Eyesight and Alzheimer's - Be smart. Stay smart and don’t be blue

When was the last time you had an eye test? If you’re like me then it’s been a long time. The importance of having your eyes tested has just been upgraded due to further work in the field of Alzheimer’s research.

This research is showing a link between reduced macular pigmentation in the retina and Alzheimer’s disease.

I think this particularly worrying as damage to macular pigmentation can be caused by humanities newest obsession, staring at things that emit blue light, namely, LCD screens on our mobile devices, TVs and tablets.

Macular pigmentation

Macular pigmentation protects your eyes from absorbing damaging blue light. This pigment is composed of two carotenoids ( a pigment that gives a yellow/orange colour) called zeaxanthin and lutein.

What is blue light?


Sunlight is made up of violet, blue, indigo, green, yellow, orange and red light. When combined together they form white light. Our eyes are naturally exposed to more light from the blue end of the spectrum as it represents a larger portion of white light.

The benefits of blue light

Blue light helps to regulate our bodies natural wake/sleep cycle or circadian rhythm. Believe it or not but for most of our evolutionary history we didn’t watch Netflix until 2 in the morning but went to bed by fire light and woke up with sunrise.

Adequate exposure to blue light also helps elevate mood, keeps us alert and helps with the development of eyesight during development.

The negative effects of blue light

Overexposure to blue light has the potential to put us a risk from macular degeneration which is a leading cause of blindness. Further to this, as already mentioned, Alzheimer’s patients have significantly less macular pigment and lower serum concentrations of lutein and zeaxanthin.

Our heavy dependence on technology, particularly hand-held devices, doesn’t show signs of slowing down anytime soon. While it might be a little early to say definitively that blue light emitted from such devices causes macular degeneration increasing the risk of developing Alzheimer’s the evidence is increasing.

I don’t know about you but I would rather take action now than wait for a generation to go by before we have solid proof.

Reducing the negative effects of blue light

Limit mobile/tablet use

This is especially true in the evening when it gets dark. Try to wind down the use of electronics in plenty of time before you hit the hay.

Use a blue light filter

Most new mobile devices have a setting in the shortcut menu to turn on a “eye saving” or “night mode.” The newer phones will filter out around 50% of blue light from your screen.

If you have an older device just search for your app store for an app that will do the same job, there are plenty to choose from.

Get your eyes tested

Remember, you specifically want a test that checks your macular pigment optical density (MPOD)