Tuesday, July 31, 2007

Lutein and Zeaxanthin for Healthier Knees

Lutein and zeaxanthin, aside from maintaining our good vision and preventing cardiovascular disease, can also lower the risk of getting arthritis when we get older.

I dread imagining myself having arthritis. I want to be mobile and move around as I want. Limiting my movement because of the pain arthritis may cause is scary.


A 10 year study led by Dr. Yuanyuan Wang of Monash University in Melbourne, highlights the potential of diet to modify the risk of osteoarthritis.

The findings "highlight the potential of diet to modify the risk of osteoarthritis," they report in the online journal Arthritis Research & Therapy. Dr. Yuanyuan Wang of Monash University in Melbourne led the research.

The study was made to 293 men and women who were all:

  • middle aged
  • healthy
  • having healthy and pain free knees

All subjects completed a 121 food frequency intake questionnaire to mainly to assess antioxidant intake.

After 10 years, all the knees of the subjects were examined using MRI(magnetic resonance imaging) for cartilage volume, bone area, cartilage defects and bone marrow lesions.

The results:

  • The subjects who had higher levels of dietary vitamin C had a 50% reduced risk of bone marrow lesions
  • The subjects who had high fruit intake had a 28% reduced risk of bone marrow lesions
  • The subjects who had higher intake of lutein and zeaxanthin had 29% reduced risk of cartilage defects.

The bones that meet in our knee joints have cartilages that serves as a cushion and shock absorber. It also enables the knee bones to slide smoothly from each other. Without these cartilages, the bones would rub against each other causing pain.

Some causes that can damage the cartilage of the knees.

  • Alignment of the knees(bow legged or knock-knee'd)
  • Overweight
  • Physical injury

In the long run, cartilages in the joints can be damaged through wear and tear. Intake of lutein and zeaxanthin as the study above suggests, can minimize the damage when we get older.

Lutein and zeaxanthin belong to the carotenoid family just like the popular beta-carotene. They are fat soluble meaning they can be stored in our bodies.

Lutein can be found in the red, orange, and yellow pigments of fruits and vegetables. Some sources are:

  • Squash
  • Tomatoes
  • Broccoli
  • Green peas
  • Brussel sprouts
  • Carrots
  • Spinach
  • Yellow corn

The egg yolk is also a good source of lutein and zeaxanthin.

If your diet are short of these sources, lutein supplements are also commercially available.

The benefits of lutein in our bodies:

  • It maintains good vision for the eyes.
  • It lowers the risk of macular degeneration.
  • It lowers the risk of cataracts
  • May help in preventing or slowing down of artery thickening which could result in atherosclerosis and eventually to cardiovascular disease.

Our knees may be strong today but how about several years from now? It could be damaged from wear and tear. Maybe we should be taking precautions to prevent or minimize the damage to make us mobile and productive for a longer time.