Dr. Barry Sears Says, "Take Lots of Fish Oil!": The Full Interview -- June 26, 2002
Dr. Barry Sears says, “Eat Your Fish Oil…Lots of It”
An interview with Dr. Barry Sears
By Phillip Whitten
Dr. Barry Sears, creator of the popular “Zone Diet,” discusses his new book, “The Omega RX Zone in an interview with SWIM Magazine editor, Phillip Whitten. An excerpt from that interview appears in the July/August issue of SWIM (pages 30-32). Here is the complete, unedited interview.
The views expressed by Dr. Barry Sears in the interview are, not surprisingly, his own views and do not necessarily represent the opinions of SWIM Magazine or United States Masters Swimming (USMS). Individuals embracing any or all of Dr. Sears’ dietary recommendations are urged by Dr. Sears, SWIM and USMS to consult a medical practitioner or nutritionist and to be followed medically.
SWIM: Your new book is called The Omega Rx Zone. What is the significance of the title?
Sears: The Omega Rx Zone is a dietary prescription using high-dose fish oil rich in long-chain, omega-3 fatty acids in combination with the Zone Diet to achieve a higher level of hormonal control.
The premise of the book is that one of the problems of modern medicine is that we sometimes make it too complex. In particular, virtually every chronic disease can be characterized by two major factors: (1) an increase in inflammation or (2) a decrease in blood flow. My book outlines how the appropriate diet can modify both actions.
Currently, we’re at the crossroads of 21st century medicine: Do we continue to treat the symptoms of chronic disease or will we actively promote wellness? Obviously, promoting wellness is more desirable, but you first have to define what “wellness” is. If inflammation and decreased blood flow are primary factors of chronic disease, then a good working definition of wellness would be: any intervention that decreases inflammation and increases blood flow.
Both inflammation and blood flow are controlled by hormones – in particular, a group of hormones called eicosanoids. Therefore I believe the future of medicine will be based on finding new interventions to change levels of eicosanoids to achieve a reduction of inflammation and an increase in blood flow.
That’s the foundation of The Omega Rx Zone. It’s a life-long program of hormonal control using the food you eat. To maximize eicosanoids control, you need to control insulin simultaneously. The more you control insulin using the Zone diet, the less fish oil you need to control eicosanoids. On the other hand, the less you control insulin, the more fish oil you need to control eicosanoids. This is because it is the long-chain omega-3 fatty acids that are only found in fish oil that allow for maximum eicosanoids control.
SWIM: Early in the book, you assert that fish-eating is essentially what made us human. This idea is not new in the field of anthropology – it’s been floating around for at least a decade – but it may be startling to lay readers. Explain what you mean.
Sears: We know now from genetics that every human being alive today came from a small group of Africans who lived 150,000 years ago. We also know that our ancestors were transformed into modern humans in virtually an instant in terms of evolutionary time. What fundamental changes allowed our puny ancestors, who were dying out as a species, to transform themselves into the Masters of the world?
One compelling hypothesis is that they stumbled upon brain food. The candidate for that brain food was long-chain, omega-3 fatty acids that can only be made by algae.
The starting point for our species appears to come from the East African Rift Valley. Since fishing is a fairly complex endeavor, our early ancestors could only access omega-3 fatty acids by eating shellfish they found along the shores of Rift valley lakes. The meat of the shellfish would have contained far higher concentrations of long-chain, omega-3 fatty acids than other sources of protein that could be found on the African savannah.
In essence, our dominance in the world today may have come from a lucky break when our immediate ancestors began consume higher levels these long-chain, omega-3 fatty acids.
We know now from animal studies that if you take these long-chain, omega-3 fatty acids out of the diet, within two generations the offspring become significantly dumber and their nerve cells shrink in size. Other studies have indicated that increasing the intake of the same long-chain, omega-3 fatty acids increases the intelligence of animals.
The increase in brainpower coming from the dietary intake of long-chain, omega-3 fatty acid would have led to an improvement in the ability of our ancestors to utilize the technology they already had. It took them about 50,000 years to increase in numbers and “consolidate their forces.” Then they left Africa about 100,000 years ago and began to spread around the world.
However, the real explosion in modern man’s dominance took place about 40,000 years ago with the invention of new tool technology, art, and religion. There’s a strong correlation of this intellectual explosion 40,000 years ago with the development of fishing, which would have increased further the dietary intake of long-chain, omega-3 fatty acids. If the intake of these fatty acids made us human, then it will probably be the reason that will be the key to our future both medically and intellectually.
