Doctor's Note

If you haven't seen it, or need to brush up, the carcinogen-blocking effect of phytonutrients to which I refer was covered three days ago in Prevention Is Better Than Cured Meat. And for more on crazy things food industries say, check out Heart Attacks and Cholesterol Agribusiness Sees It Differently, Egg Industry Blind Spot, Dietary Guidelines: Corporate Guidance, Dietary Guidelines: Pushback From the Sugar, Salt and Meat Industries and Is Pomegranate Juice That Wonderful?. This video is the second to last video in my 3-week series that started with Doping With Beet Juice and will end tomorrow with a video entitled "So should we drink beet juice or not?" Thanks for sticking it out with me! Now you just have another 1500 or so other topics to enjoy.

For some context, please check out my associated blog post, Using Greens to Improve Athletic Performance.

  • Michael Greger M.D.

    If you haven’t seen it, or need to brush up, the carcinogen-blocking effect of phytonutrients to which I refer was covered three days ago in Prevention Is Better Than Cured Meat. And for more on crazy things food industries say, check out Heart Attacks and Cholesterol Agribusiness Sees It Differently, Egg Industry Blind Spot, Dietary Guidelines: Corporate Guidance, Dietary Guidelines: Pushback From the Sugar, Salt and Meat Industries and Is Pomegranate Juice That Wonderful?. This video is the second to last video in my 3-week series that started with Doping With Beet Juice and will end tomorrow with a video entitled “So should we drink beet juice or not?” Thanks for sticking it out with me! Now you just have another 1500 or so other topics to enjoy.

  • http://twitter.com/MacSmiley MacSmiley

    Is it just animal fat that inhibits the protective Vitamin C, or does cooking high-nitrate veggies with oils or eating them with nuts, avocado, etc. cause the same problem?

    • Michael Greger M.D.

      It’s easy to get confused between nitrites and nitrates (and all the more confusing, probably, seeing only 2 minutes or so of the story every day)! If, however, you go back and watch this series through, you’ll note that it’s the nitrites (with an “i”) that turn into carcinogens (a process that is blocked by phytonutrients in the absence of fat). Nitrites enter your body two ways, through processed meats directly when you eat them (and so the fat in the meat undermines any phytonutrients added to the meat) or hours after you eat a meal of high nitrate (with an “a”) vegetables through bacterial action on your tongue (again it might be good to go back and review). So we need fat to maximize our absorption of the carotenoids in greens (so add some nuts or seeds to your salad) but then hours later once the nitrates make it back into the mouth and produce nitrites, that’s when we should have no fat in our stomach.

      • BPCveg

        Dr. Greger: I have a follow up question to your response to MacSmiley, namely:

        How can one ever time these digestive steps so accurately to ensure that there is “no fat in our stomach” when “the nitrates make it back into the mouth and produce nitrites”?

        Are you implying that after a meal containing nitrate rich plant products that we estimate the time it takes to reach our mouth and then never consume any fat at that time?

        This all sounds very difficult and prone to error!

      • http://twitter.com/MacSmiley MacSmiley

        Ahhh. I just reviewed the video “Priming the Proton Pump”.

        The key is the fact that the bacteria on our tongues do not convert the nitrates into nitrites while we are initially chewing our nitrate-srich green leafies. Our bodies put the nitrates back into our mouths via our saliva later on hours post-mealtime! THAT’s when the nitrates get converted into nitrites, reabsorbed when we swallow our spit, and THEN converted into nitric oxide!!

        BRILLIANT!

        Now I can see that medications that cause “dry mouth” are affecting more than our oral health!

        • http://twitter.com/MacSmiley MacSmiley

          Now it makes even more sense when Dr Fuhrman says not to snack on nuts between meals, but to eat them with meals, beyond initial nutrient absorption enhancement. That way there won’t be any fats in your stomach when the nitrates make there 2nd appearance.

          • Thea

            re: “Now it makes even more sense when Dr Fuhrman says not to snack on nuts between meals, but to eat them with meals…”
            MacSmiley: Thanks for this comment. Just the other day, someone was telling me that Dr Fuhrman says what you wrote right here. I didn’t say anything in response to this person, but I didn’t think much of the idea. It sounded kind of silly to me. But you pulled the ideas together. I’m not familiar with Dr. Fuhrman’s particular teachings. I have just heard the name often and had no idea why he would say such a thing.
            Thanks. :-)

        • http://twitter.com/MacSmiley MacSmiley

          Dr Fuhrman is a colleague of Dr Greger. He is a board-certified family physician and author of several books, including Eat to Live, Eat for Health, and most recently, Super Immunity.

