes of death, it is obvious that this is a traffic circle you don’t want to ignore. Not only do you want to decrease homocysteine levels, generating methionine is something your system needs. Lack of methionine has been linked to fatty liver disease and depression and has been used to help offset toxicity due to certain chemical poisoning, for asthma and allergies as well as playing a role in decreasing gray hair.


  • The second circle that is well known to be tied to the methionine cycle is the folate cycle. Folate is simply a B vitamin. So, just as methionine is a building block of proteins that you eat every day, folate is a B vitamin that is found in green leafy vegetables. The folate cycle is linked to the methionine cycle so that they can be envisioned as two gears. The gears are linked and help to drive each other around the circle. The functioning of the folate/methionine cycles drives the regeneration of methionine from homocysteine through the use and conversion of B vitamins.When there are certain mutations in the Methylation Cycle the folate portion cannot function optimally. Since these two cycles are matched together like gears that drive each other’s movement, you can see how Methylation Cycle SNPs can have a direct negative impact on the balance of homocysteine and methionine. In addition, imbalances in this folate/methionine cycle have been linked to everything from neural tube defects, miscarriages, cleft palate, anemia to cancer.

The central point where the first two cycles meet is a step that requires vitamin B12. The need to support B12 is a critical aspect of this program. I will talk more about B12 and the special types of B12 you can consider as well as the importance of lithium with respect to B12 levels. However for the moment, all I ask is that you keep the need for B12 in mind and how it sits at the juncture of the first two cycles.

  • The third traffic circle that is part of the Methylation Cycle is the BH4 cycle. BH4 stands for tetrahydrobiopterin. I do not expect you to even try to pronounce that. But I do want you to understand why BH4 is so important. BH4 is what your body uses to help make the ‘feel good’ compounds in your body, serotonin and dopamine. Most antidepressants on the market today rely on the need for serotonin and dopamine but do not consider the role of BH4. Your body converts tryptophan (from turkey) to serotonin with the help of BH4. Serotonin makes you feel content and satisfied, like a purring cat. Lack of serotonin has been tied to depression. BH4 also helps you make dopamine from another amino acid, tyrosine. Dopamine is the compound that gives you that sense of satisfaction from achievement that gives you motivation and prevents you from being a couch potato. Lack of dopamine is associated with Parkinson’s disease and other movement disorders and imbalances in dopamine have been linked to ADD/ADHD. Together with serotonin, having healthy dopamine levels is a key to feeling happy, content, satisfied, focused and motivated.

Certain mutations in the Methylation Cycle may impair the ability to generate healthy BH4 levels. This fact ties together the BH4 traffic circle to the first two traffic circles we already spoke about (methionine and folate). BH4 levels are further compromised by environmental toxins including aluminum, lead and mercury. So, underlying SNPs in the Methylation Cycle combined with toxic chemicals can further diminish much needed BH4 levels. In addition, bacterial infections in the body can throw off the balance of BH4. So adding in infectious agents along with toxins and SNPs helps to create the ingredients for that perfect storm of BH4 deficiency. Low levels of BH4 can then cause a range of problems including feeling depressed, unmotivated, a lack of focus and movement issues.

  • The final traffic circle that is a part of the Methylation Cycle is the urea cycle. This is the cycle that helps the body get rid of ammonia, which is toxic, and convert it to urea which can be excreted. Lack of BH4 not only impacts dopamine and serotonin as discussed above, but also plays a role in the urea cycle. BH4 helps to generate products that cause less oxidative damage. In the absence of sufficient BH4 more oxygen related damaging compounds are produced from the urea cycle that can cause neurological inflammation.

By this point you should be able to see that the Methylation Cycle is a central pathway in the body that is particularly amenable to nutrigenomic screening for genetic weaknesses. The result of decreased activity in this pathway causes a shortage of critical functional groups in the body called methyl groups that serve a variety of important functions. In general, single mutations or biomarkers are generally perceived as indicators for specific health issues. However, it is possible that for a number of health conditions, it may be necessary to look at the entire Methylation Cycle as a biomarker for underlying genetic susceptibility for nonideal health. It may require expanding the view of a biomarker beyond the restriction of a mutation in a single gene to a mutation somewhere in an entire pathway of interconnected function.

Four Components of the Methylation Cycle

Next Chapter:

Your Body’s Mechanic

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