Bad fish doesn’t exactly have a good reputation to begin with.
When it comes to food poisoning, eating fish past its prime is almost legendary in its power to make people sick. But seafood is rightly considered “brain food” — and fresh, uncontaminated fish and seafood products are among the better things people can have in their diet. Even vegetarians often make seafood the one nutritional region where personal health gets to trump their cross-species ethics.
Omega-3 fatty acids, which seafood provides in abundant amounts, are a topic we’ve covered many times previously — and it’s been recommended by past guests that as much as 5 grams of supplemental fish oil per day might be advisable, if you’re not getting much seafood in your regular diet.
Not so fast, says Chris Kresser
While Omega-3 fatty acids live up to their reputation for brain and body health if taken in a natural, unadulterated form…that can be a big “if,” according Chris Kresser, M.S., L.Ac. (also the host of Revolution Health Radio). And sometimes the supplemental alternatives to getting these food in our diets can end up doing more harm than good — being pro-oxidative and pro-inflammatory when our goals in eating them is often just the opposite.
Studies like this one show that many over-the-counter Omega-3 supplements contain partially-oxidized lipids in amounts great enough to make them not only a waste of money, but counterproductive in improving your health. What is a person to do?
According to Kresser, in both this interview and the recently-updated, thoroughly referenced post about fish oils on his website, the surest-fire way of ensuring that you’re getting the Omega-3’s your nervous system needs without taking in unintended, pre-oxidized chemicals is comparatively simple: Skip the supplements, go with honest-to-goodness, natural seafood.
For most people, two meals per week containing a helping of fatty, cold-water fish is just what the neurologist ordered. Kresser is also a big proponent of shellfish. But rather than re-hashing the dietary recommendations here — which includes interesting advice about the “smoke point” of various cooking oils — give the episode a listen.
This episode is a slightly shorter one, but chunks of this interview branched into other topics — Kresser has a wide range of expertise — and we’ve saved some bits for future episodes, so add a mental “to be continued…” bookmark as you listen.
|0:22||The controversial side of Omega-3 fatty acids|
|1:32||This Week in Neuroscience: A biocompatible, transparent therapeutic window to the brain|
|4:52||The audience interaction section|
|6:43||Considerations when taking Omega-3s|
|7:22||Introduction to Chris Kresser|
|7:56||Episode 166: Omega-6 Fatty Acids with Dr. Chris Masterjohn and Episode 51: The Aquatic Origins Of Your Brain|
|8:22||Enthusiasm for Omega-3s and dangers of relying on supplementation|
|10:20||What is the worst outcome that could come from supplementing with fish oil?|
|13:33||Viable alternatives for vegans and vegetarians|
|14:40||Some of the most important foods for brain health|
|16:04||Dr. Michael Crawford’s aquatic ape theory|
|18:51||The effect of omega-6 intake on omega-3 conversion|
|19:49||Rules of thumb for balancing the omega fatty acid ratio (eat real food!)|
|23:36||What kind of cooking oil is best to use?|
|28:46||Clinician Training Program at the Kresser Institute|
|29:10||Ruthless Listener-Retention Gimmick: Walking Affects Mood, Even When Not Expected To|
Jesse Lawler: So we've had a couple of episodes on the virtues of omega-3 fatty acids in fish oil and fish oil supplementation as well as of course real-life fish or real-dead fish the kind that you might be eating. But as with most things of course there's pros and cons for how you get these substances into your body. It's not just what they are but how you get them there. What's coming along for the ride and for omega-3 there's a lot of different things to consider. There's the natural fish. It might that have mercury or other seaborne toxins or if we go with the supplements might we be missing out on something that maybe hasn’t even been identified but it's going to be helpful as well. If we go with the non-meat source something that's purely vegetable, will we have the same level of bio-ability? Will that be a viable alternative to eating something that comes from an animal source?
