Our thoughts, emotions, personality, senses, movements, regulation of vital organ functions and hormones, and the immune system–essentially everything that makes us “us”–depends on a functioning, integrated and healthy nervous system. To experience the best in life, it helps to have optimal brain and nerve health. And yet, because we can’t “see” it, we tend to give little thought to promoting the health of our nervous system until problems arise.
Read on to learn steps you can take to ensure you are “wired for success”, with tips on how to protect and optimize your nervous system! This post explores risk factors for neuro-disease and decline, as well as the research linking diet and inflammation to brain and nerve health.
Brain and nerve health: Don’t appreciate what you got, until it’s gone
Alzheimer’s disease, Parkinson’s disease, cognitive decline, multiple sclerosis, anxiety, depression, neuropathy, neuro-degenerative syndromes, neuro-motor diseases, chronic pain syndromes…these illnesses can adversely impact every aspect of our lives.
Changes that can occur in your brain and nerve health as you age even in absence of a diagnosis of disease include:
- Slowing of thinking ability and memory retrieval
- Reductions in senses (sight, touch, hearing, smelling, tasting)
- Slowing of movements and reaction time
- Increased clumsiness/ decline in coordination
A decline in any of the above functions, functions we use every day of our lives, can adversely affect your work, quality of life, as well as your health and fitness goals.
Neurological conditions such as dementia, multiple sclerosis, etc., can be a nightmare! And despite all our science advances, the origin of these some of these diseases remain subjects of ongoing research.
The precise underlying factors that contribute to neurological decline and disease are still under study. However, research has shed light on factors that can influence our brain and nerve health, and reduce the risk or impact of some of these dreaded diseases.
Risk factors: which ones can we control?
The underlying causes of neuro-degenerative diseases along with nervous-system disorders in general are incredibly complex and varied. Underlying factors implicated in neuro-disease as understood at this time include:
- Oxidative stress
- Prion disease: abnormal proteins that cause chain-reaction damage and destruction of various nerve cells–prions can be obtained from infected meat or contaminated medical equipment or transplants. .
- Toxin stress (such as toxins ingested in food as well as exposures from our environment)
- Inflammation
- Dysfunction in clearing metabolic waste products and proteins from within nerve cells, leading to cell dysfunction and ultimately, cell death
- Trauma such as serious or repetitive head injuries (sometimes encountered in certain sports or due to other causes such as accidents, etc.)
- Alcoholism
- Nutrient deficiencies
- Certain viruses and infections (Lyme disease, Epstein-Barr virus, hepatitis C, shingles, leprosy, HIV)
- Certain medications can damage nerves
- Genetic mutations and susceptibility
- Thyroid disorders
Peripheral nerve diseases (diseases of any of the nerves that extend outside of the brain, such as the nerves of the spinal cord, eyes, face, arms, legs, and those regulating your heart, lungs, and other body functions) have similar risk factors as the nerve diseases affecting the brain.
While the above represent direct effects on our brain and nerve health, indirect processes have been identified as significant risk factors for nerve cell damage and disease. For example, the following conditions DOUBLE your risk for Alzheimer’s dementia:
- Cerebrovascular/ vascular disease
- High cholesterol
- Diabetes
- Smoking
Obesity raises your risk for Alzheimer’s disease by approximately 60%!
Issues such as genetic mutations may not be within our total control. However, many of the above risk factors are impacted strongly by our food choices, exercise habits, and environment! Choices we make now may have powerful influence regarding our nerve and brain health both now and in the years ahead!
Dietary factors influencing brain and nerve health
Cerebrovascular disease, obesity, diabetes, cholesterol…these very significant risk factors for Alzheimer’s are strongly driven by dietary habits. Obesity, cholesterol, and diabetes risk factors are significantly reduced by plant-based diets.
Research has repeatedly linked dietary patterns to either risk of or protection against cognitive impairment, as well as Alzheimer’s disease.
