Doctor's Note

Why is high dietary intake of saturated fat associated with reduced semen quality? What’s the connection? Sex steroid hormones in meat, eggs, and dairy may help explain the link between saturated fat intake and declining sperm counts. That’s the subject of my next video, Dairy Estrogen and Male Fertility.

More on male infertility in my videos Fukushima and Radioactivity in Seafood and Male Fertility and Diet.

Diet also has a role to play in sexual dysfunction:

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  • Serious About Health

    Sperm Quality and Motility seem to be, like ED, “the canary in the coal mine.” If there are problems there, there are problems everywhere! So many key issues/aspects such as this/for which most people know way to little. We are so proud and so competitive in some aspects, but in some very key aspects “we” are mostly clueless which is unfortunate. Thank YOU for helping to alleviate that. If only those who need the information the most are aware of this site Keep up the great work in all regards!!!!

  • Merio

    I’m studying embriology during this days and there are really a lot of factors that could be deleterious to our sexual functions (eg smoke).

    • tbatts666

      Smoking screws everything up. Good point!

      • Merio

        Yes, it is really a nasty substance.

      • Marie

        I can’t agree strongly enough. Thank god I was able to quit while still young in my late twenties thanks toy then family Dr who scared the c**p out of me with his warnings about the pill and smoking and my increased bronchitis. Now mid forties I’m sooo glad I quit when I did. A GF’s mom quit but sadly found out she had cancer months after. Hard to judge. My heart broke for her and for what it’s worth my GF mom was one of the few who took ownership of her choice to not quit earlier but just like my dad we put it aside and took care of her. Others quit because of both so there’s that. Ironically like many others Ive developed an allergic like rxn to cigarets (even just the smell on clothes, etc). My sister calls them ‘cancer sticks’ but I don’t think the term really takes in all the damage they do.

  • Gabe

    Nature always has the final say when it comes to its own survival. I sense that human population is in play here. Just looking at the bigger picture.

  • ken

    How about GMO’s. Any research about that poison in our food
    and sperm count?

    • largelytrue

      Dunno, but we could flip the question around to get some context to start with. You are concluding that it’s “poison” based on what research?

      • Joe
        • largelytrue

          I looked at the link and pulled the third study cited at the page to start the investigation. After a bit of a runaround from site to site I eventually got to the full document, which is apparently published by the Journal of American Science, which shows no indication of being a peer-reviewed journal. Actually the info suggests that the journal is a bit of a publishing mill: “ aims to provide science community the best services in publishing scientific research findings, and providing the latest science news, jobs, and other information. We strive to provide the best service to the public, scientists, industries,and academic institutions. We plan to provides services to allow readers to subscribe and access to a large number of science journals.”

          The idea that they are trying to give a superficial impression of authority and peer-review is especially telling when you consider how similar the name is to the American Journal of Science, which is presently the number one peer-reviewed journal in geoscience, has long been linked with Yale, and has a fairly high impact factor. Also, having “America” in the journal name may be appealing to foreigners trying to make a career in research. Note also that on the website of the peer-reviewed journal they are very clear that there will be a review process, and give a strong impression that they don’t just publish anything, that they actually know something about the area in which they publish:

          Have you actually looked closely at these sources that in the link that you showed us? Do you know the other citations to be much higher in quality, and if so, why didn’t you tell me about the poor quality of this one?

          • Joe

            I was making the point that no human research exists – only animal studies. If The Journal of American Science is publishing hearsay to look like peer reviewed studies, then that is a separate – but extremely important issue. Certainly with politically charged topics such as this we are seeing the perversion of science from all angles.

            I’m sorry if you thought I was trying to blind you with pop science. That wasn’t my intention. From a research point of view we can garner precious little from animal studies in terms of long term human effects. In response to your original point – the question of whether or not GM food should be considered a poison depends on your point of view. Personally, I think all new cars should be tested before being allwed on the roads, and I think the same applies to our food. The obvious contention here is ‘new’ – while the FDA have already judged GM crops to be ‘not substantially different’.

          • largelytrue

            Right, so you’re saying that animal studies showing harm exist as part of that point. With that, would it not be a huge omission to not point out that the animal studies to which you are referring are not peer reviewed, and hence not meeting important criteria for legitimacy?

          • Joe

            So you’re calling into question one study (out of a handful) that may or may not be peer reviewed. You have made several assumptions to make the case that it is not peer reviewed, however we still do not know either way. I judged the study to be of value – and if you have found evidence otherwise then I am happy to hear it. At least I was, until you insinuated that I was fully aware of this possible subversion and therefore complicit in its circulation.

