Doctor's Note

This is the final installment of 3-part video series on sexual health. If you missed the first two, check out Survival of the Firmest: Erectile Dysfunction and Death and 50 Shades of Greens.

The watermelon effect via citrulline is documented in Watermelon as Treatment for Erectile Dysfunction and the jogging statistic, taken from the Harvard Nurses Health Study, can be found at What Women Should Eat to Live Longer.

The absence of weight gain is, surprisingly, par for the course when it comes to studies on nuts. See Nuts and Obesity: The Weight of Evidence. This may be for a number of reasons (see Solving the Mystery of the Missing Calories), including the "pistachio principle" (Testing the Pistachio Principle).

In addition to improving penile blood flow, nuts may also help prevent breast cancer (Tree Nuts or Peanuts for Breast Cancer Prevention?), inflammatory diseases (Fighting Inflammation in a Nut Shell), and sudden death (How Do Nuts Prevent Sudden Cardiac Death?).

I discuss the epidemic of adverse prescription drug side-effects in my 2012-13 annual review Uprooting the Leading Causes of Death and my new 2013-14 live presentation More Than an Apple a Day.

For more context, check out my associated blog post: Foods for a Long Life and Love Life, Pills vs. Diet for Erectile Dysfunction, and Pistachios May Help Erectile Dysfunction.

If you haven't yet, you can subscribe to my videos for free by clicking here.

To post comments or questions into our discussion board, first log into Disqus with your account or with one of the accepted social media logins. Click on Login to choose a login method. Click here for help.

  • brec

    Caldwell Esselstyn’s remarkable success with cardiac patients based on whole plants nutrition that is very low fat, and which explicitly excludes nuts, is causing me some cognitive dissonance just about now. Pistachios are about 2/3 fat by calories.

    • Veganrunner

      I am wondering if it isn’t because he is working with people with severe heart disease and is trying to reverse damage. I know this can be such a confusing issue. I often wonder the same.

    • HemoDynamic, M.D.

      Esselstyn’s cardiac patients (17 of them if I recall correctly) had severe coronary disease and 5 of them were given less than a year to live, so that was the reason he was so strict with them.
      People may disagree with me but for the general population (and most of my patients) they can eat nuts and seed without any problems, in fact only benefits.

      I do, however, have patients that have severe coronary disease two of which were given less than six months to live and weren’t candidates for any type of surgery (stents or bypass) which I did place on a very strict Esselstyn diet. Both are still alive, thriving and have had no cardiac events in 2 years. And secretly they have had some nuts and seeds! About a handful a week. I know it’s anecdotal but they ain’t dead yet! ;-)

      • brec

        These responses seem question-begging. If pistachios help ED by improving arterial function, why would having serious heart disease be a reason to avoid them?

        • Plantstrongdoc M.D.

          There is a difference between the penis and the heart. In flacid state the blodflow to the penis is very low; it does not function, but it “survives”, but the heart can not survive with severe restricted blodflow.

      • Plantstrongdoc M.D.

        For what it is worth, I agree. Severe coronary disease = Esselstyn diet (if you want to survive). For prevention = WFPD incl nuts and seeds. Anecdotes are the basis for new ideas – so they are always important.

        • brec

          What is the theoretical basis for the different dietary recommendation with respect to nuts and seeds between prevention and reversal/survival?

          • Plantstrongdoc M.D.

            As I see it (for what it is worth), if we are talking reversal (removing of fat deposits) of severe coronary disease, you have to avoid fat (in general) as much as possible. If we are talking about not building up deposits of fat in the arteries, WFPD is OK

          • I believe it is the fact that nuts/seeds contain saturated fats which are converted to cholesterol and omega 6/3 ratio. For Pistachio nuts the Omega 6/ Omega 3 ratio is about 5/1 (e.g. 16772 mg/ 332 mg) which is more then the recommended 6/3 ratio of less than 4/1. This ratio would tend toward more inflammation. Of course we don’t only eat pistachio’s so the rest of the diet would need to be factored in.

          • nuttyguy

            The omega 6/3 ratio is more like 50/1.

