Prof Leong: Prevent the preventable, delay the inevitable

By Sharon Siddique

MDS Secretary

About 45 of us gathered on Saturday afternoon to hear a lecture by Dr Leong Seng Kee on “Nutritional Supplements and AMD”. Before his retirement from the National University of Singapore, Dr Leong was Professor and Head of the Department of Anatomy.

One of his special research interests is the human nervous system, including the projection of the eye to the brain. This gives him a unique perspective on macular degeneration – its causes, its treatment, and its prevention.

According to Prof Leong, the causes of macular degeneration are multi-factoral, and can be divided into two categories – non-modifiable and modifiable. Non-modifiable factors include age, family history, genetic makeup. Amongst the most important modifiable factors are quitting smoking, including green leafy vegetables and fish in the diet and avoiding transfat, and controlling hypertension and other chronic conditions.

Reducing modifiable risk factors cannot cure macular degeneration, but there are studies to show that an antioxidant-rich diet, including nutritional supplements, can retard the rate of deterioration.

Taking a combination of antioxidants, including Vitamin C, Vitamin E, Vitamin A (betacarotine), zinc and copper, can stop the progress of macular degeneration at the mild stage in 28% of those on such supplements. Thus in terms of modifiable factors, good nutrition is critical, and nutritional supplements appear to help to prevent, or slow, the process of macular degeneration.

Dr Leong, however, also pointed out that there have been counter-studies, which have actually linked an intake of Vitamin A and E to an increase in mortality. Other studies find no relationship between high antioxidant intake and a slowing of macular degeneration. According to him, these studies are based on meta-analysis. No new research is undertaken, rather many existing studies are “trawled” for results. Such studies must be interpreted carefully because they are very selective in the cases they chose for comparative analysis.

He concluded his talk with several things to remember. First, nutrients work in synergy; they can’t be assessed in isolation; they must be taken in combination. Second, the power of nutrients is in prevention, not in cure. Third, quality control in supplements is very important. For example, always choose natural vitamin E, and not the synthetic vitamin E.

Dr Leong recommends the use of supplements, and he uses them himself. He sees nutritional supplements as having the ability to “prevent the preventable, and delay the inevitable”. An inspiring thought for all of us to take home and ponder.

Talk on Nutritional Supplements

TOPIC: Nutritional Supplements and Age-related Macular Degeneration

SPEAKER: Dr Leong Seng Kee

VENUE: All For Eyes

Tanglin Shopping Centre #05-23

19 Tanglin Road

Singapore 247909

DATE: Saturday, 21 June, 2008
TIME: 2:30pm to 4pm

As we have LIMITED SPACE, please ring Anne (62387387) to confirm your attendance, or send Sharon an email at alleyes@singnet.com.sg

All For Eyes is honoured to have Dr Leong Seng Kee to speak to us on the topic of nutritional supplements and AMD. Those of us with macular degeneration have certainly read many reports on the pros and con of vitamin and herbal supplements. Which ones, what dosages, and how often, are questions which we have all faced after our diagnosis.

We are all concerned with getting a clearer picture of current thinking on nutritional supplements, particularly from a more holistic perspective. We are therefore very grateful that Dr Leong has agreed to share his lifetime of insights with us.

Before his retirement from the National University of Singapore, Dr. Leong was Professor and Head of the Department of Anatomy. His special research interest is the human nervous system, including the projection of the eye to the brain. He has published more than 100 research papers in internationally refereed journals.

For many years Dr Leong has also maintained an interest in the area of nutritional supplements and general health. His friend of 40 years, Victor Wong (senior legal practitioner) said of him: "When Dr. Leong tells you something he means what he says and you will not regret taking him seriously".

Oily fish prevents MD

Australian scientists have found that eating foods rich in omega-3, such as oily fish, can help to prevent vision loss due to macular degeneration.

Oily fish are those fish which have oils throughout the fillet and in the belly cavity around the gut, rather than only in the liver like white fish. It does not refer to fish which are cooked in a lot of oil!

Omega-3 could cut down on the risk of people developing age-related macular degeneration (AMD) by as much as a third.

The researchers said that eating oily fish twice a week could help cut down on the chances of getting AMD as the body gets older.