A couple of years ago Chris Kresser wrote in an article entitled, "Should you really be taking fish oil?" Just to the reason to follow-up this current January, I caught him for a conversation. Chris Kresser is one of the leading thinkers and the voices in the Paleo and Ancestral Nutrition Movement. He is the author of the book "The Paleo Cure" along with more lengthy and highly sourced online blog post that you can shake a stick at. His website, not surprisingly is ChrisKresser.com and we're going to be talking here about fish oils inflammation oxidation, the necessity of getting fat into your diet and also some warnings and best practices on how to actually do that effectively. This is a nice follow-up episode of the conversation that I had a few weeks ago with Dr. Chris Masterjohn and also in many ways a follow-up to episode number 51 -- still one of my favorites in which I spoke with Dr. Michael Crawford from the Imperial College London.
A fatty oceanic interview is coming up with both some warnings and also some recommendations on how to actually go about food preparation. We talk about cooking oils and how much of various things to eat. But with no further ado, let's jumped in with Chris Kresser.
Chris Kresser: Early on, there was a lot of enthusiasm about fish oil and the party line was, "Hey, fish oil can solve a lot of problems that are related to a crappy diet. You eat a crappy diet, you just fish oil yourself out of that crappy diet and you'll be okay." It's a little bit of an exaggeration but I think there were some truth to how that was portrayed in the media. Just take some fish oil and that will reduce the inflammatory load that you're causing by the following inflammatory diet and lifestyle. I think that's actually a key-point because that's one of the dangers of relying too much on supplementation because there's this compensation effect that happens where you think, "Oh I'm taking all this supplements so I probably don't need to pay as much attention to the other things that are important for health."
That's actually mentioned in some of these studies where fish oil was associated with poor outcomes. They actually speculated that in some cases it might have been related to what I just mentioned. So you know initially there was a ton of enthusiasm about fish oil particularly its benefits for cardiovascular disease but also other conditions, brain health, skin conditions, arthritis, and really kind of any inflammatory disease. But over the last, I'd say five to ten years there's been a lot research including some very, long-running randomized clinical trials and some really good med analysis that have really questioned those disputative benefits of fish oil and either found that there was no benefit or in some cases even potential harm. I wrote an article in 2015 highlighting some of these claims and I recently updated it in 2017. Just now in January with even more recent evidence that threw these claims into further doubt. I think where we're at is essentially in a big re-evaluation of the initial enthusiasm for fish oil and now finding that in the case of many conditions particularly cardiovascular disease there appears to be no benefit and possibly even harm associated with larger doses.
Jesse: What is the worst outcome that the person might expect if they are supplementing with fish oil other than a hole on their wallet?
Chris: Fish oil consist of long-chained fatty acids EPA and DHA and these fats are extremely fragile and susceptible to oxidative damage and that can happen outside of the body just in the capsule itself because they are susceptible to light and heat. So if the fish oil isn't processed very carefully, oxidative stress can be introduce at any point in that processing and the fish oil in the capsules themselves can become oxidized. There have been recent studies that have shown that the top brands, the three top selling fish oil supplements in the US were shown how oxidation levels are of up to four times higher than what those are recommended to be safe which is pretty significant.
These oils can also become oxidized in the body. If you're oxidative stress levels are high because of inadequate physical activity and poor diet and all of the other things that cause oxidative stress related to modern diet and lifestyle. Those long-chained omega-3 fats can oxidize in the body. In either case what's at stake is that oxidative stress is essentially linked to virtually all chronic inflammatory diseases from heart disease to arthritis to dementia and Alzheimer's to autoimmune diseases of all types. If you're consuming oxidized oils especially at high dosage, I don't think the risk is as significant if you're taking a moderate dose like 500mg.
But at three grams a day which some mainstream organizations and practitioners of both conventional and alternative persuasions have recommended or higher even then there's a real risk that you could be increasing your inflammatory load and we don't need that because we already have so many challenges in that regard.
Jesse: Would there ever be any trade off as far as maybe you're doing something that is not necessarily great for you overall physiology circulatory system in your heart but because omega-3's are still used in myelination of nerve cells in the brain that it might be worth it for the brain even if you're overall physiology might take a hit or are the brain and heart sort of always on the same side?