SWIM: There are many studies that have documented the effects of fish oil on a whole host of ailments – heart arrhythmias, heart attacks, heart disease, and reversal of wasting in cancer. None of this is at all controversial. What is unique about your book – and likely to become controversial – is the amount of fish oil you recommend. You recommend a teaspoon a day for normal, healthy people and up to three tablespoons daily for people with such conditions as Alzheimer’s, Parkinson's, MS, schizophrenia, ADD, dyslexia and so on. Can you explain why?
Sears: You’re quite right. The Omega Rx Zone promises to be controversial because of the fish oil dosages I recommend to alter eicosanoid levels. However, I also stipulate in the book how to use certain common blood tests to determine how much fish oil you actually need to take. That takes fish oil supplementation out of the “trust me” category, and now it makes it based upon hard clinical data. This is the basis of what I call evidence-based wellness.
SWIM: What is “evidence-based wellness”?
Sears: Evidence-based wellness is based upon using certain blood tests to tell if you are well or not. Subjective feelings of wellness are not a very good indicator of your future. They don’t tell you what actually is going on inside your body or your brain. The blood tests I recommend are ones that come from prospective clinical studies. These are studies that take individuals with no evidence of any clinical disease, and follow them for several years to determine which blood parameters were most predictive in the development of chronic diseases.
Two of the most predictive blood tests – especially of heart disease are (1) the levels of insulin, which are controlled by the ratio of protein to carbohydrates that we eat and the number of calories we consume; and (2) the ratio of two fatty acids in the blood stream, which give you an estimate of the balance of eicosanoids in your body.
As I stated earlier, improved eicosanoids control will be the key to a longer and better life.
SWIM: Why eicosanoids?
Sears: Because they control the brain, heart and the immune system. They also control inflammation and blood flow. They can be controlled by diet, especially the intake of high-dose fish oil in combination with improved insulin control.
SWIM: Many studies were done on people actually eating cold water fish. If someone does not have any particular health problems, wouldn’t it be far less expensive and still provide significant benefit they simply included more cold water fish in their diets, rather than consume fish oil supplements?
Sears: The clinical data are clear: eating extra cold water fish is protective. However, the amount of cold water fatty fish that Americans are likely to consume is somewhat limited.
There are two populations that consume large amounts of fish: the Japanese, who have the longest, and the longest healthy lifespan; and the Eskimos. Epidemiological studies of Eskimos nearly 30 years ago pointed out some interesting things: they have very low rates of heart disease, MS, depression, diabetes and cancer even though they were consuming a high-fat diet. However, it was one rich in long-chain, omega-3 fatty acids. The amount of intake of these fatty acids and their impact on health could be determined by the ratio of two fatty acids in the blood: arachidonic acid (AA) to eicosapentaenoic acid (EPA). The ratio of these two fatty acids reflects the balance of eicosanoids in the body.
I chose the average of AA/EPA in the Japanese population as an ideal to shoot for.
Their ratio of these two fatty acids is about 1.5. (The average level in Eskimos is about 0.7.) In my studies, I tried to maintain a target range of AA/EPA between 1.5 and 3.0.
By comparison, the average American has a ratio of nearly 11. For people with severe inflammatory pain or neurological disorders, the ratio can range from 20 to 50. The higher the ratio, the greater the disturbances in eicosanoids levels.
If Americans were willing to eat the same amount of fish the Japanese do – which is a lot less than the Eskimos -- there would be no need to supplement the diet with any purified fish oil. Unfortunately, Americans have not demonstrated any such willingness. However, we have a good indication of what a standard dose of fish oil should be if you have no existing chronic condition: the amount of long-chain, omega-3 fatty acids as you’ll find in a tablespoon of cod liver oil, or about 2.5 grams of long-chain, omega-3 fatty acids. The current intake of Americans is five percent of that, about 125 mg per day.
SWIM: Aside from the amount of fish oil you recommend, you make a big point in the book of specifying pharmaceutical-grade fish oil. Why? What’s the difference? In fact, some authorities state that unprocessed fish oil is excellent, but by the time we process it and put it into a pill or bottle it in liquid form, we’ve inactivated most of it.
Sears: Unprocessed fish oil can be considered the sewer of the sea. Everything we’ve thrown into our environment in the last two generations—organic mercury, PCBs, DDT—are concentrated in crude fish oil.
This is why Americans get mixed messages; Eat more fish, it’s healthy. But don’t eat more fish, because they contain toxins.
The only way to solve this dilemma is to purify the fish oil to remove the toxins as well as many of the fatty acids in fish oil, which are incompatible with our digestive tract.