        • brec

          At this point I think I should say that I’m not trying to be a PITA; I have coronary atherosclerosis, am eating per Esselstyn, and have an intense interest in whether or not pistachios and/or other nuts would be healthful for me.

          I think my question hasn’t been answered: why would nuts and seeds, or more generally PUFAs in nut/seed “containers”, not contribute to creating lesions on the one hand, but interfere with their removal on the other?

          • HemoDynamic, M.D.

            I don’t know if there is a great answer for you yet but the analogy is if I want patients to lose weight the fastest then I put them on a very, very low-fat diet: No animal products and no added oils, and avocado’s, nuts and seeds only as occasional treats–meaning once a week and only a hand full. Why? The fat you eat is the fat you wear! And the fat you don’t eat is the fat you burn off your body–meaning weight loss!
            Same with your arteries. If you want to lose the fat (cholesterol) from your arteries the fastest way is to minimize the fat you put in your mouth. But occasional nuts and seeds don’t seem to cause a burden to you arteries that they start producing atherosclerosis. However, that said, I do not know if anyone has actually visualized the arteries forming fatty streaks while on a vegan diet with nuts and seeds vs no nuts and seeds.
            I hope this helps.

          • Joe

            There are factors which change as your body changes. For example, overweight people have a decreased ability to turn carotenoids into vitamin A – where as healthy people convert much better.

            Theoretically that might mean that an overweight person might have to use a non-vegan diet to get to a state of health where a vegan diet would be ideal.

            This is just my theory, but I am sure there are many factors which work like this – perhaps the nuts example is one?

          • Connie Sanchez, ND

            However, an overweight person would lose weight following a WFPB diet and that would help with conversion. Just make sure the diet is high in carotinoid-rich foods to insure sufficiency.

          • Joe

            I was just using this as an example to illustrate that the body’s function might change depending on what state it is in. Perhaps Esselstyn is right to leave pistachio nuts out of his diet, but for a prevention diet perhaps pistachios are a good addition.

            This wasn’t a comment on the effectiveness of a WFPB diet or about weight loss.

          • Thank you Joe, point taken.

    • BonnieK

      I am having the same confusion over this. My husband has suffered 2 heart attacks and is now trying to follow Esselstyn. At this point he has decided to not eat nuts. But this research really seems to point in the direction of nut consumpion…

  • WaltYz

    You have shown great personal restraint to stay away from all the possible nutty jokes in this video. Because this is such a hard-pressing matter, I won’t hold it against you.

    • LOL! WaltYz. Yes I have come to expect and anticipate Dr. Greger’s humor.

  • Liviu Deacu

    But pistachios do not even make it in the top 15 sources of arginine. What a pity that soy protein and pumpkin seeds weren’t studied. If the antioxidant protection of eNOS is more important, why not study amla or cellular antioxidants and erectile improvement?

    • Michel Voss

      Soy protein WAS studied: – Conclusion: Unusual LARGE quantities of soy isoflavones – due to their estrogenlike properties – INDUCE E.D. .

      • Toxins

        Soy protein isolates also increase IGF-1 concentrations, we should stay away from the stuff in general.

        • Michel Voss

          … “up to three servings did not increase IGF-1.”…

          • Toxins

            Soy protein isolates and soy protein are completely different substances, one is an extract, the other is a whole food.

            40 grams of soy protein isolate will increase GF-1 concentrations significantly and is far more potent than the milk based protein in increasing IGF-1, as IGF-1 concentrations are nearly doubled when 40 grams of soy protein isolate is compared with 40 grams of milk based protein.

            “When comparisons were made for women within the HRT (hormone therapy) and no-HRT groups, baseline values did not differ for the SP and MBP treatments. Similar to the overall findings, serum IGF-I levels were increased by both protein supplements; however, soy protein had a more pronounced effect in increasing serum IGF-I levels in women who were not on HRT”



          • Michel Voss

            Tofu is made by coagulation of soy milk from WHOLE soybeans. It is not only a soy protein isolate. Are there people who eat pure soy protein extract?

