A Link Between Metabolic Health and Nerve Health

We rely on our nerves to relay sensory information like smell, touch, and taste from our senses, skin, muscles, and organs to our brain. Nerves are also responsible for sending information in the opposite direction, from our brains to our muscles and organs, for physical movement, digestion, and other bodily functions. Imbalanced blood sugar and nerves can be related too.

Is my nerve health at risk?

When the nervous system is dysregulated, a wide array of symptoms follow, from discomfort and numbness to difficulty swallowing.

Diagnoses related to blood sugar dysregulation are still on the rise [1]. One common long-term consequence of dysregulated blood sugar is damage to the nerves.

Healthy nerves require sufficient nutritional intake, and some nutrients are more important than others in terms of nerve support. Certain nutritional insufficiencies can also be the underlying cause of nerve discomfort and tingling [2]. Specifically, B vitamins (B-6, B-12, folate, and thiamine) levels are some of the most important to analyze [3].

B-Vitamin Deficiencies and Nerve Damage

A lack of B-12 depletes the myelin sheath that surrounds nerves, protecting them and aiding in the fast transmission of information. This damage can result in symptoms of tingling, burning, and numbness. B-12 is also a necessary cofactor in the maintenance of normal homocysteine levels. Healthy homocysteine levels are associated with healthier nerves.

B-6 is another cofactor needed for the remethylation of homocysteine to methionine. 

Folate is also supportive of both healthy homocysteine levels and healthy nerves.

Insufficiency of thiamine can create slowed reflexes, pins and needle sensations, and major cognitive issues if left untreated. 

In many cases, it may not even be your diet that’s the problem. Some of these nutrients can be depleted by common medications, including some medications used to balance blood sugar (yes, it’s a vicious cycle) [4]. 

High homocysteine and genetic issues like MTHFR polymorphisms may be additional risk factors for diminished nerve health [5,6]. Awareness of your genetic makeup and how your body gets nerve-supportive nutrition can help you protect the function of delicate nerve tissue.

How does high blood sugar cause nerve pain and damage?

High blood sugar doesn’t cause nerve discomfort directly. It’s the perfect storm of metabolic changes associated with blood sugar dysregulation that negatively affect nerve health over time. 

Factors like obesity, insulin resistance, and imbalanced blood sugar and blood lipids, all stimulate increases in advanced glycation end products, chronic inflammation, oxidative stress, and mitochondrial dysfunction in cells. Metabolic disruption becomes further affected, resulting in changes in underlying factors that are detrimental to nerve and microvascular health. 

Long-standing issues with blood sugar can result in physical discomfort from damage to nervous tissue, often (but not always) starting in the feet. In addition to direct damage to the nerve, changes also result in the slowing of nerve regeneration [7]. The protective coating of the nerve, called myelin, begins to thin, slowing the transmission of impulses along the nerve. Eventually, the nerve density in the skin is also reduced, further decreasing the response of nerves to stimuli [7].

How do I know if I need a nerve support supplement? 

If you experience challenges with blood sugar balance, physical discomfort in the extremities, or are concerned with nutritional deficiency, especially in the B vitamins, you may want to consider adding a nerve support supplement to your health regimen. 

Of course, we always recommend addressing both your health concerns and potential new supplements with your physician before making any changes. If you are already experiencing symptoms related to your nerves, that is the most important point to address with your physician. A supplement is not a treatment or cure for any disease.

How do I know if I’m vitamin deficient?

A blood test ordered by your doctor is the best way to determine your circulating levels of active nutrients. In terms of nerve health, a few important insufficiencies to look out for would be B-12, B-6, folate (B-9), and thiamine.

What causes B-12 deficiency? 

Vitamin B-12 insufficiency is quite common, especially in the elderly and in strict vegetarians. 

B-12 levels change depending on the amount of stomach acid and intrinsic factor (a protein specifically made to help your body absorb B-12) available to assist absorption. These tend to wane naturally as people age and are negatively influenced by common medications that reduce stomach acid. 

Other common medications deplete B-12 [8,9]. This is yet another reason those with blood sugar balance should be extra cautious of caring for the nutritional needs of their nerves. 

Gastric bypass surgery, Crohn’s disease, and ulcerative colitis can also result in difficulty in absorbing B-12. 

Luckily, it can be an easy fix. Studies show that oral forms of B-12 supplements are highly effective for replenishing B-12 levels in the body [10]. 

What causes folate deficiency? 

Folate needs may be increased in those taking medications that are known to deplete folate [11-13].

In addition, useful folate levels are different for a certain percentage of the population with the MTHFR gene polymorphism. The C677T polymorphism is associated with a greater risk of both high homocysteine and nerve damage [5,6]. 

L-methylfolate is the bioactive form of folate that bypasses the MTHFR enzyme and is a more bioavailable form than folic acid. MethylPro® is a high-quality, leading brand of L-methylfolate supplements available in a range of doses to fit individual needs.

