Q: What is PreserVision?
PreserVision (which was originally called “Ocuvite”) is a pill made by Bausch and Lomb. It contains four dietary supplements: beta carotene, vitamins E and C, and zinc. These supplements are all in megadoses, up to 15 times greater than the recommended daily intake. Bausch and Lomb instructs people to take these pills twice a day, so patients who take it are taking up to 30 times the recommended daily dose of these four supplements.
Q. Who takes PreserVision, and why?
PreserVision is being taken by millions of elderly people, worldwide, who think that it will keep them from losing their sight to Age-related Macular Degeneration (AMD).
Q: What is macular degeneration?
AMD is a hereditary eye disease that destroys the area in the center of the retina, the macula. The macula allows you to see details. It is the number one cause of legal blindness in people over 65 in the US. One out of every three people over 65 will eventually develop macular degeneration.
Q: What is the evidence that these 4 dietary supplements might help patients who have macular degeneration?
The “evidence” comes from study called the AREDS (Age Related Eye Disease Study), which studied the effect of these four supplements. It was published in 2001 in a scientific journal, Archives of Ophthalmology.
The paper does not explain why the researchers chose these 4 supplements. They seem to have chosen them arbitrarily. There was no scientific rational for this study. Nobody understands why they chose them. It has been shown that diets rich in fruits and vegetables protect people against AMD, but we have no idea which of the thousands of different compounds in fruits and vegetables causes this beneficial effect.
Q: Were there any financial conflicts of interest in this study?
The Principal Investigator and Study Chairman of the AREDS Study, Dr. Frederick Ferris, has the patent to this drug. The AREDS study was financed partly by Storz, which is now part of Bausch and Lomb, the company that manufactures these pills.
Q: What was the design of this study?
Three different groups of patients were studied. One group had mild AMD, one had moderate (intermediate) AMD, and one had intermediate AMD in one eye and advanced AMD in the other. Some patients were given the drug, and some were given a placebo. After several years, the patients who got the drug were studied to see if the drug was effective in preventing: 1) the progression of their AMD; 2) vision loss.
Q. What were the results of this study?
The results of the study were negative. The drug had no beneficial effect on vision, and it did not stop the progression of AMD, in any of these three groups of patients.
Q: So why does anybody think these drugs work?
A. After the study was completed, the researchers went back and changed their research design. They arbitrarily threw out all patients with mild AMD from the study. This is a strange decision. Patients with mild disease are the ones who should benefit the most from this drug. Then, they changed their definition of “success”, from: “preventing vision loss and progression”, to: “preventing AMD events”.
After these manipulations, the data seemed to show that the drug prevented what they called “AMD events”, but it did so for only in one group of patients, the one who had intermediate AMD in one eye, and advanced AMD in the other. The study did NOT show that these patients had any vision benefit from taking this drug.
Q. So this study showed that only a small subgroup of AMD patients should take this drug?
The only people who supposedly “benefitted” from this drug are people who have intermediate AMD in one eye, and advanced AMD in the other. No other type of patients had any benefit. Even if a doctor accepts the results of this study, he should only recommend this drug to this small subgroup of patients.
Q. Is it standard scientific practice to change criteria after a study is over?
No. This manipulation has caused a storm of criticism in scientific meetings, and in the scientific literature. Scientists are not supposed to throw out a negative result, and then report on a small subgroup that seems to have a positive result. It does not conform to standard scientific practice. In short, the value of PreserVision has not been proven by accepted scientific methods.
Q. Is Preserveation dangerous to the patients who take it?
A. Yes. PreserVision is very dangerous to people who take it. The vitamins in PreserVision are at doses way above the recommended amount. Vitamins are drugs. All drugs must be taken at their proper dosages. We all know that 2 aspirin will help your headache, but that 20 aspirin can kill you. It is the same with vitamins.
All of the four supplements in this study cause serious problems:
- beta carotene has been shown to cause lung cancer in smokers;
- vitamin E causes lung and prostate cancer, and increases the risk of heart failure;
- vitamin C causes kidney stones, heartburn, and diarrhea;
- zinc doubles the risk of urinary tract problems, including enlarged prostate in men, and incontinence in women.
Q. If Preservation is worthless and dangerous, what can a patient with early macular degeneration do to help their eyes?
- DON’T SMOKE.
- Eat healthy food, which means lots of fruits and vegetables. Michael Pollan correctly says, “Get your vitamins from plants, not from things made in plants”.
- Get yearly eye exams with a retina specialist.
- Stay away from PreserVision, and all other megadose vitamin supplements.
