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Just the thought of candida growing wildly inside your body can make you sick. You’ve likely heard through books, blogs, and personal encounters just how many problems this yeast species can cause. You’ve heard about the chronic fatigue, the inflammation, the painful, bloated, smelly digestion it can cause. You’ve heard of people going on antibiotics for this or that problem only to find that they now have a recurring yeast problem. It is so common that there are literally millions of people in this country dealing with problems from yeast. I’m sure none of this is news to you.

In fact, you may be reading this right now wondering if you yourself are suffering from the ill-effects of Candida albicans.  Do any of the following health challenges ring a bell?:

Common Symptoms Associated with Candida Infections

  • Brain fog
  • Fatigue
  • Sugar and carbohydrate cravings
  • Diarrhea
  • Constipation
  • Allergies
  • Food Sensitivities
  • Insomnia
  • Itchy red rashes
  • Yeast infections (vaginal)
  • Oral thrush and especially a white coated tongue
  • Stress intolerance
  • Gut pain, esp. when under stress
  • Bloating
  • Gas
  • Abdominal swelling
  • Autoimmune syndromes
  • Dry flaky skin (scalp, under eyes, behind ears, armpits and feet)


What you probably haven’t heard about is how MTHFR and genetics plays into this issue. What you thought was just an issue with yeast, is in fact a much, much bigger phenomenon. We know that yeast aka Candida (for our purposes we will call them the same thing) is not just a pathogen in our gut, it is also a normal part of our digestive system. Candida is a normal part of the microbiome – the word used to describe the different micro organisms which live in and on our bodies. Without these bugs we couldn’t be alive. A healthy microbiome gives us a healthy sense of well being. On the other hand, if the microbiome gets imbalanced we can become chronically ill or face a life-threatening illness such as sepsis or Candidiasis. And like most processes in our body, this issue of Candida interacts with and influences the methylation cycle. I have termed this phenomenon MTHFR and the Candida Connection.


Overview – What Candida Is, Eats, and Poops

I realize not everyone reading this has a background in biochemistry.  And I also realize it may have been a few years since you took microbiology 101.  Not to worry however I’ll refresh your understanding of what you need to know. We are going to discuss what Candida is, what Candida eats, and what Candida poops:

  • Yeast is the most simple form of eukaryotic cell in existence.  In other words, Candida represents the most simple type of living organism that has a cell wall. Yeast are primitive organisms but, like us, they have a cell wall.
  • Bacteria are different, they have no cell wall and they are classified as prokaryotesViruses do not have a cell wall either.
  • Yeasts produce energy through fermentation, by breaking down sugars without the presence of oxygen.
  • Through the process of fermentation, Candida creates acid byproducts, alcohols, aldehydes and other other chemical toxins that leak into our bodies (and mess with our methylation cycle).

Its very important to realize that Candida lives on sugars.  To prove this point you don’t have to be a doctor.  Just think of how we make wine (or any alcohol for that matter).  We place sugary grape juice into barrels, place yeast inside, shut off all air and light, and let the yeast grow and ferment the grape juice into wine.  Candida depend on sugar to survive and Candida can only produce energy through fermentation – burning sugar in the absence of oxygen. Without sugar the Candida cannot grow.

Reading this you may realize that Candida is not the only thing in our bodies that thrives on sugar, as many are aware the cancer cells also only feed and live on sugar.  There are lots of parallels between cancer cells and Candida but that is too big of a topic for this post.  However this desire for sugar is why eating high carbohydrate diets or taking multiple rounds of antibiotics both set the stage for rapid Candida growth.  Without sugar in our diet Candida would be kept in check.  And without sugar in our diet, inefficient cells that use fermentation instead of aerobic respiration die off (which is how low sugar diets help fight cancer).  When an individual restricts carbohydrate intake and lowers sugar in their diet, cancer cells and Candida will both start to die off because they are being starved of their main fuel source.

The problem is Candida produces aldehydes along with alcohol, and these aldehydes pollute our system and can become neurotoxins.  Interestingly, our bodies also produce aldehydes as part of the neurotransmitter cycle- and aldehydes are toxic. No matter if they come from our bodies or from the action of Candida in our gut, these aldehydes can easily become neurotoxins. This is one big reason why people with yeast issues often have more brain fog, poor cognition, and mood changes than simply gut problems. In other words, Candida interferes with our biochemistry, our methylation cycle, by pooping out aldehydes that interfere with the neurotransmitter cycle.


Is Yeast Always a Bad Thing?

We know that Candida eats sugar and derives ATP from fermentation.  In the process of fermenting sugar, Candida also gives off the vitamin NAD into the environment – into our system.  Our bodies have learned that Candida can provide us with something useful like NAD which becomes critical for survival under conditions of stress.  Since NAD is the main facilitator of around 400 redox reactions (per Linus Pauling Institute) it make sense that our body would tolerate a microorganism like Candida in exchange for something useful in the form of NAD. It has even been suggested in the research that Tuberculosis, Candida and other chronic infections are tolerated by the body because they release the key vitamin niacin into our system.  If a microbe helps our body, then our immune system will ignore it – this is why we are literally covered with microbes from head to toe.

Many species work symbiotically with our bodies, and we wouldn’t be alive without them. In fact studies have shown that in patients with AIDS and Tuberculosis, giving high doses of NAD speeds up the healing of TB. This supports the idea that the infection was really just a way to get a vitamin into the body, and once the vitamin levels were restored, the body didn’t need to “tolerate” the infection any more.