Chris: I would say it's pretty hard to separate them out because the brain is part of the whole vascular system in the body. It is what carries blood to the brain and blood has everything the brain needs to function properly and it is true that omega-3's particularly DHA are absolutely crucial for brain health so I want to be clear here. The message is not that omega-3 and EPA and DHA are not good for you or good for the brain that's absolutely untrue. The message is that obtaining those fats from a purified concentrated fish oils that may have become oxidize is not necessarily the best way to do it.
The strong message in my article was eat fish and seafood, absolutely. Do that because studies consistently a strong positive association between fish and shellfish intake and all kinds of benefits including brain health. It's not about avoiding EPA or DHA, it's about getting it from food. That's how we evolve to obtain this nutrients is from in the context of a whole foods diet not in concentrated oils.
Jesse: For people that might be vegan or anti-fish for whatever reason, are there any viable alternatives to supplementation?
Chris: Yes, there are microalgae. Algae supplements contain DHA, that's actually where fish get DHA from and why fish have high level of DHA in their flesh it's because they consume algae. You can get microalgae supplements that contain DHA if you're vegan or don't want to consume fish for any reason. But I should also point out that for those who are not vegetarian and they're willing to consume fish but just don't because it's not top of mind and maybe they don't like fish that much. There are a lot of other benefits to consuming seafood above and beyond the EPA and DHA including highly absorbable source of protein and selenium and vitamin D and zinc and other nutrients that are not necessarily easy to obtain even from other foods in the diet. Just something to consider.
Jesse: It's worth finding a couple of seafood that you can stomach even if it's not necessarily your favorite thing because there are so many benefits there.
Chris: Exactly and I would say if we're talking about brain health, if you were to ask me what are some of the most important foods for brain health, I would put shellfish in the top three for sure. Shellfish and organ meats are really the two most nutrient dense sources of food when you look at pound for pound or ounce for ounce. They're extremely rich in a variety of nutrients that are not well-represented elsewhere in the diet like Vitamin A. By Vitamin A, I mean the real active form of Vitamin A, Retinol. Retinoic Acid not beta-carotene which is in carrots and red peppers and is a precursor to Vitamin A but actual Retinol and that's important because some people don't make the conversion from beta-carotene to Retinol very well.
So eating pre-formed Vitamin A which only really occurs in organ meats and shellfish in any significant amount maybe pasteurized dairy to a lesser amount but also copper and zinc which are both important nutrients for brain health and all of the B vitamins which are important for methylation and neurotransmitter production and metabolism. So when you look at like organ meats for example with copper, all you need to do is eat one, three ounce serving of oysters and you've met your weekly allowance for copper and that's true with a number of other nutrients. Iron of course is very important in nutrient for brain health and organ meats and shellfish. Shellfish would be included in that when we say eat seafood for the omega-3 but there is a lot of other reasons to consume shellfish and seafood.
Jesse: A couple of years ago, I spoke with Dr. Michael Crawford and I'm not sure if he originally proposed this theory or he's just one of the major advocates of it. But there are a lot of reasons to think that rather than having turn from hominid ancestors of humans into human on the plains of Africa. It was probably more on the seashores of Africa just because that was probably the only environment where the available diet would have provided enough omega-3 where early humans wouldn't be able to have their brains triple in size simply because the foods that would provide those oils wouldn't have been available in land on the continent.
Chris: Yes. It is a fairly prominent theory of human evolution, hominid evolution and I think there's a lot to be said for it for sure. I mean DHA and EPA. In nutrition the standard idea is that the precursors to EPA and DHA, alpha-linolenic acid essential and by essential I don't just mean really important. I mean, essential in the context of nutrition means they must be obtained from the diet because the body cannot synthesize them on its own so they have to be obtained through eating. But there's a pretty compelling argument advance by Dr. Chris Masterjohn and nutritional scientist and others that suggest that the reason alpha-linolenic is essential is not because that fatty acid which is found in things like walnut and flaxseed and plant foods. It's not because alpha-linolenic is essential itself, it's because what it’s ultimately converted into which are EPA and DHA, the long-chained omega-3 fats you find in fish and algae are essential. If we obtain EPA and DHA from fish we don't need alpha-linolenic acid because what we really need is the EPA and DHA and so that theory evolution that people who advocate that saying, "Well, if EPA and DHA are essential then wouldn't it make sense that we evolve in the context where we had access to those foods,
Jesse: Yes. I find that pretty persuasive. I'd like to hear what the detractors of that theory -- what their counter-argument is.
