A Link Between Metabolic Health and Nerve Health

We rely on our nerves to relay sensory information like smell, touch, pain, 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 nerve pain can be related.

Is my nerve health at risk?

When the nervous system is dysregulated, a wide array of symptoms follow, from pain and numbness to difficulty swallowing. “Neuropathy” is the medical term for dysfunction or damage of nerves. Peripheral neuropathy is damage to nerves in the extremities (hands, arms, feet, and legs) often associated with pain, tingling, and/or numbness. 

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

Healthy nerves require sufficient nutritional intake, and some nutrients are more important than others in terms of nerve support. Certain nutritional deficiencies can also be the underlying cause of nerve pain 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. High homocysteine levels are associated with a greater risk of neuropathy.

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

A deficiency of folate is also known to cause neuropathy symptoms associated with high homocysteine levels.

Deficiency 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 pain 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, high blood sugar, and dyslipidemia 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 nerve pain 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, nerve pain, 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 of nerve damage, 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 deficiencies to look out for would be B-12, B-6, folate (B-9), and thiamine.

What causes B-12 deficiency? 

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

B-12 levels are influenced by 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 that deplete B-12 include Metformin [8,9], a common medication prescribed in prediabetes and diabetes cases. 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. These include anticonvulsants [11], Metformin [12], and oral contraceptives [13]. 

In addition, useful folate levels are affected in 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 diabetic neuropathy [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?

Drugs such as antibiotics, oral contraceptives, and the class of antidepressants known as monoamine oxidase inhibitors can all deplete B-6 [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 set at 100 mg per day for those 19 and above. While it usually takes much more of this vitamin to create neuropathy issues, guidelines are set conservatively 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. 

Thiamine is depleted by excessive alcohol consumption. Alcohol use can create alcohol-induced neuropathy which can be worsened by alcohol’s depleting effect on body stores of thiamine [3].

Can you repair nerve damage naturally?

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 pain from nutritional deficiencies or slow the progression of symptoms 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 neuropathy from any cause [15].

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

2. Exercise (safely)

With drug options not always being effective, researchers are also examining other potential ways to positively affect nerve health. Exercise provides several potential benefits to sufferers of neuropathy.

Because fall rates and balance issues are higher in those with peripheral neuropathy, strength and balance training appear to help. One study examined the effect of a focused exercise regimen on balance, in those suffering from diabetic peripheral neuropathy. 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 are known to support nerve health and can create neuropathic issues if deficient. 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 neuropathy [20].

Magnesium is a mineral involved 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 is involved 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. It has been used in Europe for many years to support nerve health. 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 pain. 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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