            Now you’re painting it as if the whole argument hinges on this one study; an argument which I myself do not give so much weight to anyway, given the use of ‘only’ in the original post. You are right to question the study – but please do so within the context that it appeared and without presenting your assumptions as fact. I checked each link, and judged the article to be of value to the conversation – however I am well aware that it would be impossible for me – or any other commenter – to validate 100% every study that popped up on our computer screens. Yes – this is what the peer review process is for – but that puts enormous pressure on the integrity of that process, which can and does lead to dishonesty on the part of the Journals. If you feel that the Journal of American Science is gathering unreviewed studies and presenting them as peer reviewed, the correct course of action would be to find hard evidence and take it up with them. By all means let people know (and I am please you made me aware of this) but please recognise that your assumptions about my intentions and about the validity of this study remain as such.

            There was also a video linked in that article which was definitely not peer reviewed – nonetheless interesting and valuable to this discussion. I never specified the peer reviewed nature of the material posted. It was you that created that criteria, and then judged me against it.

          • largelytrue

            I was talking about the Journal of American Science to add support beyond reasonable doubt that the one article was not peer reviewed. I could probably find other primary research in that link that has not been peer reviewed, but you can see that it has already taken me considerable time to make my case for just one of them, and even with that investment I’m meeting with heavy resistance. Not being peer-reviewed is a very very bad thing for something posturing as primary research to be.

            Of course some material that is not peer reviewed is worth discussing from a scientific point of view, but it’s usually stuff that tries to invoke and discuss many lines of primary research.

            I’m challenging YOU for linking to a site containing citations of primary research in rats and pigs and apparently not doing any fact checking at all, neither of the site, which looks to me to be more charged by politics than science, nor the articles that the site cites, at least one of which is clearly not peer reviewed. This is a blow to their scientific integrity and a blow to yours, because in this scenario, you do have some responsibility to point out that the research has not passed peer review of any kind whatsoever if you still want us to consider it. And usually we do ignore rat studies of this type that are not peer reviewed (most scientists do, at any rate), so asking people to consider it at all looks a bit like special pleading for a favored hypothesis.

            I didn’t “create” the idea that primary research should be peer reviewed, either. It’s a general heuristic. The more technical and specialized the material being publicized (as in a study of emerging disease in the cells of rats that have been exposed to various experimental diets…) the more you want other people doing that kind of research to be able to attest that the methods used were reasonably sound in that particular case.

    • Gar Zuzik

      (said in a friendly tone)
      Based on my experience when questions like these are asked it shifts the conversations to conspiracy theory driven. In my opinion we simply cannot even take a clue at the consequences of gmo (even though there are numerous methods ex. matt lalonde I believe discusses this). Top researchers would need to be interviewed before speculation and fear conjuring and spreading misinformation.

      In the mean time it would be wise to look at much more proven and simple ways to improves one’s health (whole food plant based). Of course in a free-market anyone can go buy non-gmo products, but as a 23y.o. college student I will let others stimulate the economy $$ while I focus on getting in foods people should be eating but aren’t lol.

  • Thea

    This reminds me of a story in one of the bonus sections at the end of the Forks Over Knives DVD. They were interviewing some type of doctor (I don’t remember what type) who at least in part counsels women who want to get pregnant. If memory serves, the doctor was mostly talking about the women and how converting to a whole food plant based diet solved most of the fertility problems she saw. But my guess is that the men were eating the same food. (Maybe the video said that too. I just don’t remember.)

    Here’s my point: Based on what this NutritionFacts video says, I wonder if improved fertility for whole plant food based couples is actually due more to the improved diet of the men leading to better sperm rather than the direct effect on the women. Interesting thought! My real guess it that it’s probably very helpful for women’s fertility too – we just don’t have specific studies or NutritionFacts videos on that yet. :-) (As far as I remember.)

    • guest

      Its probably both, but I do think you are right that a good part of what we thought was on the woman’s side was in actuality on the man’s. Since most men I know have a hard time keeping f/v down this doesn’t surprise me at all.

    • My naturopathic practice is 100% fertility. In the last two years since recommending a whole foods, plant based diet to patients, I’ve seen much higher success rates. Many of the couples I work with are integrating my advice with their medical fertility treatment. The couples where both the male and female are following a plant based diet at least 5 days per week are seeing the greatest benefit. I would love to see research conducted on this. The medical fertility clinics aren’t going to promote this way of eating unless there are human trials.