Specifically, Mediterranean diets rich in fruits, vegetables, whole grains, nuts, and legumes–and lower volumes (or elimination) of animal products–have been found to be protective against loss of brain neurons, protection of brain size and volume during aging, and protection against Alzheimer’s disease.
Research has also shown that diabetics that switch to vegan diets are frequently able to eliminate diabetic and pain medication dependence. Up to 80% of those suffering from nerve pain experience COMPLETE relief from nerve pain after just 4-16 days following a vegan diet!!!
What gives?
Diets and chronic inflammation
Dietary factors appear to have a significant impact, not only on the health of our hearts or general health, but on the functioning of our brain and nervous systems. Unhealthy diet choices have been linked chronic inflammation.
Conversely, healthy food choices have anti-inflammatory effects. Inflammation has been strongly implicated in the processes that occur in Alzheimer’s disease. For example, research on the brains of persons with Alzheimer’s disease reveals:
- Chronic activation of immune cells found in the brain–microglial macrophage cells
- These cells release pro-inflammatory cytokines including interleukin-1β, interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α)
- Chronic exposure to these cytokines leads to brain shrinking, nerve cell death, destruction of blood vessels in the brain, and accumulation of nerve cell waste products
Not only that, researchers have noted just mild increases in hemoglobin A1C (a measure of blood sugar trends in the body) and C-reactive protein (a marker of inflammation in the body)–even while still within normal range–are predictive of decline in nerve function in the arms and legs (peripheral nerves).
What was once attributed to “normal aging” of the nervous system–slowed conduction, decreased reactivity– is increasingly recognized as damage due to inflammation and elevations in blood sugar (even below diabetic levels)!
Diet factors that promote inflammation
Diets common to Western cultures have been linked to disruptions in immune system function and and disruptions in metabolism. Nutrients linked to inflammation include:
Saturated fats
Found largely in animal-based foods such as various meats and dairy products, baked-goods, along with palm and coconut oils
Cholesterol
Found exclusively in animal-based foods such as meat—even in lean cuts of meat–as well as eggs, shellfish, and dairy products
Sugar and refined grains
The key here is added sugars (such as soft drinks, snack foods, pastries), and processed foods like pretzels, white breads, processed cereals, etc. Sugars found in whole, plant-based foods are fine.
Why? Because they are paired with fiber, water, absorb more slowly into your body, and are found in relatively low amounts in whole foods.
Purines
These are found in both plant and animal-based foods, though the richest sources tend to be meat, seafood, and organ foods (like liver). In excess, purines can cause uric acid levels to rise above desirable levels, contributing to inflammation, kidney disease, vascular disease, and gouty arthritis.
Despite purines being found in high amounts in certain plant-foods–such as soy–plant-based diets have been found to protect against high levels of uric acid and gout related disease. Meat, alcohol, seafood, and excess fructose on the other hand raise the risk of high uric acid levels and related diseases.
Dietary carnitine
Dietary carnitine is found exclusively in animal-based foods. Red meat, dairy, and eggs are rich sources. When metabolized in the gut, a by-product called trimethylamine N-oxide (TMAO) is produced.
TMAO is strongly linked to cardiovascular disease. Contributing to clot formation and fatty deposits in the arteries (atherosclerosis), TMAO may also play a role in contributing to liver damage (non-alcoholic fatty liver disease) and kidney disease. As TMAO levels rise, all-cause rates of death (mortality) also rise.
Interesting enough, when vegetarians were given carnitine supplements, TMAO levels did NOT rise. However, in omnivores, the rise in blood and urine levels were significant–reaching harmful levels. The difference in response is attributed to differences in gut-microbes that naturally occur between vegetarians and omnivores as a response to diet patterns.
