Doctor's Note

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  • Veguyan


    • Michael Greger M.D.

      What struck you in particular?

  • Toxins

    T. Colin Campbell, Caldwell Essylsten and the doctors of their kind appearing in Forks Over Knives claim that olive oil is not healthy. What are your thoughts on this?

    • foxfyr

      They are right on the money.
      And don’t limit it to simply Esselstyn & Campbell. McDougall, R. Vogel, L. Rudel, & myriad others agree.

      • Scott

        What about saturated fat in whole plant foods? Is that damaging endothelial cells to?

  • I’ve heard a lot of wishy washy info about olive oil too. It’s good for you…it’s bad for you, back and forth. I still choose it over all other oils but would love to learn more. How much is too much of this oil? Is there anything to be concerned about in using it? I can’t believe the bunny batter idea. That is horrifying!

    • Toxins

      The idea is to eat whole foods plant based and oil does not fit this criteria. Oil apparently damages your epithelial cell wall in your veins which keeps things running smooth and allows your blood vessels to expand and contract properly. T. Colin Campbell explains this on his lecture on “how to be heart attack proof”.

      • foxfyr

        Please see Caldwell Esselstyn’s “How to make yourself heart attack proof”.

      • Brent Naseath

        I’ve read Dr. Campbell’s material and Esselstyn’s material. They generalize studies on a few oils to all oils. Aside from those who tout the benefits as “an expert” who has studied what everyone has written, there are many people who make comments on all of the videos and articles about coconut oil how they had their HDL and LDL tested after starting on coconut oil and they improved dramatically. Personally, my doctor said I have better cholesterol levels than a 25 year old and I am almost 60, but I am also a raw vegan so that doesn’t prove the coconut oil I take helps. If you (or anyone else reading this) can show me a study where they did the same tests as on animal fats etc. on cold pressed virgin coconut oil and demonstrated that it actually damaged the epithelial cells rather than just extrapolating from tests on other oils, I would greatly appreciate it. Please believe me, I am not saying this to challenge anyone’s statements, I just am not sure such generalizations are always valid and I would like to see a study or experiment validating their assumptions. Thanks in advance!

  • yurple

    If one is going to eat oil to some degree, what are the best and worst oils to eat? This video seems to indicate that olive oil is not harmful, but is it helpful? If not, where did that widespread idea come from? How about other oils? Please advise.

    • Toxins

      Excellent Questions yurple and maybush1!
      Although this video says olive oil had no effect on health, one must consider other studies as well and how one defines health. All oils are basically liquid fat. They are empty of phytonutrients, vitamins, minerals and fiber. They contain only fat and calories. Oil is the definition of empty calories, food without nutrition. Check out this excellent short video with Jeff Novick discussing this topic, specifically on olive oil.
      If you don’t care about fat, and are more interested in oil’s damage, Dr. Caldwell Essylsten provides this answer. According to Caldwell Essylsten, all oils, including olive oil, cause damage to your endothelial cells within your blood vessels. These cells are very important, as they are responsible for contracting and expanding your blood vessels as well as keeping your blood running smoothly. A damaged endothelial cell wall means low performance during physical activity as well as an increased risk in heart attack since a healthy endothelial cell wall does not allow arterial blockages to form. You can see that video here Nuts, on the other hand, are extremely nourishing and health promoting. They provide you with the necessary fat intake you need for proper nutrient absorption and health. Check out Dr. Greger’s video about it here:
      Olive oil can be considered the healthiest of the oils, but it is not health promoting. The idea came from studying the Mediterranean diet. But not just any Mediterranean diet, specifically in the island of Croatia. They ate a primarily plant based diet with some meats and used olive oil in their foods. They were much healthier than Americans at the time and people were wandering why this was so. To mimic them, people began to use olive oil (the whole “plant” idea didn’t transfer over I guess). This was done in the earlier years of the 1900’s. Now, Croatia is much more Americanized and they are getting just as sick as the average American.