          His rationale for eating 3 large meals a day with no between meal snacks has more to do with breaking our great American constant-face-stuffing food addiction, the anabolic/catabolic digestion cycle, as well as recommending nuts/seeds/avocado be eaten WITH meals for greater nutrient absorption.

          What I meant to say is that this new information from Dr. Greger is just one more reason for me to stick to Dr Fuhrman’s commonsense Eat to Live recommendations.

      • http://twitter.com/MacSmiley MacSmiley

        Is it just me or is everyone else also getting a “Not Found” message when thr back up to watch older videos?

        I was able to view Priming the Proton Pump on the YouTube backup.

        http://youtu.be/4ivRY9YsdnY

      • Thea

        Thanks Dr. Greger for this explanation. It helps a lot to get rid of the confusion!

        • Michael Greger M.D.

          Now that So Should We Drink Beet Juice or Not? is posted I’m hoping that will help too! You can see why I had to make so many videos about it!

          • Thea

            re: “…that will help too! You can see why I had to make so many videos about it!”
            Yes, you really need the whole series to get an understanding. It is a complicated topic. (On the other hand, I cried fowl on the video that did nothing but ask whether or not bacon and veggies do the same thing. That video is only a question and no info! But I digress.)

            I’m fascinated by this stuff. And it is just one more important piece of information in that big picture of what it means to eat healthy.

            For what it is worth, here is some of my thoughts right now: I was thinking about the issue of “three hours later, best not to have fat in your tummy”. I tend to eat about every three hours or so throughout the day. So, perhaps I need to have my arugula salad as my last meal of the day?

            But if my nitrate/nitrite loading is at the end of the day, would I get any exercise-assistance benefits the next day? I’m not all that found of beets or arugula. So, I kind of want all the benefit I can get if I’m going to try to eat them. I’m not sure I remember the videos enough to say, but I’m guessing that I would miss out on the energy boost.

            So, then it would be matter of being thoughtful about when to have the arugula salad. Maybe I should have it in the morning (which would be very difficult for me since I’m now stuck on my yummy chocolate-banana oatmeal for breakfast) and just make sure that my mid-morning snacks and lunch are fat-free.

            Just thinking about things. It’s a lot to think about. I really appreciate the info.

        • Toxins

          Although indeed all foods contain fat, perhaps if you ate a low fat meal 3 hours after consumption of nitrates you would be better off. I tend to eat large meals and stay full for long periods of time. I do snack on fruits though through out the day.

          • Thea

            re: “I tend to eat large meals and stay full for long periods of time.”
            I’m more of an all-day grazer myself. Though I found that the oatmeal happily keeps me pretty full for quite a while most days.

      • MikkoL

        “…then hours later once the nitrates make it back into the mouth and produce nitrites, that’s when we should have no fat in our stomach.”

        How about the protective phytonutrients then? Aren’t they also gone hours later?

        • Toxins

          Do you recall that our stomach actively releases vitamin C to deal with this issue?

      • Marge9

        I’m not very good at timing when I eat fats vs.
        veggies.  And I wondered if there was
        much fat timing in all the prior studies out there where the higher intake of
        fruits and vegetables (traditional Mediterranean diet, DASH diet) were
        associated with healthy benefits. Having chronic health issues I am familiar
        with PubMed, the online source of studies, and so went there to see if I could
        find some additional information. It turns out that the lead author for the
        study cited in this video has since published two more studies.  

         

        One study indicates that the type of fat the nitrates
        encounter affects the outcome. Unsaturated
        fats actually act as scavengers of
        some nitrosating species.

         

        His other study found that different types of acids present
        in plants have different effects on
        nitrosation. As noted in the video, vitamin C promotes nitrosation. But ferulic
        acids (found in many plants) and caffeic acids (found in all plants) “markedly inhibited nitrosation”.

         

        The 2007 study by the lead author E. Combet analyzing the
        vitamin C and fat interaction was done “in vitro”—in the artificial environment
        of the test tube. E. Combet has followed up with two published studies in 2010.
        This is from the abstract of one of the studies: “Nitrosation has been studied
        in vitro in aqueous systems and less frequently in organic systems; however,
        there is a need to investigate acid-catalysed nitrosation in a system combining
        aqueous and lipid environments, hence providing a physiologically relevant
        model.” In some instances “unsaturated fatty acids acting as scavengers of
        nitrosating species, findings relevant to the nitrosative chemistry occurring
        in the stomach, where the gastric acid meets a range of dietary fats”.
        (“Development of an in vitro system combining aqueous and lipid phases as a
        tool to understand gastric nitrosation” PubMed ID: 20112267, http://www.ncbi.nlm.nih.gov/pubmed?term=20112267
        .)