Pharmaceutical-grade fish oil represents the highest quality of fish oil that is available, and in my book I give the standards that it should meet. These are purity standard for the fish oils that have been used in the vast majority of published studies. A pharmaceutical-grade fish oil is not only much more concentrated in long-chain, omega-3 fatty acids, but it also means the amount of impurities normally found in fish oil have been reduced to infinitesimal amounts. This is only possible by making fish oil concentrates in which the fish oil is broken down into its constituent fatty acids and then these are refined to generate a product that can be used in high dosages, leaving behind the vast majority of toxins present in lower quality fish oil such as those you can buy in a health food store. This is no different than using pharmaceutical-grade penicillin as opposed to eating the mold from which penicillin is derived.
SWIM: Isn’t pharmaceutical grade fish oil very expensive and aren’t you also in the business of selling it?
Sears: Yes, it’s more expensive to buy because it’s more expensive to produce. That’s because it takes nearly 100 gallons of health-food-grade fish oil to make one gallon of pharmaceutical-grade fish oil.
And yes, it’s also true that my company does market pharmaceutical-grade fish oil, as does the company owned by Harvard Medical School professor Andrew Stoll, who did all the pioneering studies of high-dose fish oil in the treatment of bipolar depression, and as does the drug company in Norway that sells pharmaceutical-grade fish oil as a prescription drug in Europe for lowering triglycerides.
SWIM: What about side effects of fish oil? Haven’t some studies identified possible side effects including excessive bleeding, increased risk of stroke and increased LDL cholesterol levels? Are you concerned that taking greater amounts of fish oil will increase the risk of these side effects?
Sears: I address all of the potential side effects of increased fish oil consumption in my book. I also then go through all of the existing literature to see if there’s scientific support for the purported side effects.
As example, let’s take increased bleeding. The data are quite clear. The intake of long-chain, omega-3 fatty acids at the level of 16 grams/day will have about the same effect on bleeding as one aspirin per day.
SWIM: And what about LDL levels?
Sears: Most studies indicate little, if any, increase. However, there is a drastic shift in the size of the LDL particles with increased fish oil intake. There are two types of LDL particles, that is, “bad cholesterol”. There’s the good, bad cholesterol, and the bad, bad cholesterol.
The good, bad cholesterol consists of big fluffy LDL particles that float around like beach balls in the bloodstream. They appear to have very little potential to cause heart disease. On the other hand, the bad, bad cholesterol are the small, dense LDL particles which are highly implicated in the development of heart disease.
What high-dosage fish oil does is convert much of the bad bad cholesterol into the good bad cholesterol, thereby reducing the likelihood of heart disease. This helps explain why the Japanese and Eskimos have such low rates of heart disease, in addition to the proven benefits of increased blood flow and decreased inflammation..
As for stroke, a recent study in Lancet addressed this particular question in Eskimos. Only when the ratio of AA to EPA was less than 0.5 was there an increase in the risk of stroke. On average, Eskimos are about 0.7. This is precisely why we use this ratio to determine the amount of fish oil one should take, and recommend a lower limit of 1.5, which is found in the Japanese population.
To reach an AA?EPA ratio of 1.5, the average American would have to be taking three tablespoons of cod liver oil, or one tablespoon of pharmaceutical-grade fish oil, simply to match the levels among the Japanese, who are the healthiest people on Earth.
That is why I state clearly in my book that anyone taking more than two tablespoons of pharmaceutical-grade fish oil should always check the ratio of AA to EPA in order to maintain it within the range of 1.5 to 3, because that is the primary marker of wellness.
SWIM: It sounds almost too good to be true, and I’m always wary of things that sound too good. In fact, one of your detractors has said it almost sounds more like snake oil than fish oil. If what you say is true, what is the underlying commonality among all these diseases and conditions that make them treatable through eating fish oil?
Sears: Look, any intervention, whether it be a drug or a diet, if it does too many things, it’s accused on being the equivalent of snake oil. Because eicosanoids control the brain, heart, immune system, any drug or dietary intervention that changes their levels might be construed as snake oil because it does so many things. In the 20th century we had a drug that fell into that category. That drug was aspirin.
Aspirin is an amazing drug for the number of things it can do. It prevents heart attacks, cancer, decreases pain and reduces inflammation. How could one drug do all these things? It’s because aspirin changes the levels of eicosanoids. Although it doesn’t lower cholesterol, it remains the primary drug anyone with a heart condition takes to prevent a heart attack.
If aspirin was the Wonder Drug of the 20th century by changing levels of eicosanoids, I set out 20 years ago to discover the dietary methods to alter eicosanoids so it might become the Wonder Drug of the 21st century.
SWIM: You keep talking about eicosanoids, but many people—even many physicians—have never even heard of eicosanoids.