Inflammatory foods in summary:
Except refined sugar and grain, the above inflammatory components are found in animal products: cheese, dairy, meat (including lean cuts), seafood, and eggs. Foods linked to both declines in cognition along with higher levels of circulating inflammatory immune cytokines (proteins)–specifically interleukin-6–include:
- Processed meats
- Red meat
- Fried foods
- Peas and legumes when prepared with sugar and meat (baked-beans)* ( research has linked 3 or more servings of legumes to improved cognitive performance)–how the beans are prepared–such as baked-beans that include added sugar, ham and bacon–increase IL-6 per researchers
- Lack of whole grains in the diet
Diet factors that are anti-inflammatory
Our diets can heal or harm our bodies. Anti-inflammation nutrients are abundant in plant-based foods and include the following:
Fiber
The most anti-inflammatory nutrient in this list, fiber is a major nutrient abundant in plant-based diets. Fiber serves as food for health-promoting strains of bacteria in the gut.
Indeed, research has found that the effects of following a plant-based, vegan diet, leads to healthy Prevotella (health promoting) to Bacteroides (inflammation promoting) ratios (P/B), and promotes growth of the health-promoting species Bifidobacterium and Lactobacillus.
The results of these health promoting gut-microbe changes include:
- boosted insulin sensitivity
- lower cholesterol
- reductions in growth of colon cancer cells
- reduced proliferation of harmful bacteria species
Monounsaturated fats
Abundant in plant-based foods such as nuts, olive oil, and avocados, these fats can reduce LDL (“bad”) cholesterol levels and have a mild anti-inflammatory effect within the body. Indeed, adding nuts and olive oil into a Mediterranean-style diet was shown to reduce stroke and heart attack events by 30%!!
Omega-3 fatty acids
Powerfully anti-inflammatory, omega-3 fatty acids inhibit release of inflammatory cytokines, promote production of anti-inflammatory molecules in the body, and reduce formation of autoimmune antibodies (antibodies that attack our own bodies). These fatty acids include α-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA).
Omega-3 fatty acids are used in the formation of all of our cell membranes.
- Nuts (especially walnuts) for ALA omega-3’s
- Seeds (chia and flax) for ALA omega-3’s
- Oils (flaxseed oil, soybean oil, and canola oil) for ALA omega-3’s
- Algae oil* for DHA and EPA omega-3’s
- Cold-water fish* for DHA and EPA omega-3’s
*DHA and EPA are typically found in only seafood sources, though vegan supplements made from algae (the same source for fish!) can be found readily, such as this product.
Healthy levels of omega-3 fatty acids appear to:
- Reduce risks of Alzheimer’s disease and various forms of dementia
- Promote healthy memory
- May protect against heart disease
- May protect against certain cancers
Research shows that DHA and EPA omega-3 fatty acids can directly lower inflammation in the brain by blocking release of pro-inflammatory cytokines from microglial cells (immune cells in the brain).
Polyphenols / food-based antioxidants
Found abundantly in whole, minimally processed plant-based foods, polyphenols appear to have protective roles against neuro-degenerative and cardiovascular diseases, certain cancers, and obesity. Polyphenols have strong anti-oxidant activities, scavenging harmful-free radical byproducts.
Numerous polyphenols have been shown to reduce inflammation. Polyphenols include anthocyanins, catechins, flavanols, flavones, flavanones, and isoflavones.
Excellent sources of research-backed, inflammation reducing polyphenols include the following:
- Mushrooms
- High-phenol virgin olive oil
- Vegetables, particularly dark leafy greens such as spinach, broccoli, onions, garlic, artichokes–and many others–just eat your vegetables! 😉
- Green tea
- Coffee
- Cocoa
- Sage (a member of the mint family)
- Pe’ur tea
- Turmeric (found in yellow curries)
- Resveratrol (found in high amounts in red wine and itadori tea)
- Fruits (particularly in peels and skins), including especially pomegranate extracts, black currants, blue berries, strawberries, apples, citrus fruits, plums, pears
- Nuts (particularly in hulls)
Indeed, ECGC found in green tea, along with polyphenols in wine and curry have been found to have significant cognitive and nerve cell protective effects! Actions of polyphenols include:
- Blocking toxins by binding to cell receptors, or binding with toxins to neutralize them
- Heavy-metal (iron) chelating effects (binding and neutralizing of harmful metals)
- Antioxidant effects
- Reduction of inflammation with influence on immune cytokines.