Chris: Yes. I haven't seen any convincing counter-arguments myself. I mean, I think that this is pretty convincing and it's also interesting to know that the conversion of the plant-based forms of omega-3 like alpha-linolenic acid found and flax and walnuts that I just mentioned is extremely poor. According to some studies, less than one half percent of alpha-linolenic acid gets converted into DHA which is ultimately what we're looking for from a brain health perspective or any other health perspective which means you have to be eating a pretty considerable amount of those plant-based omega-3 in order to convert sufficient amounts to DHA and that's assuming you have adequate nutritional status of other nutrients that are required for that conversion which many people do not.
In practice it becomes problematic for people to convert those plant-based omega-3 into the long-chain omega-3 and the other issue with that is that a high intake of omega-6 fats suppresses that conversion. Omega-6 fats are things that they're found in a lot of process and refined foods like soybean oil and corn oil and sunflower and sunflower oil. If you pick up any package food in the supermarket, it's going to have those oils. If you go out to eat at any restaurant, all of the food is cooked in those oils. It's really hard to -- even if you eat a healthy diet to keep your omega-6 intake so low that it doesn't interfere with the conversion of those plant fats into DHA and EPA.
Jesse: Because as I understand it, basically the conversion of both is using a lot the same enzymes within the body so if you're over-stuffing the incoming pipes with Omega-6 is there are just aren't enough enzymes available to do the conversion of the precursors for omega-3.
Chris: That's right. It's a competitive inhibition and some researchers believe that that's one of many factors that causes our modern diet to be inflammatory.
Jesse: Do you have any rules of thumb for people as far as balancing the types of fats that they're taking in or whether it's fully formed omega-3 or omega-6 within their diet or if you're eating whole foods from animal sources. Does that problem of keeping the ratio perfect kind of disappear?
Jesse: Yes, that's a great question. Early on I was somewhat persuaded by study suggesting that the omega six to three ratio should be kept around two to one or four to one which is an alignment with the historical ratio. In other words, if you look at ancestral population’s contemporary hundred gathers, you see that they've generally ate somewhere between an equal amount of omega-6 and three to maybe four times the amount of omega-6 relative to omega-3 and that was the historical norm. But today that can be anywhere from nine to one to 25 to one in the US so it's a huge change, absolutely gigantic change mostly mediated by the dramatic increase and consumption of industrial seed oils like soybean or oil which is in almost everything.
Early on it seems that that ratio was a big driver of the chronic disease epidemic. As I began to dive further and further into the research and believe me there's a lot of controversy on this issue still. You'll see a lot of peer reviewed studies on both sides but I began to believe that the denominator is the most important thing. It's more important than the numerator. So the denominator in this case is omega-3 intake and my current understanding and recommendation is that you don't need to worry so much about omega-6 in the context of whole food. For example, if you eat an avocado that's a huge hit of omega-6 and same with nuts, they're very high in omega-6. Chicken skin is high in omega-6 . I don't really believe you have to worry about that. What I do think that omega-6 in the form of industrially processed seed oils may be problematic.
One reason for that is that it is probably more susceptible to oxidative damage which we already talked about earlier because of how it's processed and refined. Also it doesn't occur in a natural context where other nutrients like antioxidants are present. So when you eat omega-6 in whole food you're also getting antioxidants that could potentially limit the oxidative stress that might be caused by a higher intake of those fragile oils. But when you're consuming industrial seed oils, those are really purified and refined and don't have any other nutrients so you're just increasing your overall intake of fragile, unsaturated fat without necessarily increasing your intake of antioxidants that would be deal with that. So my current thing is just eat real food, that’s what I generally tell people. Don't worry about the omega-6 in real food but make sure to consume depending on your weight and activity level and calorie intake around 12 to 16 ounces of cold water fatty fish or shellfish each week or the equivalent amount of DHA that you would get from algae if you are vegan or opposed or can't or won't eat seafood for any reason.