Sears: That’s right… even though the 1982 Nobel Prize in Medicine was awarded for understanding the role eicosanoids play in chronic disease, and even though there have been 87,000 published articles on eicosanoids since 1966. For anyone to say eicosanoids are not important, means they are ignorant of the existing medical literature.
If you’re going to say that high-dose fish oil is equivalent to snake oil, then we should be prepared to label aspirin as snake oil as well, since it, too, affects eicosanoids..
SWIM: You write that “bad” eicosanoids increase inflammation and decrease recovery rates after workout. Have you done any double blind studies on randomly chosen athletes comparing recovery times? Without studies, isn’t this just conjecture?
Sears: The statement that “bad” – that is, proinflammatory, eicosanoids increase inflammation is well understood in the medical community. That’s why the various drugs we have in medicine—like aspirin and NSAIDs such as Motrin, and corticosteroids like prednisone—have only one mode of action: they decrease inflammation caused by overproduction of pro-inflammatory eicosanoids.
At the same time, it is well-known that there are a great number of anti-inflammatory eicosanoids, especially recently-discovered ones by Harvard Medical School. The most powerful of these are derived from the long-chain, omega-3 fatty acids found in fish oils. If the goal of an athlete is to reduce inflammation caused by training, thereby enhancing recovery, it’s quite clear that by manipulating the balance of eicosanoids we can do exactly that.
Although there are no defined studies on athletes – even though they are great consumers of anti-inflammatory drugs – we do have many double-blind, placebo-controlled studies that high-dose fish oil reduces inflammation in patients with chronic inflammatory diseases such as arthritis. I doubt that the inflammation in an athlete is significantly different from that found in a rheumatoid arthritis patient?
SWIM: But you did work with the Stanford swimmers. Are you saying it was your diet that gave them an edge? And what was the relationship between eating fish oil and your Zone diet?
Sears: Although my primary goal has been the development of dietary approaches to treat chronic disease by increasing blood flow and decreasing inflammation, I felt that the same approach should help improve athletic performance. I had the fortunate opportunity in the early 1990s to work with the Stanford swim teams to ask that question. My primary concern was to determine whether or not I could get elite athletes to follow the Zone diet and take fish oil., I knew if I couldn’t get them to follow that advice, I would have very little success with the average cardiovascular or diabetic patient. This was why my work with the Stanford swimmers wasn’t based only on the Zone diet, but also the use of fish oil to control eicosanoids.
As I’ve already stated, any time you can help an athlete increase blood flow and decrease inflammation, you will give them an edge. In addition, if you can stabilize blood sugar levels, they will perform better during workout or competition. Any dietary recommendations must involve a certain degree of common sense, backed by scientific studies. That means adequate, but not excessive amounts of protein; large amounts of fruits and vegetables; and suitable amounts of heart-healthy monounsaturated fats; and supplementing all this with long-chain, omega-3 fats found in fish oils.
For example, there are over 200 published studies demonstrating eating large amounts of fruits and vegetables is associated with a decrease in the incidence of heart disease ands cancer. On the other hand, there are no studies that show eating large amounts of starches have corresponding health benefits. In fact, several published studies from Italy have indicated that an increase in starch consumption is associated with increasing rates of cancer.
In light of this published data, it makes little sense to me to encourage individuals to eat large amounts of starches, such as bread, pasta and bagels.
The relationship of the Zone diet and high-dose fish oil is that the more you control insulin, the less fish oil you will need to control eicosanoids. This is why, every week, the Stanford swimmers would fill out an eicosanoids status report so I could individually alter their fish oil intake to maximize their eicosanoids levels.
SWIM: The Stanford swimmers who ate your diet did really well in 1992. However, without published research, this is anecdotal. Have you initiated any rigorous studies on swimmers and fish oil?
Sears: Those studies with the Stanford swimmers were not controlled because the coaches would not allow any of their athletes to be in the control group. However, as the Stanford coaches stated in a 1993 article in SWIM magazine, they could think of no other reason for their phenomenal success in 1992 other than the inclusion of the diet and the fish oil.
SWIM: Have the Stanford swimmers continued to use the diet?
Sears: To the best of my knowledge, yes.
SWIM: On page 213 you write: “I am still waiting for just one experiment to prove the hypothesis that consuming a high-carbohydrate diet for an extended period of time improves performance.”
