Vision: Protecting your vision could also help your heart

Here's a series of events that would bring even the most optimistic of us down:

A poor diet is combined with a lack of exercise... which takes its toll in the form of type 2 diabetes... which prompts health problems such as micro vascular disease... which damages tiny blood vessels in the eye... which obstructs blood flow to the retina... which causes gradual vision loss.

But bad as all that is, that's not the end of it.

A new study shows that the cascading health situation described above might be a tip off that the heart is also in danger.

The eyes have it

Scientists have theorised that micro vascular disease could be a risk factor for congestive heart failure (CHF). To test this theory, researchers at the University of Melbourne in Australia examined the relationship of CHF and retinopathy; a disorder (common to diabetes) that blocks blood flow to the eyes and kidneys, and is a marker for micro vascular disease.

The Melbourne team drew on the health records of more than 11,000 middle-aged subjects who participated in a US trial called the Atherosclerosis Risk in Communities Study. All of these subjects had retinal photographs taken to detect symptoms of retinopathy. Researchers used follow up medical records over a period of seven years to determine rates of CHF.

Results showed that subjects with retinopathy had a heart failure rate of more than 15 percent, while those without retinopathy had a CHF rate of less than five percent. This difference was even more pronounced among subjects who had retinopathy symptoms, but at the outset of the study showed no symptoms of heart disease, diabetes or high blood pressure.

Writing in the Journal of the American Medical Association, the researchers conclude that retinopathy 'is an independent predictor of CHF' even if a patient has none of the accepted risk factors of the disease.

In short: Any patient who is diagnosed with retinopathy should be monitored for the development of congestive heart failure.

To the rescue

There are no early warning signs for diabetic retinopathy - when the first symptoms are detected (such as blurred vision), the condition is usually well underway. So in a sense, anyone who is diagnosed with diabetes should consider the diagnosis itself to be an early warning sign.

Fortunately there are steps you can take to minimise your risk of retinopathy, whether or not you have type 2 diabetes.

In a previous e-alert, I told you about a multiyear study of more than 1,300 subjects that examined the effects of dietary and supplemental sources of vitamins C and E on diabetic retinopathy. Researchers found no association between intake of vitamin C or E from food sources and a reduced risk of retinopathy. But those who reported taking supplements of vitamins C or E for three years or more were shown to be significantly less likely to develop retinopathy compared to subjects who didn't use supplements.

Researchers couldn't explain why food sources of the vitamins weren't as effective as supplements. Nevertheless, this study confirms previous animal trials that have shown positive associations between vitamin C and E intake and retinopathy prevention.

Beyond supplementing with vitamins C and E, dietary measures can be taken to help prevent retinopathy. Studies have shown that a deficiency of vitamin B-6 contributes to the condition. B-6 is found in a wide variety of foods including beef, poultry, fish, beans, bananas, spinach, avocados, walnuts and sunflower seeds.

The most effective prevention of retinopathy is the control of glucose and insulin levels. Beyond that, a yearly, dilated eye examination is essential. Pregnancy can also raise retinopathy risk, so some doctors recommend several eye examinations throughout pregnancy for diabetic women.

. . and another thing

It might be too early to say we've spotted a trend, but something unusual is going on, and you've got to like the way it's headed.

Yesterday, I told you about a study that found a clear association between iron deficiency and attention deficit hyperactivity disorder (ADHD) in adolescents.

Now I've come across yet another study that focuses on dietary causes of ADHD.

As reported in the Journal of the American College of Nutrition, a team of French researchers examined the effects of magnesium and vitamin B6 supplements on more than 50 subjects under the age of 15 who had been diagnosed with ADHD. Supplement dosage varied according to body weight, but on average, each child received 100 mg of magnesium and 13 mg of B6 per day for three to 24 weeks.

The researchers found a significant reduction in ADHD symptoms in ALL of the subjects, including improvements in physical aggressiveness and hyper excitability.

And while it's remarkable that I've come across two trials in a week that studied ADHD without the use of drugs, the results are not surprising, thanks to HSI Panellist Dr Allan Spreen, who has made it clear that (in his own words) 'ADHD is fixable without drugs of any kind in the VAST majority of cases.'

But one of the observations Dr. Spreen made about the iron deficiency study also applies to this second study: If a child is deficient in one nutrient, that's a good indication that his overall nutrition picture needs improving. So in addition to adding supplements and making sure the diet consists of a good balance of fresh, whole foods, Dr. Spreen offers this ADHD rule of thumb: 'If food allergies are not dealt with, if sugar and refined white flour are not massively lowered, if artificial additives are not eliminated (colours, flavours, MSG, preservatives, etc.), the changes from supplements could still fail to work properly.'

Meanwhile, here's hoping that these studies are just the first in a long line of trials that will help make parents aware that there's an alternative to the quick fix of ADHD drugs.