Jesse: Do you have any rules of thumb for how to define real food? Something you can explain to a six or seven year old.
Chris: Yes. So like a can of wild caught salmon for example is typically somewhere between five and seven and a half ounces. If you eat two of those a week, you would be doing pretty well or a fillet of salmon that you might get at a restaurant could be anywhere from six to eight ounces typically. So if you ate a couple of those a week, you'd be doing pretty well. Or you could eat a couple of three ounce servings of oysters. If you go to whole foods there are smoked oysters for example in olive oil and you could eat a ten of those along with maybe some salmon once a week and that would be sufficient. So any of those combinations would be adequate.
Jesse: What about cooking oils for food? I know that there is lots of things to be said about that and maybe that's a deeper topic but since people are going to be using some form of cooking oil. Do you like using the dripping of fats from meat? Do you like things like olive oil? Where should people be thinking there?
Chris: With cooking you always need to consider the smoke-point of the oil and that is essentially the point at which oil begins to oxidize and from a practical perspective it's the point at which you start to see smoke. If you've ever like put oil in the pan and then forgot about it and come back you see smoke coming way up, that oil is becoming oxidized and it's not good to eat oils that way.
There are charts online. You can search for smoke-point of oils but the oils that have the highest smoke-points are olive oil that is not extra virgin so actually just somewhat refined olive oil. It's not a popular choice, it's actually even really hard to find in a store but that has one of the highest smoke-points and that's a good cooking oil. Algae oil, this is kind of new oil that's come on to the scene. It's almost exclusively more on saturated fat which is more stable than the polyunsaturated fat which means it has a pretty high smoke-point -- that's a good oil to cook with. Avocado oil and macadamia nut oil, smoke-points are relatively high. Expeller pressed coconut oil so again not extra virgin which is what most people will typically buy. But expeller pressed which means it's been refined but it's naturally with an expeller instead of chemically refined.
There are two advantages to cooking with expeller pressed oil, or three. One is that it doesn't have a strong coconut taste which some people don't like. I personally don't like all my food that taste like coconut so dishes that are made with extra virgin coconut oil for that reason, so that's one. Number two has a significantly higher smoke-point than extra virgin coconut oil, and three is it’s a lot cheaper. You can buy it in like a gallon size and just keep it on a cupboard and transfer them to smaller jars, that's what we do. Then there are other, ghee, which is butter oil essentially. The fat with all of the proteins and everything else removed from butter. Ghee has a relatively high smoke-point and is a good oil to cook with. For roasting vegetables which we do at not as high of its temperature as we would for sautéing for example. We liked to use lard, pasteurize lard and pasteurize duck fat. Those fats impart a really unique texture to food and vegetables and anything that you would roast in the oven.
Most liquid oils make things soggy. If you roast vegetables in them and use liquid oils they'll become a little bit soggy but if you use duck fat or lard that doesn't happen. They stay dry and crisp and relatively light and fluffy which might be a kind of counterintuitive to people until you realize that the primary fat that's used to make pie crust traditionally is lard for that reason because it has that flaky light texture. It's kind of like use the right fat for the right temperature and the right application.
Jesse: How did lard get such a bad name in the Western world?
Chris: I don't know. It's really interesting especially because lard has a lot of monounsaturated fat which is really when you think about it -- I can't think if a single dietary approach or philosophy that doesn't think that monounsaturated fat is good. Lard actually has more monounsaturated fat than saturated fat. It does have a significant amount of saturated fat. For example, three ounces of lard has I think something like 35 grams, and monounsaturated and 27 of saturated, and 9 grams of polyunsaturated.
So yes, it is a significant source of saturated fat but it's got more monounsaturated fat. I think it became dehumanize because it does have saturated fat and because it kind of represented an older more traditional approach to diet and food that use this traditional fats like lard and tallow and butter and duck fat. When the whole saturated fat and heart disease connection which has been also thrown into question was the status quo then all of those traditional fats that have a relatively high saturated fat content became the villains. Somehow people convince themselves to eating Crisco which if you open the jar and put it in your garage, rats won't even touch. It's healthier than eating duck fat or lard.