          • Toxins

            I apologize, there is some confusion. When I commented originally on your post I assumed you were talking about supplemental soy protein. You can find this commonly in energy bars, in protein supplements, and mock meats. Tofu alone is not soy protein isolate, as you stated, and cannot be viewed the same, as you also stated.

  • Though eating pistachios have their benefits I stay away from eating them, and instead I eat lot of almonds and walnuts, and I eat a plant based diet. I am a believer and I have benefited from keeping my pH at an alkaline level of 7.4-5. I found that when I ate a lot of pistachios it dropped my pH level.

  • I eat only whole-food plant-based food, including daily a couple of tablespoons of peanuts, almonds, and walnuts and a smoothie mostly of green leaves I pick from vegetables like broccoli and kale and weeds. Erectile dysfunction went away in about 3 months, with this diet.

  • fannybrobb

    But what is “significant improvement”? can someone tell me how many percentage of people got better from the pistachio diet?

  • Nelson

    In any case eating a WPBD (whole plant based diet) is he key to ED and anyone who follows Dr. G’s daily video and blogs is well aware of this. We are ‘meat leavers’ on this site and as before leaving meat, recall how mich animal product we used to consume so it still rings true that too much of anything is no good.

  • rojo

    So, wondering if it matters how the pistachios are processed (roasted, raw, etc).

  • Killerbees

    The problem with consuming nuts of any kind is a problem for many of us specifically because of the arginine content. Cold sores and other herpes related problems are exacerbated by increased arginine intake.

  • DvoraChesed

    What about men supplementing with arginine capsules? Recommended?

  • Madhava Das

    Clearing Up Nut Confusion

    A low-fat, whole-food, strictly
    plant-sourced diet = simultaneous calorie minimization (aka calorie
    restriction), and volume maximization = optimal health without hunger.

    We know that calorie minimization with high nutrients, i.e.
    calorie restriction, is the only intervention to increase both average and
    maximum healthy, cognizant lifespan.

    From Dr. Esselstyn and from others including Drs. Castelli,
    Roberts & Campbell we know the key markers for cardiovascular health are
    sufficiently low total and/or LDL cholesterol numbers.

    As explained in my book, Eat Your Way To Health: Healing,
    Kindness And The Plant Life Cycle (which received a 5 star book review from
    Maynard Clark, Research Administrator at the Harvard School of Public Health)
    successful calorie restriction is a matter of achieving and maintaining those
    low numbers (150 and 80 respectively or possibly a little lower than that).

    Nutrient to calorie ratio (nutrient density) follows the
    plant’s reproductive life cycle. The
    early appearing plant parts like leaves, stems and buds (broccoli) have the
    highest ratio, while seeds and nuts have the comparative lowest ratio (the
    later a plant part develops the more time the plant has had to increase it’s
    calorie storage potency).

    We are mostly the same, but with some differences. Yes, nuts have nutrients, but they also have
    lots of calories. So the test is can YOU keep your cholesterol numbers low
    enough while eating nuts or not? Some
    can and some can’t. It’s a simple
    matter of a blood test.

    If your numbers are below the threshold while eating
    nuts, great – if not don’t eat nuts.
    This is the complete nut confusion solution – no more cognitive dissonance.

    • Dennis Franco

      All I can find are roasted pistachios in any store. The video didn’t mention whether the pistachios were raw or roasted in the study. Please help.
      Denny in Sarasota

  • Ronald Chavin

    Unfortunately, pistachios, peanuts, and Brazil nuts are the 3 nuts with the highest risk of containing cancer-causing mycotoxins:

    • Toxins

      Mycotoxins occur, and exert their toxic effects, in extremely small
      quantities in foodstuffs. Their identification and quantitative
      assessment thus generally require sophisticated sampling, sample
      preparation, extraction, and analytical techniques.

      Under practical storage conditions, the aim should be to monitor for the occurrence of fungi. If fungi cannot be detected then there is unlikely to be any mycotoxin contamination.

      • whew! I’ve never heard of mycotoxins before so what does this mean bottom line for how I store these three nuts in particular ? : the fridge or the cupboard ?