Aside from being a vitamin factory, Candida is also partly invisible to the immune system and it may have developed a relationship with our immune cells that allows it to grow.  Since Candida is a normal part of the gut flora, it suggests that Candida does have a positive role to play during healthy circumstances.  If Yeast truly was all bad, then it would be considered a pathogen, not a comensual or normal part of the microbiom of the gut.


The MTHFR and Candida Connection

Candida connects to MTHFR by way of interfering with the NAD-related catecholamine pathways.  Not only do the chemicals pooped out by yeast shut down MTHFR-related pathways like glutathione and methionine synthase, they also deplete us of NAD.   Essentially we are caught in a vicious cycle where candida slows down our already-slowed-down MTHFR pathway and depletes us of NAD.  As NAD levels drop we lose tryptophan, serotonin and melatonin because the body tries to make more NAD from tryptophan.  I’ve covered this exact subject in another post titled The Tryptophan Steal – The Hidden Reason Stress Makes You Depressed.  If you want more information about how low NAD, caused by candida and other infections, can cause depression then make sure to read that article also!

Ever wonder why getting really stressed out leaves you feeling drunk, foggy and out of touch like you have been drinking?  Excess stress can raise catecholamine by-products that can impair your balance, your thinking, your planning, and your focus just like alcohol.  The reason is that high stress hormones – aka catecholamines – turn into alcohol in our brain.  If these levels are not dealt with (and they require vitamins like B3 and others to properly detoxify) then the neurons themselves become damaged.  This leads to neurotoxicity of the neurons and degeneration of the brain.


Figure 1 – Catecholamine detoxification pathway showing interference from Candida aldehydes and alcohols

In the figure above you can see I have drawn brown circles around the ALR (aldehyde reductase), ALDH (aldehyde dehydrogenase) and ADH (alcohol dehydrogenase) enzymes. These enzymes are necessary to detoxify and get rid of excessive stress chemicals like dopamine, norepinephrine and epinephrine. This chart helps show you in graphic form where and how Candida infections and imbalances will override your MTHFR-related neurotransmitter cycle. When an individual has higher-than-normal levels of yeast, their detox enzymes will be busy trying to deal with the alcohol and aldehydes coming from the gut instead of quickly detoxing stress chemicals in the brain, muscles or liver. This will amplify the effects of stress and lead to unwanted side effects of too many catecholamines – anxiety, insomnia, chronic pain, brain fog, memory issues, depression, etc.

What alcohol and aldehyde have in common is they share the same detoxification enzymes with our own neurotransmitters and they both DEPLETE NAD from our bodies. The reason is that the enzymes required to break down alcohol are THE SAME ONES REQUIRED to break down aldehydes.  Yes, alcohol and aldehydes BOTH use the SAME pathways in our bodies, which also happens to be how we detoxify catecholamines like dopamine, epinephrine and norepinephrine. This is the main reason why MTHFR and methylation pathways connects with Candida pathways – it all happens via the neurotransmitter cycle detox pathways!

One other connection between methylation and Candida is the molecule histamine. Histamine is a neurotransmitter that is very chemically similar to dopamine and adrenalin. And like dopamine and adrenalin, histamine is also detoxified through the aldehyde system as well. On the Figure 1 above you can see yellow arrows inside the brown circles. These arrows represent where histamine detoxification and processing overlaps with dopamine and Candida problems. In other words, any problem with too much dopamine or too much Candida can lead to too much histamine! How many people dealing with Candida issues also have allergies, food intolerances, and histamine symptoms in general?

In Summary

In the methylation cycle the toxic effects of excess catecholamines are felt neurologically and throughout the sympathetic nervous system.  The reason is that catecholamines like DOPAMINE and EPINEPHRINE/NOREPINEPHRINE all turn into ALDEHYDES and ALCOHOLS!!! Candida also produces toxic aldehydes/alcohols and so do we. EVERY single solitary catecholamine that is produced in your brain will in fact be turned into an aldehyde on its way out of our body.  It will also be turned into an alcohol. What if we can’t convert these intermediate molecules into their final end products?  What if our methylation cycle is overmethylating and we are creating WAY TOO MANY catecholamines all the time?  What if we also have a yeast issue, producing even more aldehydes and alcohols? I doubt we will be able to feel healthy and balanced when Candida is interfering with such a basic and powerful detoxification system.

Yeast is a beast and understanding how MTHFR and methylation impact Candida can help you get to the root cause faster. Instead of chasing one area of the body at a time, seeing the connection from genes to gut to brain allows to you to learn to look at the whole body and make connections. This is a core principal at BeyondMTHFR(TM) and in our Red Mountain Clinic. Candida is a big problem in our society at large due to high rates of antibiotics and high sugar diets. Combine that fact with MTHFR-related problems which aren’t being supported and you realize how many people are dealing with this issue!

In Health,

Dr. Rostenberg

By studying the current peer-reviewed research, Dr. Rostenberg has discovered powerful, natural strategies to optimize gut and methylation function to heal the body.  He can help you uncover the genetic or root causes of your health problem and find a natural solution!  If you would like help overcoming a chronic yeast issue to improve your methylation cycle and reduce/eliminate your symptoms, please contact Dr. Rostenberg at Red Mountain Natural Medicine today. Phone 208-322-7755. Email Website

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