- Prevention of abnormal cell growth
- Prevention of new fat cell formation (anti-obesity effects)
- Promotion of increased energy expenditure (anti-obesity effects)
- Protection of insulin-producing beta-cells (anti-diabetic effects)
- Slowing of starch, protein, and fat digestion (anti-diabetic effects)
- Protection against cholesterol oxidation, anti-platelet effects (protects against blood vessel clots–cardio/ cerebrovascular protective)
- Lowering of blood pressure (cardio/ cerebrovascular protective)
Study findings link polyphenols to improved brain and nerve health
Significant reductions in neuro-degenerative disease risk have been demonstrated with as little as one glass of wine per month.
Indian and South Asian nation populations regularly consuming turmeric and curry have been noted to have better cognition and lower risks of dementia verses members of the population who ate little curry.
Mushrooms– 2 or more servings per week were correlated with lower risk of cognitive impairment. These findings were independent of participant age, gender, education, cigarette smoking, alcohol consumption, hypertension, diabetes, heart disease, stroke, physical activities, and social activities! This means the mushrooms themselves appear to have protective effects.
Animal studies have shown polyphenol-rich strawberry, blueberry, and black currant extracts protect against age-related movement declines and memory impairments.
Research in humans likewise demonstrated improved cognitive function in elders given between 400-600 mls of wild blueberry juice daily. In a separate study of 1,640 people aged 65 and older over a period of 10 years, those with the highest polyphenol intake at baseline had the highest scores in memory and cognition.
This trend continued over a 10-year period, with those maintaining the highest intake of polyphenols suffering the least effects of cognitive decline associated with aging. Subjects were controlled for education level, age, and sex.
Numerous human research trials, including double-blinded, placebo-controlled trials, have found consumption of sage to have significant nerve/ brain-enhancing effects, including:
- Enhanced memory over a 4-month period of use among participants
- Improved attention abilities and reductions in psychiatric symptoms
- A dose-related response enhancing word recall
- Improved alertness, sense of calm, and sense of contentment, with reductions in anxiety
Anti-inflammatory foods in summary
The above anti-inflammatory compounds are found almost exclusively in plant-based foods. Omega 3’s, including DHA and EPA can be obtained from plant-foods and supplements, avoiding the pro-inflammatory saturated fat, cholesterol, and purines found in seafood.
- Whole grains (whole wheat, oats, quinoa, millet)–powerfully anti-inflammatory against interleukin-6
- Fruits and vegetables
- Legumes (prepared without sugar and meats)
- Nuts
- Olive oil
- Red Wine
- Green tea, sage, Pe-ur tea, and possibly itadori tea
- Curry spice and turmeric
- Mushrooms
A quick word on B-12 deficiency
A quick word on vitamin b-12 deficiency. Vitamin B12 is critical for brain and nerve health, along with cardiovascular health. In cases of deficiency, permanent nerve cell and nervous system damage can occur, along with anemia and increases in vascular inflammation.
Vegans, vegetarians will become vitamin B12 deficient without adequate supplementation. Absorption of B12 declines with aging as well, regardless of intake of animal foods. Fortunately, B12 supplements are cheap and readily available.
Wrap-up: using to diet to optimize brain and nerve health
Compounds found predominantly in plant-based diets not only protect us from heart disease, diabetes, high cholesterol, and obesity, but also have powerful anti-inflammatory effects. Combined with anti-oxidant properties, anti-inflammatory compounds in plant-based foods such as fiber, monounsaturated fats, omega-3 fatty acids, and polyphenols have research-backed evidence demonstrating protection and healing effects for our brains and nervous systems.
Interesting enough, as noted by research showing baked-beans strongly contributed to elevations of inflammatory proteins, simply mixing health-promoting foods into meat and sugar-rich diets can be counter-productive. Nearly all the pro-inflammatory compounds (except sugar and refined grain) are found in animal products. Whole food plant-dominant diets are a research-backed strategy to help you feel, move, and experience your world with an optimized nervous system! Just be sure to take your B-12 supplement!
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