Eye diseases and vision loss are becoming more common in the United States as diabetes rates rise and the population ages. Many eye conditions worsen very slowly and have no noticeable symptoms in their early stages. For this reason, getting an annual eye exam is extremely important. But is there anything we can do to prevent eye disease from a nutritional perspective? Experts believe that there is such a thing as an “eye-healthy diet.” I interviewed Dr. Jeffrey Anshel, President of the Ocular Nutrition Society, and Dr. Elizabeth Johnson, a leading nutrition researcher, to get their views on the subject. Please listen to the full HealthyVision podcast here.
Some of the my favorite learning points from the show:
1. Which foods are healthy for the eyes? The human retina contains about 1000 times more concentrated carotenoids (found primarily in plant pigments) than any other part of the body. Our eyes use these pigments to protect themselves from the photo-damage of sunlight. Carotenoids (including beta-carotene, lycopene, lutein, and zeoxanthin) are found in highest concentrations in dark green, leafy and brightly colored vegetables. Egg yolks are also a good source of carotenoids. Interestingly, our retinas have a predilection for omega-3 fatty acids (found in fatty fish) to protect the eyes from UV radiation. My bottom line – the most eye-healthy meal on earth is probably a salmon salad Niçoise (see photo image above)!
2. Are carrots good for our eyes? While carrots can be part of healthy diet, choosing carrots as our primary source of vegetable intake may not be a good idea. Carrots contain beta-carotene, which competes with other carotenoids for transport molecules. Beta-carotene is a pretty good competitor and can “bump off” lutein and zeaxanthin from getting transported to the retina. Adults don’t process beta-carotene as well as kids do, so too many carrots may not be a great thing after all (especially as we get older)!
3. Should I take nutritional supplements for the eye? It’s always best to get your carotenoids from real food. However, some people (who take blood thinners for example) cannot eat dark green leafy vegetables because they also contain Vitamin K which can interfere with the medicines. For those who cannot get sufficient carotenoids from food, supplements may be beneficial.
4. What is the connection between obesity and chronic eye disease? While obesity is a risk factor for diabetes, and diabetes can cause chronic eye disease, there may be another problem at play. Carotenoids are fat soluble, and so they are preferentially stored in fat cells rather than remaining suspended in our blood stream. When we have larger fat stores, that fat may “mop up” the healthy vegetable carotenoids that we eat, without allowing them to be transported to the eyes to support retinal structures. Some researchers suggest that obese individuals may need to increase their carotenoid intake with supplements in order to prevent eye pigment deficiencies and potential macular degeneration. Losing body fat is also an important strategy of course.
Other questions answered in the podcast:
* How does cooking impact the nutritional value of fruits and veggies?
* Is there such a thing as over-supplementation (especially with Zinc)?
* How many veggies do I need to meet my daily carotenoid requirements?
* How do I know which vitamin supplements to trust?
I hope you enjoy the podcast – and redouble your efforts to eat a diet rich in fruits, veggies, fish and eggs and maintain a healthy weight. Remember that even though your mom may have told you that Bugs Bunny’s diet was best for your eye health, Popeye’s veggie of choice is even better for you!
You probably see your primary care physician once a year, and your dentist twice a year. But how often do you see your eye doctor? Vision is the most valued of the 5 senses, and yet Americans don’t seem to be making regular eye exams a priority. A recent CDC survey suggests that as many as 34.6% of adults over the age of 40 (with moderate to severe visual impairment) believe that they don’t need regular eye exams. About 39.8% of the respondents said that they didn’t get regular exams because they were too costly, or because their health insurance didn’t cover the expense.
Although cost may play a role in peoples’ thinking, a comprehensive eye exam costs as little as $45-50 at retail outlets. I suspect that the real reason why people don’t get regular eye exams is because they incorrectly believe that if their vision is stable, their eyes are healthy.
A comprehensive eye exam is a type of medical check up – it is not just a vision assessment. Eye care professionals can diagnose everything from glaucoma and cataracts to high cholesterol, diabetes, high blood pressure, and even neurologic conditions such as brain tumors and multiple sclerosis. The eyes are more than a “window to the soul” but a window to general physical health. And the good news is that exams are relatively inexpensive and painless – so please consider making them part of your yearly health maintenance routine.
And to my primary care friends – don’t forget to encourage your patients to get annual eye exams. As the CDC notes:
Recommendations from primary-care providers can influence patients to receive eye-care services; persons who had visual screening during routine physical examinations had better eye health because of reminders to visit eye specialists. Public health interventions aimed at heightening awareness among both adults aged ≥65 years and health-care providers might increase utilization rates among persons with age-related eye diseases or chronic diseases that affect vision such as diabetes.
I myself have had an unexpected diagnosis during an eye exam, and feel passionate about the importance of preventive screening. In fact, I’ll be the upcoming host of a new eye health education initiative – a radio show called, “Healthy Vision with Dr. Val Jones” supported by ACUVUE brand contact lenses. The first show will be released here today, and it’s also available at Blog Talk Radio.
Last week, Nintendo became the latest consumer electronics maker to warn that kids shouldn’t use their three-dimensional image-based gaming devices because they may have a negative impact on development of the human visual system.
The warning came just a month before the company’s much anticipated release of the 3DS, which is just such a device that features a 3.5-inch screen which can create 3-D images without the need for special glasses. The 3DS is Nintendo’s most anticipated new product since it released the iconic Wii gaming device in 2006.
Sony’s PlayStation3, a similar product that requires glasses to create the 3-D effect, already carries a similar warning, as do 3-D TV sets made by Sony, Samsung, and Panasonic.
Nintendo’s warning applies to kids that are six years old or younger. The Japanese company advised parents to block access to the game machine’s 3-D mode for these kids, while adding that it was okay for them to use the 3DS in 2-D mode. Read more »
*This blog post was originally published at Pizaazz*
Intraocular pressure is usually measured by applying a force on the cornea using a tonometer. Although sufficiently accurate, tonometers are only used in ophthalmologist offices and so don’t measure intra-day pressures. They also fail with people post cataract surgery that have a thicker cornea. Researchers at University of Arizona have developed a new device that measures intraocular pressure through the eyelid.
From the University of Arizona College of Engineering:
The self-test instrument has been designed in Eniko Enikov’s lab at the UA College of Engineering. Gone are the eye drops and need for a sterilized sensor. In their place is an easy-to-use probe that gently rubs the eyelid and can be used at home.
“You simply close your eye and rub the eyelid like you might casually rub your eye,” said Enikov, a professor of aerospace and mechanical engineering. “The instrument detects the stiffness and, therefore, infers the intraocular pressure.” Enikov also heads the Advanced Micro and Nanosystems Laboratory.
While the probe is simple to use, the technology behind it is complex, involving a system of micro-force sensors, specially designed microchips, and math-based procedures programmed into its memory.
We now have another condition that may be prevented by eating a healthy diet, exercising, and abstaining from smoking: Age-related macular degeneration (AMD).
Macular degeneration causes a loss of central vision and makes it difficult to recognize faces and read small print. The macula degenerates with age and severe macular degeneration causes blindness. Treatment is costly and doesn’t work very well.
A new study published in the Archives of Ophthalmology looked at 1,313 women aged 55 to 74 years. They reviewed their diet and exercise habits. Eating a “healthy diet” meant 3.5 servings of fruit and vegetables, 2.3 servings of dairy, 2.7 ounces of meet and 3.5 servings of grain a day. Exercise habits and smoking history were also monitored. Read more »
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