Dr. Bruce Holub- Latest Research On Omega-3
- Tuesday, 03 May 2011
Dr. Bruce Holub is the Director of Scientific Affairs and Information for the DHA/EPA Omega-3 Institute and a University Professor Emeritus at the University of Guelph’s Department of Human Health & Nutritional Sciences. Naturally Savvy’s Lisa Tsakos interviewed Dr. Holub about the latest information and research on omega-3 fats.
Naturally Savvy Question (Lisa): What is the latest information about omega fats that we should be aware of?
Dr. Holub: One area which has been researched lately is the aging population. Long-term population studies show that with EPA/DHA intake over an extended period of time there is a pronounced reduction in age related maculopathy of the eyes (which can lead to a loss of vision).
Also, there was a large study done in the United States showing that women who are taking regular supplementation of EPA/DHA had a significant reduction of about 32 percent in the risk of developing breast cancer. This is consistent with other studies showing that women who consume more fish have a lower breast cancer risk.
Naturally Savvy Question (Lisa): Nutritional supplement trends come and go based on research. Omega-3 fats have been studied for years. Is there any question about whether or not they are safe?
Dr. Holub: In my opinion, omega-3 fish oil is a pretty safe supplement. For some supplements, consumers are advised to wait a while longer for studies to confirm their safety. But omega-3, especially in terms of the recommendations for heart disease, is considered to be safe at doses of up to 3,000 mg of combined EPA/DHA.
A number of long-term studies have been done on cardiovascular disease. Those who consume five to seven servings of fish a month have a 35 to 40 percent lowered risk of having a cardiovascular event. This has been well established. Many Asian studies have confirmed the benefits of omega-3 on heart disease. In Japan, the recommendation is to eat fish seven times a week or to take a supplement daily.
Naturally Savvy Question (Lisa): What are your thoughts on molecular distillation? Is there a better way to purify fish oil?
Dr. Holub: Molecular distillation is the most commonly used way to make fish oil concentrates. More expensive technologies may come down in the future, for example, super-critical extraction technology. A small number of manufacturers are already using this technology. It’s another option but it is more expensive and there is no proof that it’s a better process. Almost all of the studies showing the benefits of omega-3 fish oils have been done using concentrates purified by molecular distillation.
Naturally Savvy Question (Lisa): What is the current recommended ratio of omega-3 to omega-6 fatty acids?
Dr. Holub: The Harvard Nurses’ Health Study, conducted on 88,000 nurses, shows that women who consumed more omega-6 had lower rates of cardiovascular disease; yet people today continue to talk about the dangers of omega-6. Most of the studies showing the health benefits of omega-3 have been done on studies which also included a high intake of omega-6.
This line of argument is a red herring (no pun intended). The main issue is not the ratio of omega-6 to omega-3. The main issue is the insufficient intake of long chain omega-3 fatty acids - regardless of the omega-6 to omega-3 ratio.
The typical diet has 12,000 to 14,000 mg of omega-6 in North America. Ninety percent of the fats we consume daily fats are omega-6. An insufficient intake of EPA/DHA from marine sources is responsible for 87,000 American deaths per year. There have been no recorded or known deaths from omega-6 sources. A higher omega-6 to omega-3 ratio in the body is a risk factor for inflammatory processes and chronic disorders, but that’s very different from the ratio in the diet.
Naturally Savvy Question (Lisa): Some of the original studies done on omega-3 showed an improvement in the symptoms of depression. Is omega-3 still recommended as a treatment for depression?
Dr. Holub: Studies published in the Israel Journal of Psychiatry showed that ten-year old kids who were given 300 mg of DHA/EPA showed a 40 percent reduction in depression (rating scores) compared with those receiving placebo within eight to ten weeks. Surprisingly, EPA may be moderately more effective than DHA for depression, but the reasons are not well known. The brain is mostly composed of DHA and has very little EPA, but it’s possible that the dilatory effects of EPA may affect the brain, even though it doesn’t accumulate in the brain.
For pregnancy, lactation and visual support, DHA is the more important of the two.
Mixtures of DHA/EPA have been used in most of the studies, so always recommend a combination of the two until we know better. Always go back to the published literature.
For depression, either a one-to-one ratio or a two-to-one ratio of EPA-to-DHA is recommended.
When buying fish oil supplements, however, look at the amounts of EPA/DHA on a supplement label, not at the ratio of EPA to DHA. The ratio may be effective for marketing purposes, but it doesn’t always make sense for consumers (and is often abused in the marketing of a product). The public may not be getting the right advice when they’re getting advice about ratios; they need advice about the amounts. In other words, don’t focus on the ratios.
Naturally Savvy Question (Lisa): Which is the best type of fish oil for ADD and ADHD and what dosage should we give to children with ADD/ADHD? What about children who don’t have ADD/ADHD?
Dr. Holub: A recent review of all the studies was done, and most of the studies show no beneficial effect of omega-3 on ADD/ADHD. The major review article concluded that there is no consistent benefit of EPA/DHA supplementation. Having said that, there are isolated (small) studies; in other words, to use hockey terms, “a whole string of ties and no losses.” There is insufficient evidence based on the numerous studies that have been done.
Naturally Savvy Question (Lisa): Is krill oil a more effective form of omega-3 than oils from other fish?
Dr. Holub: Krill oil has been receiving a lot of attention lately, but it’s rather low in EPA/DHA compared with most other supplements on the market. It typically has 240 mg per capsule (of combined EPA/DHA), so 24 percent of the weight of the oil is EPA/DHA. A standard dose of EPA/DHA is 180 mg EPA and 120 mg of DHA, equalling 300 mg. Also, krill oil doesn’t have as much omega-3. Science has not confirmed a greater bioavailability from krill oil than from other sources.
Naturally Savvy Question (Lisa): Recent studies have challenged whether or not saturated fats are as dangerous as was once thought. What’s your opinion?
Dr. Holub: Realize that much of the concern about saturated fats has historically been on one risk factor, cholesterol. Heart disease is the result of 286 risk factors, many of which have to go astray before a cardiovascular event happens, so you can’t base cardiovascular disease on one risk factor. You can’t run a health care system based on one risk factor.
Saturated fats are a very small player (although not totally innocent). You can have saturated fats in your diet as long as there is a complementary intake and balance of polyunsaturated fats and monounsaturated fats.
We don’t have omega-3 supplementation recommendations in the United States and Canada. Omega-3 concentrates are a wonderful alternative for triglyceride lowering. It can dramatically reduce health care costs. Unfortunately, doctors are not taught this in medical school. With two to three grams of EPA/DHA, one can expect a drop in triglycerides of 25-30 points within three to four weeks.
Naturally Savvy Question (Lisa): Interesterification is sometimes used as an alternative to partially-hydrogenated fats. Is it a safe process?
Dr. Holub: Interesterification appears safe. There have been no published studies indicating that it isn’t.
Naturally Savvy Question (Lisa): How do you think that the disaster in Japan will impact the omega-3 fish oil industry?
Dr. Holub: The tragedy in Japan will affect the public’s perception of quality, and if nothing else, will affect the marketing of products imported from Japan. For those who are concerned, anchovy oil from fish caught off the coast of Peru is very clean. Sardine oil often times comes from Japan (it isn’t always identified).
Savvy Tip: You can (and should) request a certificate of analysis from fish oil manufacturers to confirm the safety and efficacy of the oil you are purchasing. Any responsible fish oil manufacturer should have these available upon request. (Tip courtesy of Nordic Naturals)