DHA and Micronutrients May Prevent Brain Shrinkage with Age
Vitamins, DHA, and the aging brain
It is known that a Western diet is associated with dementia — the risk factors for Alzheimer’s disease are almost identical to those for cardiovascular disease.1 In contrast, higher vegetable and fruit intake is associated with decreased risk of cognitive decline and dementia.2,3
Vitamins are essential for thousands of chemical reactions in the body, and certain vitamins and other phytochemicals have been singled out for their critically important functions in the brain. These include B vitamins, vitamins C, D, and E, and omega-3 DHA.
• Vitamin B1 is needed in order for the brain to utilize glucose for energys
• Folate is crucial during early brain development and is important for memory s
• Vitamin B12 is important for memory and production of neurotransmitters, and deficiency in B12 can cause nerve injury leading to impaired sensation and even blindness.4 Higher B12 blood levels are associated with slowed cognitive decline.5
• Vitamin B6 is also involved in neurotransmitter production, and deficiency is associated with seizures, chronic pain, and depression.6
Antioxidant Vitamins C and E
• The brain is highly susceptible to oxidative stress, which is one of the main mechanisms of brain aging and a contributing factor to neurodegenerative conditions.7,8
• Nerve endings have highest concentrations of vitamin C found in the human body. Vitamin C is thought to function largely as an antioxidant in the brain and nervous system. Blood levels of vitamin C have been positively associated with IQ.4
• Vitamin E is a component of brain cell membranes, and along with vitamin A and carotenoids, protects vulnerable unsaturated fatty acids (like omega-3s) from oxidative damage. Low vitamin E status is associated with greater risk of Alzheimer's disease.4
• Vitamin C and E intake were associated with higher cognitive scores in the elderly, and the association was stronger for food sources compared to supplement sources.9
• In addition to vitamin intake, polyphenols and other antioxidants present in plant foods are thought to contribute to protecting the brain from oxidative damage.4
• Vitamin D is involved in regulating glucose and calcium transport to and within the brain, and may also protect cognition by reducing inflammation and increasing availability of certain neurotransmitters.4
• Vitamin D is also involved in memory formation.10 Several studies have associated vitamin D deficiency with increased risk of cognitive impairment or dementia in older adults.11,12
Effects of vitamins and DHA on brain shrinkage in the elderly
Compared to older individuals with normal cognition, those with dementia have significantly smaller brain volumes as measured by MRI.17 A recent study analyzed blood fats and micronutrients with regard to MRI measures of brain volume and cognitive function tests in older adults. The researchers found three patterns of nutrient status that correlated to brain volume and cognitive function:
1. Higher levels of vitamins B, C, D, and E — associated with greater cognitive function scores and brain volume. This pattern primarily reflected fruit and vegetable intake.
2. Higher levels of omega-3 fatty acids (DHA) — associated with greater cognitive function scores and brain volume. This pattern primarily reflected fish intake.
3. High levels of trans fats — associated with lower cognitive function scores and brain volume.18,19
Protect your brain
The American diet is insufficient in providing these brain-healthy nutrients, but a nutritarian diet provides both the amount and variety of vitamins and other phytochemicals that support optimal brain function. It is especially important to eat healthfully, supplement with vitamin D, and get adequate DHA as we age, especially after age 50. Keep in mind that fish is not an ideal source of DHA, since mercury is toxic to the brain and reduces the body's antioxidant status.20-23 An algae-based DHA supplement is a healthful, environmentally friendly source of beneficial omega-3 fatty acids. Eating plenty of unrefined plant foods and taking a non-fish source of DHA starting early in life will allow us to maintain valuable vitamins, omega-3s, and other phytochemicals in brain tissue to keep our minds sharp as we age.
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