      • Thea

        Judith Fiore: Thank you so much for sharing your story! It is so cool to hear that confirmed by someone who sees patients. I agree with you: It would be really nice to have some solid research on the topic. In the mean time, at least there are people like you who are helping out with the best information you have. Sounds like you are making a big difference in people’s lives.

      • Gar Zuzik

        It would be interesting to converse about this with you because it seems from my perspective that anyone even close to my age of 23 simply doesn’t care about fertility. The benefits of instant gratification trumps all (my opinion about the desire to conform and also the addictive properties of foods), as evidence by health markers in the usa.

  • Is the saturated fat talked about here being bad for sperm saturated fat from animals or plants? I am quite sure the saturated at being spoken about here is form animals and that should be clearly stated.

    • Han

      If you can find that being specifically described in these studies you have a point.

      • It is not addressed specifically but it appears to be alluded to. Dr. Greger presented evidence that walnut improved sperm vitality and shape and walnuts contain saturated fat. They also contain omega-3 and other nutrients that can be the reason for the support of sperm cells.

        • largelytrue

          Walnuts have saturated fat because they have fat. Pretty much all fat in plants is something of a mix, but in the case of walnuts the balance is overwhelmingly toward unsaturated fats, polyunsaturated especially:

          That is, if I were looking for a way to get a lot more saturated fat from whole plant sources, walnuts would not be at the top of my list.

          • Yes I understand walnuts have a mixture of fat leaning towards unsaturated and polyunsat fats. The point of this video is saturated fats have a negative association with sperm vitality. Walnuts have saturated fats also yet the help sperm to be strong. The question is does the saturated fat not have a negative effect on sperm strength because plant saturated fat has a different effect on sperm than does animal fat, or is it that the omega3 and of nutrients of walnuts cancels out the negative effect of walnuts saturated fat. I personally feel the animal saturated fat is the culprit and the plant saturated fat, at least in good fats of walnut, and coconut oil, almonds.

          • largelytrue

            There is different packaging, of course, and an association with saturated fat is just that, an association. There can be mitigating factors and there can be confounding factors, but still you are citing how you “feel” on the matter and use walnuts as an example of your feelings about saturated fat when really they don’t fit too well as an exception to the “saturated fat is bad for sperm” hypothesis that distinguishes between animal and plant sources of saturated fats. If the amount of saturated fat in a plant food is relatively small, then other effects will of course dominate.

            I’m not necessarily saying that I believe saturated fat is the main mechanism at work behind this association; I’m just challenging your reasoning, because it seems a bit like you may be shaping your reasoning according to what you want to believe.

          • I am shaping my opinion based on how the saturated fat i largely eat, walnuts, almonds, coconut oil effect my health and my sperm. My plant based diet is very specific and it has removed illness from my body. When I ate meat that was a different story. Now if saturated fat is the problem I would like to know what were the sources of saturated fat that were associated with sperm weakness because the saturated fat I eat makes my sperm strong, if it is saturated fat that does actually have a cause and effect on sperm strength, but my own body I would have to say that animal fat is the problem.

          • largelytrue

            How do you determine the effect of the coconut oil on your health and sperm?

          • I determine that through tests results from my dr.

          • largelytrue

            And the tests implicate coconut oil as the cause of favorable outcomes how?

          • No. Before my conversion to a plant based diet based on purely alkaline, non gmo, an d non hybrid foods, my health has greatly improved. I haven’t been sick and I haven’t had any medical issues since I adopted a plant based diet. I eat highly saturated plant based foods but not gmo or hybrid foods containing saturated fats. I eat a lot of walnuts, almond, and coconut, and much more than what people generalize to be good. I posed the initial question because the source of fat that was associated with weak sperm wasn’t given. Because of my personal experience I am curious as to the sources of fat that was associated because even with my heavy use of plant based saturated fat my health and conditioning are lovely. Now I understand that only an association was given, and I would still like to know what the sources of fat were. If there is a cause and effect relationship I want to know what and if the differences between animal based fat and plant based fat are on sperm health. If there is a cause and effect relationship, and my heavy use of these saturated fats still have wonderful outcomes on my health the that wold support that the problem is with animal fat and not plant based fat in the case of walnuts, almonds, and coconut oil, and coconut meat, yummy!

          • largelytrue

            The better should not be confused for the best, though. It’s great that you feel better, but it doesn’t mean that eating lots of coconut oil was an intelligent facet of your multi-faceted change. People feel better adopting a Paleo diet all the time, but it’s not because eating lots of meat is good for you over the long term; it’s often because the prior diet was so bad.