    • Bobloblaw67

      Brazil nuts have anti cancer selenium

  • brian

    no offense, but a better voice for the voice-over would be appreciated

    • Thea

      Dr. Greger donates his own time and voice for these videos. I appreciate that he takes the time to do this work. And I and others love his voice. You are entitled to your opinion on this topic, but it is not necessary to voice it. “No offense, but” that kind of criticism is petty and unnecessarily hurtful. (I’m sure Dr. Greger has a thick skin by now. But still, take a moment to practice basic manners brian.)

      • brian

        maybe i care more about the success of the site, which i think is good and important, than i do hurting someone’s feelings who has probably heard this before (judging by your ‘thick skin by now’ comment.)
        thanks for patronizing me though, excellent manners!
        i’m sorry if his self-esteem rests entirely on his thinking he has a voice-over quality voice.

        • Toxins

          I have never had any problems with Dr. Greger’s voice holding me back from understanding fully what is being discussed on these videos. I have to agree with Thea, Dr. Greger works hard to bring this information to light, we need to be grateful that someone like him can spend hours (along with his crew of interns) scouring the latest studies for the latest in nutrition research. Very very few people can do this, and even better, present it in easy to understand videos with the studies attached below, for free! Just to enlighten and educate.

          • brian

            i’m not debating anything that you’re talking about except the voice. just because it doesn’t distract you doesn’t mean it doesn’t distract others. how will we even know if it is a distraction to others if people who politely comment on it are responded to as such.

          • VegAtHeart

            Another option is to use the feedback section of this website.

          • mommkat

            Personally I love Dr. Greger and his voice. He projects the necessary convincing sincerity to give credence to his information.

          • SethF1968

            For God’s sake B rian stop being a prima donna!!. Be grateful that Dr Greger took the time to give you this information.
            I think he does an excellent job as a narrator–but if he didn’t I would not care.Take a Valium, have a drink. smoke a joint or go into psychoanalysis for 30 years!!

          • weedeater39

            Excellent reply Seth.

      • VegAtHeart

        Good point Thea. Yes, Dr. Greger is extremely generous and also an internationally respected professional speaker. We are very lucky indeed to have this nutrition resource!!

        • Toxins

          Speaking of lectures, I have yet to meet Dr. Greger in person. I currently live in Houston, ill have to make a drive up to Marshall, TX this coming January.

          • VegAtHeart

            I have met him in person. It is worth the drive!

          • Toxins

            Austin has Houston beat in that area, and many other areas too. I currently attend the University of Houston and am excitedly anticipating my graduation so that I can leave this city. The only whole foods plant based restaurants I can eat at are Genghis Grill, which I have only done once, and and whole foods market.

          • VegAtHeart

            Oh that’s too bad that there are too few WFPB restaurant choices in Houston. That’s one good incentive for you to venture off.
            Given the passion for nutrition that you exude, I guess you must be majoring in something related at Uni? If so, you may some day offer the NutritionFacts community some of your own breakthrough discoveries.

    • Veganrunner

      Brian what does your comment have to do with the information presented? Odd.

      But I did catch Dr Greger giving a wonderful lecture in my hometown. Great speaker. He knows his stuff.

      • brian

        the information presented came in the form of his VOICE. sorry you don’t understand that.

  • A

    I subscribed but cannot view any videos.

  • Bob Grant MD

    total and utter nonsense.. absolute distortion with misleading thoughts and comments …another MD trying to sound smart and contemporary about serious medical issues they know little or anything about. More hype than substance. People need to eat an Organic plant based diet, exercise regularly, cardio and muscle building, respond w “cool” to stress i.e. less stress, desire pleasure and feel the benefits of lubricants and oils…and love sex…Please stop all the BS Greger, it will destroy your credibility..

    • Toxins

      Dr. Greger supports an organic, plant based diet with regular exercise. There is no disconnect with this message. He is merely sharing an interesting study that was recently published showing potential benefits of pistachio consumption which adds to the bigger message showing the power of plant based diet.