      • GD

        Correction: The island of “CRETE”.
        Croatia is not an Island.

      • foxfyr

        Actually, in most of Vogel & Rudel’s studies, canola oil is found to have slightly fewer deleterious effects than olive oil (which does result in endothelial cell inflammation and reduced brachial flow).

        But before anyone run for canola oil, while polyunsaturated fats may have fewer adverse effects at low concentrations than either mono or unsaturated fat, at higher concentrations they seem to be just as bad as the others.

        And while one can debate how much endothelial cell inflammation results, none of the studies show any fat to avoid causing inflammation in situations where inflammation was not present, or to reduce existing endothelial cell inflammation.

        And additional studies show the Persin content in avocados to overwhelm and to negate any discussion regarding the fat content in avocados…

        Thus while the total synergetic effects of the total contents of nuts such as walnuts may have a net positive effect on health, there still seems no solid evidence to suggest that more than a target of about 10% of fat from whole plant sources is beneficial.

  • yurple

    Please advise about consuming oil, in general. If one is going to consume any, which are the best? Worst? I see this video says olive oil isn’t harmful, but is it helpful? If not, where did that widespread idea arise? How about other oils? Safflower? Sunflower? Canola (also touted as good)? Corn? Soy? What about if organic? Please advise and thanks.

    • gina

      all oil is bed for us

  • maybush1

    Good questions Yurple. I would like to know more as well. Thanks.

    • Toxins

      Hello Maybush! Please see my comment above that answers your question

  • maybush1

    Hi Toxins, but Dr. Greger mentions in this video, as Yurple observed, that eating high fat plant-based oils “such as olive oil” is not harmful on the epithelial lining and that high fat nuts, such as walnuts, are actually beneficial for them.

    So, Dr. Greger says that there is NO harm in consuming olive oil, while Dr. Campbell says that it damages the epithelial lining of arteries (based on animal studies?). So, again which is correct…for *humans*?

    • Toxins

      Interesting observation Maybush1!
      To answer that, have you heard of the brachial artery tourniquet test? It measures the blood vessel expansion in your arm after a meal. They cut off the circulation for 5 min. and then release to see what happens. If it was an unhealthy meal, then your blood vessels do not expand. Normally they should inflate allowing a surge of blood flow. You can read about who fails this test here and sure enough, people who consume olive oil experience endothelial cell damage. Their vessels do not expand normally. This happened with all oils. Dr. McDougal acknowledges this same fact as well So it seems olive oil is not health promoting based on the brachial artery tourniquet test. Check out this video by Dr. Greger that show some foods that will help out with some of that excess fat!

  • maybush1

    Hi Toxins and thanks for the reply! The BART test seems like a promising test to perform, although the oil tests seem to be short snapshots in time (that shows BART tests soon after consumption of olive oil-enriched foods). So, I’m not sure how accurate a BART test is in forecasting the deleterious effects of olive oil on the arteries over a long time.

    It’s fascinating information nonetheless!

  • Vallis

    Is there any opinion//science on Avocado oil (like for salad dressing? Is it a processed fat junk food to be avoided as well?

    • Toxins

      Vallis, remember that oil is purely fat without nutrients. If we had Kale oil, its the fat from the kale without any nutrients. I believe it qualifies as junk food since it is empty calories.

    • foxfyr

      Go watch Dr. Greger’s “Are avocados good for you” and think about how or why Persin in the oil would be any better for you than Persin in the avocado…

      No, per Vogel’s brachial flow tourniquet tests, Rudel’s extensive long term studies, nor Esselstyn’s clinical studies, etc., does ANY oil avoid the problems.

      ALL oils are processed foods!

  • Chris Steele

    I think the more important message Dr.Greger is trying to point out is how nuts and avocados are NOT detrimental to our health and many of the extreme fat-phobic vegan health gurus like Jeff Novick may actually have it wrong telling people not to eat nuts or avocados.