What causes vitamin B-6 deficiency?

Multiple drugs are known to deplete B-6 as well [14]. 

With this vitamin, it is important to note that an excess can also create nerve issues [3]. For these reasons, the Tolerable Upper Limit for supplemental vitamin B-6 intake is 100 mg per day for those 19 and above. While it usually takes much more of this vitamin to create nerve issues, guidelines are conservative for supplemental safety.

What causes a thiamine deficiency? 

It is rare, but not impossible to have a thiamine deficiency from dietary lack alone in a developed country. 

Excessive alcohol consumption is typically what depletes thiamine. Alcohol use can create alcohol-induced nerve issues which can be worsened by alcohol’s depleting effect on body stores of thiamine [3].

Can you repair nerve damage nutritionally?

Relative to many other body tissues, nerves are slow to recover from damage for numerous reasons. 

Nervous tissue is slow growing and lacks strong circulatory support. Because damage is often the result of an underlying condition, that condition may continue to create trauma to the nerves if left unresolved. For example, supporting your blood glucose balance is a good first step if you suspect changes to your nerve health may be a result of dysregulation in that area.

Caught early, it may be possible to reverse some blood sugar-associated nerve discomfort from nutritional deficiencies. You may also be able to slow the progression of issues from other causes with behavioral and nutritional changes.

1. Stop smoking & excessive drinking

The reasons-to-avoid-smoking list is long, and here is an addition: smoking constricts the small blood vessels that nourish nerves and can lead to the progression of nerve damage from any cause [15].

As mentioned above, drinking to excess can cause alcoholic nerve damage [3]. It can also deplete thiamine levels which can contribute to nerve issues.

2. Exercise (safely)

Exercise provides several potential benefits to those suffering from nerve-related discomfort.

Because fall rates and balance issues are higher in those with damaged nerves, strength and balance training appear to help. One study examined the effect of a focused exercise regimen on balance, in those with blood-sugar imbalance issues. The patients’ regimen was focused specifically on building strength in the ankles. By the end of a 3-week exercise intervention, the study group showed improvement over the control group in clinical measurements of balance [16]. 

An extensive review of the effect of exercise on diabetic neuropathy notes studies showing beneficial effects on sensation, neuropathic pain, nerve regeneration, and overall longevity of nerve health [17].

3.Take your vitamins

Several of the B vitamins support nerve health. Among these are B-6, B-12, and folate [3,18]. Thiamine and riboflavin also play a role in maintaining nerve health. 

Riboflavin is involved in the healthy metabolism of other B vitamins including folate and B-6 [19]. As such, it has a positive influence over homocysteine levels. High homocysteine is a risk factor for developing nerve issues [20].

Magnesium is a mineral that plays a role in the normal transmission of nerve impulses. High glucose states use more magnesium, leading to a higher risk of deficiency in those with high blood sugar [21]. Magnesium plays a role in modulating normal insulin response. It is common for people on a standard American diet to get less than the recommended amount of magnesium.

Alpha Lipoic Acid is a fat and water-soluble antioxidant. Doses of 600 mg per day have been just as beneficial as some higher doses tested [22]. Studies also show some beneficial effects regarding insulin resistance. Because it may reduce blood glucose levels, it is important to check with your physician before starting Alpha Lipoic Acid if you are on medications that also reduce blood glucose. 

Metabolic Maintenance® makes a nerve support formula called NERVEsustain™ that includes all of the B vitamins above and magnesium, in potencies based on clinical research.

How does NERVEsustain™ support the peripheral nervous system?

Supplements are only a single part of a multi-factor approach, adjacent to balancing blood sugar for nerve health. However, NERVEsustain™ nourishes nerve health with an array of bioactive B vitamins known to be integral in maintaining proper nerve function. 

In addition, this combination of vitamins supports healthy homocysteine levels, as high homocysteine and associated MTHFR polymorphisms may be other risk factors in diminished nerve health. 

As discussed above, certain common medications have been studied to deplete some of these important B vitamins over time. You can protect your nerve health with optimal amounts of supportive nutrients delivered in a single daily capsule.

  • Nourishes healthy nerve function and structure
  • Provides key nutrients for homocysteine metabolism
  • Delivers bioactive forms of B vitamins, including L-methylfolate
  • Supplies optimal amounts of nerve supportive nutrients in a single daily capsule

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  2. https://www.neurologic.theclinics.com/article/S0733-8619(13)00012-1/fulltext
  3. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/
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  17. https://www.frontiersin.org/articles/10.3389/fncel.2014.00102/full
  18. https://journals.sagepub.com/doi/abs/10.1177/0748233713511513
  19. https://search.informit.org/doi/abs/10.3316/informit.633670105175318
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  21. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4549665/
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