  • Fan O McDougall

    Thanks for the video, Dr. Gregor!

    I have been following a strict Vegan WFPB diet for 19 months–pretty much starch-based McDougall style. I also include copious amounts of the best veggies and some fruit. After remarkable success with my weight (83lbs lost) and health, ED problems still persist despite improvement.

    So I am giving this pistachio thing a try. I am unclear as to whether 100 grams of pistachios should be measured with or without the shell??

    I must admit to being a little concerned about the added fat and calories…I’m hoping that if that works, a reduced consumption might be sufficient for long term benefits.

    • Thea

      Fan: I’m a fan O you! :-) That’s a great story, though I’m sorry to hear that your ED problems are not fixed as well. I think its great that you are doing all that you can to help yourself. And now you are going to take another step.

      I can’t answer you question in regards to the grams, but it may help put your mind at ease a bit on the issue of calories. Dr. Greger has a video (which I don’t have at my fingertips, but hopefully won’t be too hard to find), which shows how some people actually loose weight eating nuts. There are no guarantees. (I know other WFPB people who say that they had to give up nuts in order to loose weight.) But it seems worth a shot.

      Best of luck to you and I hope that someone can answer your question and that you will report back to us how it goes.

    • Ace Pex

      I have the same question… was the 100 grams of pistachios used in this study measured with or without the shell??

  • healthwriterJan

    1. To my knowledge, only one study about pistachios effect on erectile dysfunction is in Pubmed. Placebo effect and psychological effects during testing is possible.

    2. In several other studies pistachio consumption was associated with low blood cholesterol levels, but not one single study (to my knowledge) has confirmed an actual effect of pistachios on atherosclerosis, heart disease or mortality from heart disease.

    3. Pistachios are often contaminated with Aspergillus flavus, which produces aflatoxin. Aflatoxin can induce liver cancer. No association between pistachios consumption and liver cancer was established so far, though.

    To answer some comments:

    Roasted pistachios have about 60% lower antioxidant activity than fresh (raw) ones. But the direct beneficial effect of any antioxidant on heart or other disease has not been proven so far, as I know. If it was, I would appreciate a link.

    One possible nutrient in pistachios that could improve erection is arginine. No effect of various lysine/arginine levels on vascular reactivity was found in this study:

    I made a research about possible health benefits of pistachios with references to all of my above claims here:

  • Emily Newman

    Great point at the end Dr. G, why rely on a pill to “get it up” when instead you could just change your life style and be able to perform when the time is right without having to worry about taking a pill.

  • Charlie Behrens

    I don’t see whether this study was done with California or Turkish pistachios. Does anyone know if that makes a difference?

  • Tuba

    So, this site is really just a front for anti-fat vegetarianism. The last vegetarian expo I went to I was the skinniest person there. I was a low-carb meat-eating reed amongst hippos all extolling the virtues of rice, pasta, bread and potatoes…. Vegetarians thy name is in denial obesity. The bug-a-boo is not saturated fat or cholesterol per se but a diet high in simple carbs. Cholesterol is just the cop who shows up at the scene of the inflationary high-carb crime. Ditch the simple carbs, no cholesterol cops, better arteries, better bedroom. Your message isn’t a bad one if you get off your plant high horse and the lipid hypothesis rant. You also might want to now and then consider having a graphic of a male penis that is not mutilated. Circumcision is sexual assault and should be prosecuted. It’s a mistake that lasts a lifetime. And in my lifetime the vast majority of wars and violence has been caused by damaged men.

  • Alex

    Love to see these discussions steering away from “mainstream” medication to a more natural approach.

    After a long period of junk food and low exercise coupled with alcohol fueled nights, I found myself having erections issues at only 25!
    It was the trigger that got me back to dieting, daily cardio for at least an hour. I must admit I did try a few mainstream and alternative solutions but whatever it was worked. I’m inclined to believe it was the physical activity.
    Still occasionally have issues but I believe those are just self induced. I have a very nice diet now with veggies, nuts and seeds and lot of raw stuff.