         

        The other E. Combet study is at http://www.ncbi.nlm.nih.gov/pubmed?term=20026204
        PubMed ID 20026204.

         

        Does this make sense??? 
        Thank you Dr. Greger for your fascinating web site. I have
        just recently discovered it and find myself very busy taking lots of notes!

      • jb

        what if i have some beetroot juice, rocket leafs and a bit of cheese is this bad

  • Thea

    I’m confused now. The video talks about the problems of “fat”, not just animal fat. Yet, we have previous videos that talks about the importance of adding fat to salads in order for our bodies to absorb the nutrients from leafy greens. :

    http://nutritionfacts.org/videos/forego-fat-free-dressings/

    So, we want this cool process from our arugula and yet by adding the fat it could create the carcinogens? What am I not understanding?

    • Michael Greger M.D.

      Please see my response to MacSmiley above, Thea.

  • evanbrand

    Hi Dr Gregor,

    Can you cover glutathione?
    -If we should “take it”
    -In what form/foods to take it
    -what quantity to take it.

    Thanks,
    Evan

  • hcdr

    “…vegetables in the form of bacon”… i think that is the most hilarious nutritional quote since Homer Simpson stated “purple’s a fruit!”

  • http://twitter.com/MacSmiley MacSmiley

    Is it just me or is everyone else also getting a “Not Found” message when they try to back up to watch older videos?

    I was able to view Priming the Proton Pump on the YouTube backup.

    http://youtu.be/4ivRY9YsdnY

  • Marge9

    I’m not very good at timing when I eat fats vs. veggies. And I wondered if there was much fat timing in all the prior studies out there where the higher intake of fruits and vegetables (traditional Mediterranean diet, DASH diet) were associated with healthy benefits. Having chronic health issues I am familiar with PubMed, the online source of studies, and so went there to see if I could find some additional information. It turns out that the lead author for the study cited in this video has since published two more studies.

    One study indicates that the type of fat the nitrates encounter affects the outcome. Unsaturated fats actually act as scavengers of some nitrosating species.

    His other study found that different types of acids present in plants have different effects on nitrosation. As noted in the video, vitamin C promotes nitrosation. But ferulic acids (found in many plants) and caffeic acids (found in all plants) “markedly inhibited nitrosation”.

    The 2007 study by the lead author E. Combet analyzing the vitamin C and fat interaction was done “in vitro”—in the artificial environment of the test tube. E. Combet has followed up with two published studies in 2010. This is from the abstract of one of the studies: “Nitrosation has been studied in vitro in aqueous systems and less frequently in organic systems; however, there is a need to investigate acid-catalysed nitrosation in a system combining aqueous and lipid environments, hence providing a physiologically relevant model.” In some instances “unsaturated fatty acids acting as scavengers of nitrosating species, findings relevant to the nitrosative chemistry occurring in the stomach, where the gastric acid meets a range of dietary fats”. (“Development of an in vitro system combining aqueous and lipid phases as a tool to understand gastric nitrosation” PubMed ID: 20112267, http://www.ncbi.nlm.nih.gov/pubmed?term=20112267 .)

    The other E. Combet study is at http://www.ncbi.nlm.nih.gov/pubmed?term=20026204 PubMed ID 20026204.

    Thank you Dr. Greger for your fascinating web site. I have just recently discovered it and find myself very busy taking lots of notes!

  • Gary Gary

    what does the botton line means?

    【our body wasn;t designed to get its vegetables in the form of bacon】

  • David Colin

    I’m confused. If you are having an arugula salad or having grated beets on your salad, is it safe to have something containing fat such as avocados or walnuts at the same time?

    • David Colin

      Ok so I read the rest of the discussion, and I have to say, this whole concept seems totally counterintuitive to me. So eat some beefs or greens and they can either be great for your heart or carcinogenic, depending on whether you remember not to eat some nuts or avocados 3 hours later? There is something wrong here. I don’t believe “nature” would make nutrition this confusing – something you have to figure out via scientific analysis. Primitive people could never have known this.