    • foxfyr

      Sorry, but this is NOT supported by evidence!
      Vogel conclusively shows that ALL of the fats (& oils) result in reduced blood flow via the brachial flow tourniquet tests, and Dr. Greger goes on to dispel the nonsense that Persin containing DNA damaging (to use an understatement) avocados are good for you in “Are avocados Bad for you”, nor do the Myriad studies on the effects of fats on causation of endothelial cell inflammation indicate that ANY percentage of fats from WHOLE plant foods above ~10% are healthy.

      So, when does someone ask if the amazing magical coconut oil is exempt as well?

    • Ellen R

      Wow Chris, you should watch Jeff Novick’s DVD on nuts or listen to his actual lectures. I saw him at the McDougall program & bought his DVD. He actually recommend 1-2 servings a day of nuts/seeds/avocados and depending on the person, up to 4 oz/ day. I would not call that, fat-phobic.

  • Charles

    I’ve just read McDougall’s book “The starch solution”, where he recommends to avoid completely all kinds of oils, including olive oil. According to this video olive oil would have no positive or negative effects in your health. So, what is the conclusion in this point, given that olive oil is a great flavor in my meals, I would like to know if I sould give up the consumption of this food.

  • What is your take on the recent NEJM article about the Mediterranean Diet?
    It seems to be stirring up some controversy.

    • Check out Dr. Ornish’s take:

    • foxfyr

      The postprandial effect of components of the Mediterranean diet on endothelial function, R. Vogel MD, et al.

      “Conclusions: In terms of their effects on postprandial endothelial function, the beneficial components of the Mediterranean & Lyon Diet Heart Study diets appear to be the antioxidant-rich foods—vegetables, fruits, & their derivatives such as vinegar, & omega-3-rich fish & canola oils—NOT olive oil.

      Canola oil may share some of the unique vasoprotective properties of other omega-3-rich oils, such as fish oil.

      Dietary fruits, vegetables, & their products appear to provide some protection against the direct impairment in endothelial function produced by high-fat foods, including olive oil.”

      Thus, the oil is not providing any protective benefit, rather it is the effect of the whole anti-oxidant rich plant foods that are doing the heavy lifting. Just think how much more effective they might be if some of the damaging refined fat sources are removed?

  • Foxfyr

    So here high fat Persin containing avocados are healthy?

  • j

    Seek Jesus and HE will solve all of your problems, nothing else will. God Bless.

  • barbarabrussels

    How to best fry an onion?

    • Thea

      barbarabrussels: Must the onion be “fried”? I chop up my onions and then microwave them for about 3-4 minutes. No oil or anything needs to be added. The onions come out translucent and sweet – just as if they had been sauteed. But missing the oily mouth feel of course. It not only works great in terms of results, but it is much easier/less hassle.

      Just an idea for you.

      • delana

        Doesn’t the microwave damage the cells? I’ve read a lot of bad things about microwaving, that it damages proteins and changes fatty acid structure, and makes food less healthy… so I’m hesitant to use the microwave too much

        • Thea

          delana: Sorry it took me so long to reply.

          Concerning microwaving food: I know that there is a whole lot of concern on the intranet, but I have not seen any legitimate concerns myself. If you are interested learning more about why I am not concerned, check out this great page:

          Hope that helps.

  • g

    unable to hear any of the presentation due to bad audio

  • Clare

    I just watched one of your videos about avocado damaging dna and here you say avocado is good so now I am confused.

    • Shaylen Snarski

      what video was this?! Are you sure he wasn’t talking about the extracted oil?

  • Amy N

    Is there any scientific research to show that oil pulling is legit?

    I recently stumbled across some facebook links showcasing all the amazing health benefits. In case you haven’t heard about it, oil pulling refers to putting a tablespoon of oil, any kind but preferably coconut, into your mouth & swishing it around for 20 minutes. Then you spit it out & brush your teeth. All I can imagine is that coating your mouth with lard & then brushing it away offers textile contrast, tricking your brain into thinking your mouth is cleaner.