    By the way any thoughts on stuff like Hogweed tincture? like this stuff Is it something people have tried?


  • Really liked this blog.

    Buy Generic Viagra

  • Wellness Man

    Thanks for the pistachio info and health comments!

    I don’t have anything against wholesome plants. Who does?

    But here’s a comment on plants from a historical point of view. In the colder months, if they hadn’t stored sufficient quantities of preserved food, where did history’s people in New York, Paris, and Newfoundland get sufficient plant calories before the advent of steamships, jet planes, and heated greenhouses? Freshly butchered animals and fish and whatever might have been put up as preserves (or smoked) were what people made feasts of in the colder months. Meat and fish were sustenance. Salads don’t cut the mustard in the cold. Bean after-burn might clear out the igloo and perhaps cause flatulence combustion. Historically and currently, Alaska is not known for its nut trees.

    Fresh game was often the lifeblood of hunter-gatherers. In the non growing season, the same was true for the farmers. Game or stock animals or animal products like eggs and milk were customarily part of the diet. Even the poor farmers during the Great Famines (aka Irish Potato Famines) poured milk on their cooked potatoes. Do you know how many potatoes a family of four consumed per day during the heydays of the Irish Lumper potato diet in Ireland? One source says approximately 120 potatoes was a number that sustained such a family. Potatoes have a full compliment of amino acids and the milk provided further nourishment. No one would recommend that as a balanced diet but the population quadrupled — and overpopulated the land — using that diet.

    If you look at animal meat studies of the last 50 years, how many were conducted using good quality, grass fed or otherwise “naturally’ raised animal meat? I willing to hear more on such studies. Show me some studies who use healthful, healthy, and physically active subjects (not competition athletes who may abuse their bodies). A number of the comments in this section of posts discuss diets for unwell people. I’d like to see more on diets for people who are well. People who:
    1. do vigorous and balanced fitness
    2. are in good shape
    3. get downtime (naps and resting)
    4. get regular intimacy
    5. work a non-abusive job
    6. have regular and practical ways to reduce or release stress

    And in general are happy and healthy. How about a diet for people who are thriving or at least are on a happy, balanced, and workable daily routine?

    Let’s see some comments that lead with “My wife is fine and active. Here’s what she eats. I am fine and fit. Here’s how I purchase, grow, and prepare my food.”

    I’ve done plant-based diets and a few other test runs at various diets. The strategy that works the best these days in my 50s is listening to the body. Food combining charts and Ayurveda dosha recommendations also help guide me. There are days and weeks where I eat once or twice per day. Other times my system calls for more frequent meals. There are days where my body calls for more protein (sometimes this might include red meat and sausages), and days where it calls for more salads and greens. On the average, I eat some meat and lots of vegetables and some fruit every day. I also fast periodically depending on health markers like digestion, energy levels, and focus. I also factor in the time since last fast.

    If this sounds a bit excessive or dull, let me add this — I love deserts! I make good deserts and I buy the best deserts I can affordably and easily access.

    The hunter-gatherers fasted by default, because, depending on the time period and other factors, food was sometimes or frequently scarce. They had to be fat-adapted. How many modernites are fat-adapted? I’m an ectomorph who once had a stint with issues of hypoglycemia. Happily, now, because of being fat-adapted, I rarely have an issue with blood sugar.

    Let me know what you think. I live with wellness as a priority and strive to have an open mind, adapting to the new information and what my intuition and body are telling me. A site I run is SedentaryNation.



  • saying that eating pistachios “significantly” increased this and that is very vague. And I can’t understand the numbers in the study’s report so what kind of “improvements” were there? Were the men able to maintain an erection for 2 minutes and that was significant?


    I can’t seem to find a copy of this Mediterian diet without dishing out money. Can some one help me with this?

  • Francis Levira

    It is important to be fare and less bias in presenting every findings. This study reported statistically significant decline in testosterone level in pistachio group. Dr Greger and authors conclude no side effects. Is decline in testosterone caused by phytosterol in nuts not a negative side effect? Also some reported changes were very small example Right and Left RI changed from 0.8 to 0.9.