            Here’s an example of Greger’s position on coconut oil: Note that atherosclerosis is a risk whose outcomes are primarily seen over the long term, but is still very very important to consider if you want to eat healthily. Similarly, it’s also worth considering that the whole nuts do have components within them that probably help to blunt the impact of the saturated fat within. For one, the effects on the lipid profile seem partially driven by the ratio of saturated to unsaturated fat, rather than the absolute amount of saturated fat. For another, the fiber and antioxidants in the packaging may help somewhat. Coconut oil is highly refined, and highly saturated, so it doesn’t share these same mitigating factors. I consider it to mostly be a consumer fad supported by weak thinking and strong marketing.

          • Oh my gosh are you reading what I wrote or you just trying to prove a POINT? READ the first “Is the saturated fat talked about here being bad for sperm saturated fat from animals or plants?” I don’t know if the saturated fat being spoken about IS all saturated fat are not, which is the reason I asked the question? I ASKED the question because I would like to know. I eat a lot of plant based saturated fat without any issues and MY HEALTH IS AWESOME! IF, please SEE that I wrote IF, IF the saturated fat in the study is more than an association and has a causal affect I WONDER what the sources the FAT in THE study are. The point being made in the video is that there is an association between saturated and sperm weakness. I cut out all my saturated animal fat consumption and yet I consume a lot of saturated plant based fat and have greatly improved my health, energy, and stamina. IT COULD BE THAT THOUGH FAT IS ASSOCIATED WITH WEAK SPERM, BUT IT NOT A CAUSE OF WEAK SPERM.
            THE POINT HERE GOES BACK TO THE FIRST QUESTION “Is the saturated fat talked about here being bad for sperm saturated fat from animals or plants?” That is what I want to know. I already understand all the points you made, but none of them answer my question. If you can answer this very specific question then I welcome your answer, but if not you are giving me answers to questions I have not asked.

          • largelytrue

            Your reasoning tends to embed the answer to your own question, so forgive me if I tried to challenge your assumptions:

            “I personally feel the animal saturated fat is the culprit and the plant saturated fat, at least in good fats of walnut, and coconut oil, almonds [is not]”

            It was at this point that I started to feel that you were begging the question. That is, you assume that coconut oil is a ‘good fat’, so how could it be bad? And you eat plant based saturated fat “without any issues” so how could its impact on male fertility be bad? You evidently have tests that ‘prove’ it to your satisfaction. When you say:

            “I am shaping my opinion based on how the saturated fat i largely eat, walnuts, almonds, coconut oil effect my health and my sperm.”

            It implies that you have determined cause and effect in a very detailed way in your personal case, which is a very bold claim to make.

            The article that you are asking about is freely available. I opened it up and it looks like they base saturated fat estimates by interpreting Food Frequency Questionnaire data. Their estimate of saturated fat is just that: an estimate of total saturated fat consumption from animal sources. They did not try to track how much of the saturated fat came from plants and how much came from animals, any more than they tried to estimate the amount from cheese and the amount from meat. These are Danish soldiers, though, so I imagine much of their plant saturated fat was from chocolate and cooking fat and similar stuff. Substituting cooking fat from plants for cooking fat from animals will tend to reduce the total amount of saturated fat consumed, though, unless it’s imported coconut/palm oil, so total plant fat probably attenuates the association in this case. Writ simply, the study was not well set up to answer your question. Greger said that his next video tries to unpack the saturated fat association in this case, so he may be able to present a pl

          • Gar Zuzik

            If i may add the idea that food is a package deal as well.
            A ton of other things in almonds/ect sources of saturated fats other than just that fat or %/amount of a type of fat.
            (they couldn’t put a nutrition label on an almond bag of all the plant drugs/chemicals probably. (size 1 font) :)

            Those other component (even some in oil forms) could make all the difference.

            Are those components preventing oxidation/rancidity and ultimately damage in the body and prevention of healing?

          • Gar Zuzik

            Let us forget about the anti-oxidants/plant chemicals/drugs within whole food plants that could make the difference between saturated fats of animal or plant origin.

            (recommend the confusing journey of understanding dr. ray peat endocrinologist. He mentions how horrible polyunsaturated fats can be within the body, but in a whole food plant based form it can be completely opposite).

  • pbdoc

    okay, what about this bizarre finding:
    People who eat less meat and more veggies have reduced sperm count? I couldn’t find the actual study last week, but would love to hear Dr. G’s/NF team’s thoughts on it.

