BRAIN FUNCTION AND NUTRITION

Brain function and Nutrition

Good nutritional status is important for proper brain development and maintenance of normal cognitive function. Through unique biological functions, various micro nutrients affect brain function. I will discuss the roles of key micro nutrients including the B vitamins antioxidant vitamins, and certain essential minerals, in cognitive function. The cognitive effects of micro nutrient deficiencies are discussed, and the effects of micro nutrient supplementation on the broad areas of attention, memory, executive functions, mood, as well as age-related cognitive decline are covered.

Consequences of Select Micro nutrient Deficiencies

Thiamine

Vitamin B₁)deficiency, like deficiencies in several of the B vitamins, has negative cognitive effects. Adequate intake of thiamine is important for reactions in the brain that metabolize carbohydrates, lipids and amino acids.

Severe thiamine deficiency:

·        Beriberi - Inflammation of multiple nerves (polyneuritis), heart disease (cardiopathy), and edema (swelling) due to a deficiency of thiamine (vitamin B1) in the diet. Symptoms:

• Decreased muscle function, particularly in the lower legs.
• Tingling or loss of feeling in the feet and hands.
• Pain.
• Mental confusion.
• Difficulty speaking.
• Vomiting.
• Involuntary eye movement.
• Paralysis.

·        Wernicke’s encephalopathy - is the presence of neurological symptoms caused by biochemical lesions of the central nervous system after exhaustion of B-vitamin reserves, in particular thiamine (vitamin B1). Symptoms:

• Confusion and loss of mental activity that can progress to coma and death.
• Loss of muscle coordination (ataxia) that can cause leg tremor.
• Vision changes such as abnormal eye movements (back and forth movements called nystagmus), double vision, eyelid drooping.

·        Korsakoff’s psychosis - is a late complication of persistent Wernicke encephalopathy and results in memory deficits, confusion, and behavioral changes. Korsakoff psychosis occurs in 80% of untreated patients with Wernicke encephalopathy; severe alcoholism is a common underlying condition. Symptoms:

• Confusion and loss of mental activity that can progress to coma and death.
• Loss of muscle coordination (ataxia) that can cause leg tremor.
• Vision changes such as abnormal eye movements (back and forth movements called nystagmus), double vision, eyelid drooping.
• Alcohol withdrawal.

Niacin

The Vitamin B₃ Co enzymes NAD and NADP, are needed for several redox and other reactions in the body.

Niacin deficiency,

·        Pellagra

o   Headache

o   Fatigue

o   Apathy

o   Depression

o   Ataxia

o   Poor concentration

o   Delusions

o   Hallucinations which can lead to confusion, memory loss, psychosis and eventual death.

Vitamin B₆

A form of vitamin B₆ is required coenzyme for the biosynthesis of several neurotransmitters , including GABA, dopamine, norepinephrine, and serotonin . The vitamin has a number of other biological functions. Vitamin B₆ concentrations in the brain are about 100 times higher than levels in the blood; thus vitamin B₆ deficiency has neurologic effects.

Severe deficiency of vitamin

·        Seizures

·        Irritability

·        Depression

·        Confusion

Vitamin B₁₂

Vitamin B₁₂ deficiency, which affects 10-15% of adults over the age of 60, is frequently associated with neurological problems. Compared to younger individuals, this vitamin deficiency is more common in older adults because of the higher prevalence of food-bound vitamin B₁₂ malabsorption (atrophic gastritis) and the higher incidence of the autoimmune condition.

Vitamin B₁₂ deficiency;

·        Numbness and tingling of the extremities, especially the legs;

·        Difficulty walking

·        concentration problems

·        Memory loss

·        Disorientation

·        Dementia that may or may not be accompanied by mood changes 

While the biochemical mechanisms underlying the neurological effects of vitamin B₁₂ deficiency are not understood, the vitamin deficiency is known to damage the myelin sheath covering cranial, spinal, and peripheral nerves 

Vitamin C

Vitamin C accumulates in the central nervous system, with neurons of the brain having especially high levels. In addition to its well-known antioxidant functions, vitamin C has a number of non-antioxidant functions.

Calcium

Calcium ions are important intracellular signals that regulate a number of physiological processes.

Calcium inadequacy can cause Muscle aches, cramps, and spasms are the earliest signs of a calcium deficiency. People tend to feel pain in the thighs and arms, particularly the underarms, when walking and otherwise moving. A calcium deficiency can also cause numbness and tingling in the hands, arms, feet, legs, and around the mouth.

Iodine

Iodine is required for the synthesis of thyroid hormones that regulate a number of physiological processes, including growth, development, metabolism, and reproduction.  In addition, thyroid hormones are important for myelination of the central nervous system, which mostly occurs before and shortly after birth. Because iodine is critical for normal development of the brain, deficiency of this mineral during critical periods, such as during fetal development or during early childhood, can have deleterious effects on cognition.

Iodine deficiency

·         Swelling in the Neck. S

·         Unexpected Weight Gain.

·         Fatigue and Weakness.

·         Hair loss.

·         Dry, Flaky Skin.

·         Feeling Colder Than Usual.

·         Changes in Heart Rate.

·         Trouble Learning and Remembering.

Iron

Iron is an essential component of hundreds of proteins and enzymes involved in various aspects of cellular metabolism, including those involved in oxygen transport and storage, electron transport and energy generation, and DNA synthesis. Iron is needed for proper development of oligodendrocytes (the brain cells that produce myelin), and the mineral is also a required cofactor for several enzymes that synthesize neurotransmitters.

Iron deficiency during various stages of brain development has detrimental consequences. Pregnant women are at increased risk of iron deficiency because iron requirements are significantly increased during pregnancy due to increased iron utilization by the developing fetus and placenta and because of blood volume expansion Maternal iron deficiency has serious consequences for the woman and the fetus. Iron deficiency during prenatal stages results in persistent deficits in learning and memory. Moreover, iron deficiency in later stages of development; such as during childhood, may be associated with impaired cognitive development, while iron is essential for brain function, it is toxic to neurons at high concentrations 

Selenium

Selenium is necessary for the conversion of the thyroid hormone thyroxine (T4) into its more active counterpart triiodothyronine (T3), and as such a deficiency can cause symptoms of hypothyroidism, including extreme fatigue, mental slowing, goiter, cretinism, and recurrent miscarriage.

Symptoms of selenium deficiency

·         Infertility in men and women.

·         Muscle weakness.

·         Fatigue.

·         Mental fog.

·         Hair loss.

·         Weakened immune system.

Zinc

Zinc is found in cells throughout the body. It is needed for the body's defensive (immune) system to properly work. It plays a role in cell division, cell growth, wound healing, and the breakdown of carbohydrates. Zinc is also needed for the senses of smell and taste.

Zinc deficiency

·         Altered/loss of taste and smell.

·         Anorexia (lack or loss of appetite)

·         Apathy.

·         Ataxic gait (uncoordinated movements)

·         Decreased immunity.

·         Depression.

·         Diarrhea.

·         Excessive hair loss.