In the book Sports and Exercise Nutrition by William D. McArdle, Frank I. Katch, and Victor L. Katch, Lippincott, Williams &Wilkins 1999, the following study is mentioned with a full-page graphic illustration: Helge,J.W., et al.: Interaction of training and diet on metabolism and endurance during exercise in man. J. Physiol., 492:293, 1996. In that study ten young men were fed either a high carbohydrate or a high fat diet for 7 weeks, during which their time to exhaustion on the cycle ergometer was measured. At 7 weeks those on the high carbohydrate diet were able to ride for 102.4 minutes, while those on the high fat diet were only able to ride for 65.2 minutes, a significant difference. At week eight the high fat group was switched to the high carbohydrate group. They were then able to ride for 76.7 minutes, while the group that stayed on the high carbohydrate diet was able to ride for 103.6 minutes.
How can you still claim there are no studies to support a high carbohydrate diet?
Sears: My statement in The Omega Rx Zone was based on studies with trained athletes, not untrained individuals. The above study used untrained individuals and a much higher fat diet (62%) than I would recommend. Studies over the past eight years from the University of Buffalo have demonstrated when trained athletes are switched to a lower-carbohydrate, and higher-fat diet; their performance is significantly enhanced as well as their cardiovascular profiles. This led the Buffalo investigators to remark that high-carbohydrate diets may be injurious to the cardiovascular health of trained athletes.
SWIM: A search on Medline for the past ten years showed only one study related to the Zone diet. Jarvis M , et al.J. The acute 1-week effects of the Zone diet on body composition, blood lipid levels, and performance in recreational endurance athletes. Strength Cond Res, 2002 Feb; 16(1):50-7. This study showed that the Zone diet used for one week did not offer any benefits. (1) Why haven’t any other studies been published? (2) Why haven’t any favorable studies been published?
Sears: The Zone Diet can be defined as a diet that maintains a protein-to-carbohydrate ratio between 0.5 and 1.0. Under this definition, a high-carbohydrate diet would be any diet that contains at has more than twice the amounts of carbohydrates compared to proteins. A high-protein diet would be one that has more protein than carbohydrate. This means that a Zone diet is neither high-carb nor high-protein.
In the past three years, numerous articles, primarily from Harvard Medical School, have been published comparing the Zone diet to high-carbohydrate diets when both contain the same number of calories. In every study, whether it has looked at insulin response, appetite suppression, metabolic response, lipoprotein levels, or fat loss, the Zone diet has always been shown to be superior. Since the word “Zone” was not in the title or abstract of the articles, a search of Medline would not have picked them up.
Regarding the article you mentioned, I can only speak from reading the abstract on Medline, which does not mention any of the experimental conditions used in their study. However, it is apparent that the investigators did not supplement the Zone diet with fish oil as I did with the Stanford swimmers, or maintain higher levels of fat as the Buffalo studies did.
SWIM: Most Masters swim practices are one to one and a half hours long at a moderate intensity. Wouldn’t we be utilizing our carbohydrates and fats somewhat equally?
Sears: At lower exercise intensities, the body will utilize more fat as an energy source. This is reflected in the lower respiratory quotient (RQ). The more moderate the intensity, the more fats are used to provide the energy to make adequate levels of ATP required for muscular contraction.
SWIM: Most competitive swimming events in a pool -- not counting the open water events -- are of a high intensity and short duration: let’s say roughly 20 seconds to 20 minutes. According to the above source, we would be utilizing much more glycogen for energy than fat. Apparently the rate of fat mobilization stays steady regardless of intensity, and therefore glycogen is utilized more. How would your diet help a competitive swimmer?
Sears: The amount of glycogen in an athlete’s muscle stores can only be exhausted by long-term, high-intensity events, such as in a two-hour or longer open water swim. In short-term bursts of high-intensity exercise, the rate-limiting step in performance is due to the build-up of lactic acid in the muscles, which is due to inadequate oxygen transfer to reduce lactic acid to pyruvate. This is why the Zone diet, if done correctly by using the proper amount of fish oil, can aid athletic performance because it can increase blood flow (and therefore oxygen transfer) by altering eicosanoids levels.
SWIM: Any final remarks that you would like to add?
Sears: Yes. The goal for any Masters swimmer is a longer and better life. The foundation for that is a healthy diet. In fact, your grandmother gave you all the dietary advice you need when she told you to do four things. First, eat small meals throughout the day. Second, consume adequate amounts of protein at each meal. Third, always eat your fruits and vegetables. And finally, take your cod liver oil.
The only difference between your grandmother’s dietary wisdom and the Zone diet is that instead of taking cod liver oil, I recommend taking enough pharmaceutical-grade fish oil to change the balance of your eicosanoids.
SWIM: Thank you very much.
Sears: Thank you. It was a pleasure.
For more information, click on: www.doctorsears.com