    • Bernard

      Vegans and vegetarians aren’t in the infertile range, but they believe the lower numbers are due to either nutrient deficiencies (because many vegans don’t realize they should supplement b12) or chemical residue in foods.

      • pbdoc

        Thanks for the actual study link Bernard, and your comments. I did notice they had a much smaller # of veg ppl as well.

      • pbdoc

        I remember reading of the chemical residue/pesticide hypothesis… but wouldn’t that mean the omnivores would have more exposure to those since they bioaccumulate in animal tissue? And therefore.. have lower sperm count? I’d say it was more related to B12 perhaps..

    • Thea

      pbdoc: I recommend taking a look at more of the videos and articles on this site about sperm count. I can’t remember which particular video it was, but there is one video that talks about vegans (or men eating a certain plant food?) having lower sperm count only in the sense of percentage per volume of ejaculate. What they found was that the total/absolute count was actually the same. The difference is that the vegans/vegetarians/plant eaters simply had a larger volume of ejaculate. I don’t know anything about the article you are talking about, but maybe they didn’t take the bigger picture into account in their counting?

      Hopefully someone will be able to comment on the actual study for you.

      • pbdoc

        Yeah I’ve seen that vid, think it was in relation to soy consumption. Thanks

      • tbatts666

        Concentration vs absolute number. Right on.

    • Also, the vegetarian group were lacto-ovo vegetarians. This could demonstrate that dairy and egg consumption can affect sperm count. I would like to see a study comparing 100% plant based or vegan males with omnivore males.

    • DarylT

      Two things, first, as stated by someone in the posts on that site “it is interesting to note that all participants
      were actually patients to the hospital’s infertility clinic” in other words they aren’t necessarily representation of the broader population, you’d expect them to have lower counts. Second, as stated by Dr Gregor in another video, Vegans have been found to have higher overall volume for the same number of sperm, this means the lower sperm count is misleading as to what is going on.

  • Tobias Brown

    Are chicory-based coffee substitutes healthy? They’re often combined with roasted barley.

  • Joel Santos

    I know that saturated fat is bad but what about lean cuts of meat? My family is cooking beef fillet steaks for lunch and I’m wondering if I should have my piece.

  • futuristvegan

    Cool video could u do one on this: interesting new story on diet of roman gladiators! Apparently the poor guys drank ‘tonic of ashes’ and were vegetarian

    Unsurprisingly there’s also alot of literature covering the benefits of a plant based diet for sustainability. That could also be interesting!

  • Beth Aaron

    I live in North Conway,NH and the local hospital, Memorial, has all these nice sounding health programs like Stanford based, “Better Choices, Better Health,” and soon to be a Women’s Breast Health Initiative, and CHOP, Community Health and Obesity Prevention…The town even created an ad hoc committee to look into health care cost reduction. I sat through several meetings and heard prevention mentioned maybe for two seconds , even from speakers who gave presentations on health and wellness which focused on everything but. It’s infuriating like dealing with addicts who refuse to end their addictions. Combined with emerging public health threats of communicable diseases, climate and environmental issues rooted in animal agriculture and resource depletion from it, how can these people ignore the largest looming threat to their own children, even though they spend whatever is necessary to ensure schools are safe?

  • Susan

    Retired Purdue University Professor Don Huber suggested that “Roundup Ready crops, treated with glyphosate, had higher levels of mycotoxins and lower nutrient levels than conventional crops. When consumed, the GM crops were more likely to cause disease, ‘infertility,’ birth defects, cancer and allergic reactions than conventional crops.”

    Read: Scientist raises concerns about GM crops and glyphosate: Cause of diseases?

  • Getting a good dental cleaning helps, too.

  • ckchick

    what about a male with Thyroid Stimulating Hormone issues that were found to be the cause of a zero sperm count. Does that factor rule out these findings as far as diet making an impact? (meaning, is there no hope for increasing sperm count because of the TSH level?)

    • Gar Zuzik

      I have never heard of this connection before. If the study is posted I am sure (toxins) or (largelytrue) can either confirm or refute the study’s credibility (they are rather good at that based on my observation.) :)

  • sf_jeff

    Sorry, I am not following part of this video. Could you give more info on the “Anti-oxidents in pill form may have adverse effects” part?

  • Gar Zuzik

    From a different perspective, as a 23yo, no one even close to my age ( -10, +30) cares about sperm count

  • ctkchic

    What about fertility issues that have been blamed on TSH level in a male? Would diet still play a role?