    If there are any studies showing that oil pulling really does increase oral health, I would love to know.

    • Cheile61

      I’m really interested to know this too; I have tried it and it did feel nice. Coconut oil also did genuinely alleviate a severe tooth ache caused by an infection I had, but Garlic was sometimes equally effective (Though slower acting and less pleasant?) I still think there may be some useful functions for coconut oil in moderation, but I think cooking every meal in it is probably a very bad idea.

  • We know that olive oil triggers desaturase, which converts palmitic acid — a bad saturated fatty acid that the WHO places in the same category of carvdiovascular disease risk as transfats — it converts it into palmitoleic acid, a very beneficial monunsaturated fat. Olive oil is what makes the mediterranean diet work! Palmitoleic acid is like olive oil on steroids!

    • Shaylen Snarski

      Thank you for this info!! I was just asking about why studies show the extra virgin olive oil rich Mediterranean diet is so beneficial to heart health!

  • Russell

    Is there any science suggesting we can eat an excess of good fats, or are good fats similar to vegetables, in that, it seems, we can shamelessly indulge to our heart’s content? In other words, is there a possible risk to having 150 or 200 grams a day of nuts, olive and canola, and avocado?

  • baggman744

    Olive oil neutral? Whatta relief! I can’t see life without it. Its the only fat I buy. So, I’ll continue to have my salads & veggies, with a little EVOO, lemon juice or vinegar, and some chopped walnuts.

  • Mark
  • vegan2u

    I have a slight beef with what Dr Essylsten states during his presentations, while I have high respect for the man, I recently saw him totally nullify any potential good in green smoothies that may contain some fruit. While I understand the pulverizing of food makes it easier to digest which can trigger insulin spikes. While this is true to a certain degree, how many parents out there are pissed off by those types of comments that effects what they are trying to do for their kids? First of all, kids tend to exercise more and they can burn off the sugar. Personally, I use so many high fiber foods in my kids smoothies, I’d be surprised that this is damaging to any degree. No Oil! No Oil! How many times do you hear this, that is crap, even Dr Greger recognizes that nuts are a healthy food for us. If he is addressing only heart attack patients, then he needs to say that, he also flip flops on this topic, I have also heard him state that Chia seeds or Flax seeds are OK on your morning oatmeal. Which is it? They have oil, Dr Furhman even states that blueberries help stave off sugar spikes. He needs to relax and encourage people that are trying to do the right thing by their kids and quit being such a naysayer to everything he may not see as helpful.

    • Thea

      vegan2u: You wrote, “No Oil! How many times do you hear this, … even Dr Greger recognizes that nuts are a healthy food for us.” I have read Dr. Esselstyn’s work and also listened to several of this talks. It has always been clear to me that, “NO OIL!” means no processed/extracted oil. He means, no peanut oil. He’s not talking about the peanuts. He means no corn oil. He’s not talking about the corn, etc. And if you watch enough videos on NutritionFacts, you will see that Dr. Greger agrees that extracted oils are unhealthy for everyone.
      Thus, there is no flip flopping when Dr. Esselstyn talks about the benefits of flaxseed or chia seeds. Those are not extracted oils. Dr. Esselstyn even has a recipe that includes walnuts in his book about preventing heart disease. He just makes it clear in that book that for people with heart disease, they should really be careful about how much fat they take in. Thus maybe such people should skip the recipe. The distinction between most nuts and flaxseed/chia seed is the giant amount of omega 3s in flaxseed. So, again, Dr. Esselstyn is being consistent. (Though this is an area that Dr. Greger and Dr. Esselstyn might disagree. I don’t speak for Dr. Greger, but based on his videos and recommendations, I think Dr. Greger might recommend 1 ounce of nuts even to heart disease patients. Though I don’t know.)
      I hope this clears up the confusion.