The Whitworths of Arizona, bringing science to you in everyday language.

Friday, September 20, 2013

LBD & Nutrition-3: Antioxidants

Antioxidants are the body's scavengers, they combat free radicals—unstable molecules that can injure healthy cells and tissues. Lewy bodies are generated when healthy proteins are “misfolded” or damaged. It is possible that removing free radicals decreases that damage.

However, this possibly positive result does not come without dangers. Many antioxidants are fat-soluble vitamins which cannot be excreted in the urine. Taken in larger doses than the body can use, the excess is stored and can become toxic, causing liver damage or other problems.

Vitamin A: Found in most fruits and vegetables, some nuts, dairy products, and tuna.
  • Belief: Vitamin A prevents free radicals from turning healthy protein cells into Lewy bodies.
  • Fact:  Not yet proven. Vitamin A may be helpful with other disorders but there is still no scientific evidence that this vitamin is helpful in preventing dementia.
  • Concern: This vitamin is fat-soluble and therefore, dangerous in the large amount of supplements often recommended.
Beta carotene: A vitamin A precursor can be found in most fruits and vegetables, some nuts, dairy products and tuna.
  • Belief: As with Vitamin A, beta carotene combats dementia.
  • Fact: Not yet proven. One small study found beta carotene levels lower in people with dementia than in those without dementia. This same study also found that a higher intake of this nutrient by healthy people was associated with a lower risk of later dementia.   More research is needed before this belief can truly be supported.
  • Concern: Beta carotene is fat-soluble, and therefore can be toxic when taken as supplements in larger than recommended doses.
Vitamin D:  Small amounts can be found in fatty fish such as herring and tuna. It is also added to many dairy products and sold as supplements.
  • Belief: Vitamin D is called the Sunshine Vitamin because just a few minutes of sunshine per day will provide adults with all they need.
  • Fact: False. This is true for younger people. However as people age, their skins become less efficient, resulting in vitamin D deficiencies.
  • Belief: As an antioxidant, vitamin D decreases the risk of dementia.
  • Fact: True. Recent research supports this belief.  
  • Belief: Vitamin D helps to make strong bones and keep them strong, important for people that are accident-prone, as is the case for many with Lewy body disorders.
  • Fact: True. This vitamin promotes calcium absorption and works to keep bones strong.  It also helps to prevent osteoporosis, a common disorder with older women, which can also weaken bones and make them easier to break.
  • Concern: Since this vitamin is less easy to find in foods, doctors may recommend a vitamin D supplement. Be careful not to take more of this fat-soluble vitamin than the recommended dose.
Vitamin E: This antioxidant is found in wheat germ, nuts such as almonds and hazelnuts, vegetable oils such as sunflower and safflower oils, and some green vegetables, such as spinach and broccoli.
  • Belief: Vitamin E decreases the risk of developing dementia.
  • Fact: Partially true. Since we reported on this vitamin in our 2010 book, this vitamin has been found to be helpful for long term prevention and may have a modest impact on the risk of developing dementia later in life.  
  • Concern: The above pertains to vitamin E found in food only. The amount of this fat-soluble vitamin needed be effective in supplement form is toxic and can cause liver damage.
Coenzyme Q10 (CoQ10). This antioxidant can be found in organ meat (heart, liver), vegetable oils, fatty fish, and nuts. Broccoli, sweet potatoes and sweet peppers also contain moderate amounts of this nutrient.
  • Belief: CoQ10 can slow down dementia.
  • Fact: True, but impractical and possibly dangerous. There is some evidence that suggests this coenzyme may slow down but not cure Parkinson’s dementia.
  • Concern: The amount per day required for effective treatment is too large to get easily from food. Supplements are generally used but they are expensive.
  • Concern: A variety of diseases and drugs can interact negatively with CoQ10. For example, it decreases the effect of blood thinners. Also, it is fat-soluble. Be sure to talk to your doctor before adding this nutrient to your diet.
Next week: Water-soluble vitamins.

Vitamin A: Dietary antioxidants and dementia 
Vitamin D: Vitamin D, cognition, and dementia.
Vitamin E:  Dietary Antioxidants and Long-term Risk of Dementia.
CoQ10: CoQ10 and Dementia.

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