Fish oil is oil derived from oily fish.

Watch your chicken rice

Eating too many plates of chicken rice and mee goreng may not be good for macular degeneration patients. While delicious, foods like that are "bad" carbohydrates that can significantly increase the risk MD, according to a study in the United States.

Low glycemic or "good" carbohydrates are found in foods containing whole grain, whereas high glycemic or "bad" carbohydrates are found in processed foods such as white rice.

Researchers say evidence is building that "bad" carbs rating high on a glycemic index

can cause spikes in blood sugar that are unhealthy for eyes, whereas "good" carbs help stabilise blood sugar.

Dietary glycemic index is a scale used to determine how quickly carbohydrates are broken down into blood sugar, or glucose. Refined carbs like white bread and rice have high glycemic indices. Whole wheat rice, pasta and bread have low glycemic indices.

The study found that men and women older then 55 who consumed diets with higher-than-average dietary glycemic index foods appeared to have an increased risk for both early and later stages of AMD.

"No one has been able to identify an effective noninvasive intervention that will slow the progress of AMD," said Dr Allen Taylor, a director of the research team.

"We feel we have identified a risk factor that could postpone the debilitating loss of vision with very little economic or personal hardship. Based on our data, limited refined carbohydrates intake, such as by limiting sweetened drinks or exchanging white bread for whole wheat, in at-risk elderly could reduce the number of advanced AMD cases by 8 percent in five years. This can equate to saving the sight of approximately 100,000 people."

10 best foods for eyes

American nutritionist Joy Bauer has come up with a list of top 10 foods for those suffering from AMD. The criteria: foods that are rich in the antioxidants beta carotene, vitamin C, vitamin E, lutein and zeaxanthin, zinc and omega-3 fats.

Here are her top 10 picks:

1. Carrots
2. Bell peppers
3. Broccoli
4. Brussels sprouts
5. Ostrich
6. Turkey
7. Sweet potatoes
8. Spinach
9. Wild salmon
10. Sardines

Click here to read her explanation of the choices and even suggestions on how to cook it!

MDS Sharing Session

Topic: Hi, I have macular degeneration
Date: May 17, 2008 (Sat)
Time: 2pm to 4pm
Venue: Seminar Rm, Alexandra Hospital

How do you tell others that you have macular degeneration? What are some of the problems you face when sharing about your vision problems? Is it better to say it or hide it?

Come join us for an intimate afternoon of sharing over coffee and tea. Hear how others tell their family, friends and colleagues about their struggle with macular degeneration. And share your own experience in communicating about MD.

Register with Anne 6238-7387 or Shing Huei pehshinghuei@gmail.com

Gene therapy breakthrough

For the first time, researchers have used gene therapy to improve the vision in patients who are virtually blind. The breakthrough is offering hope to hundreds of thousands of patients with vision impairment, including macular degeneration sufferers.

Even though the experiments were conducted on those with a rare form of blindness called Leber's congenital amaurosis, researchers believe the approach can ultimately be used for a broad spectrum of disorders, including retinitis pigmentosa and MD.

The experiments were done in both the United States and Britain. In London, three patients were treated, with no ill effects. Even though they did not improve their visual acuity, one of them, 18-year-old Steven Howarth (below), had improved light sensitivity, especially at night.

Before the operation, Howarth was made to walk through a maze. He kept bumping into things and was disoriented. Six months after treatment, he walked through as fast as a normal person!

In Pennsylvania, the results were more impressive. The three patients were treated in one eye each. After two weeks, all reported improvement. One of them could read 3 1/2 lines better on an eye chart.

"All three subjects are asking if they can have their other eye injected," said Dr. Katherine A. High of Children's Hospital of Philadelphia. "That's a pretty good indicator of its effectiveness."

Another researcher hailed the results as a "landmark" and the most important therapeutic discovery in four decades in the field of retinal dystrophies.

Dogs given the same treatment have remained stable for at least eight years.

Gene therapy is when a defective gene is replaced with a good one. In the case of the Leber's, both groups of researchers used a gene called RPE65 that is defective in many Leber's patients.

For MD, it is caused by other defective genes. But the treatment principle would be the same. Researchers would have to design a specific delivery vehicle, or vector, for each disorder bearing the proper gene.