Thursday, November 4, 2010

Upcoming Interview with Dr. Mercola, the Wiki Bandits, Saturated Fat and Sperm Count, and More

by Chris Masterjohn

Next Thursday I'm Dr. Mercola is conducting a video interview with me over Skype that will be posted on his web site.  We're covering the subject of goitrogens, with specific reference to my Thyroid Toxins Special Report and with special emphasis on soy.

If you'd like Dr. Mercola to ask a specific question, you can recommend one by commenting on his Facebook status:

Dr. Joseph Mercola: Next Thursday I will be interviewing Chris Masterjohn who is an expert on soy. Would love to know what questions you would like me to ask him about soy.

Please keep the questions relevant to thyroid function!

Denise Minger's back at the blog, and noted that the vegans controlling the China Study Wikipedia page have not only eliminated the section about her criticisms, but have eliminated the links to my review, which have been up there for years.

Here's her post:

New Interview and More Sucky Science

She also briefly discusses a study a few people have emailed me about, claiming that saturated fat causes decreased sperm count and poor sperm mobility.  I have a few comments to add.

First, the study was presented at a conference, which probably means we won't be able to see the full data in published form for a few months.  However, the news reporting on this study seems to be of poor quality.  For example, this Medscape article (free registration required) states at the beginning that "a high intake of saturated and monounsaturated fat is associated with significantly low sperm concentration, whereas a high intake of healthier polyunsaturated fatty acids is associated with improved sperm motility and morphology," and states again that "men with the highest intake of saturated fat had as much as 41% fewer sperm than those with the lowest intake" but then states that multiple linear regression "showed that saturated fatty acid levels in sperm were inversely related to sperm concentration (r = −0.53); however, saturated fat intake was unrelated to sperm levels."

My best shot at interpreting this article is that saturated fat intake was associated with poor sperm concentrations in the unadjusted analysis, but that after adjusting for total energy intake, age, abstinence time, body mass index, smoking status, and intakes of caffeine and alcohol, the association disappeared.

So, apparently what we have is a finding that men with greater fertility problems have more saturated fat in their sperm.

Why might that be?

Well, as Ned Kock pointed out in the comments in Denise's blog, these people were overweight and infertile so they were probably insulin resistant.  Insulin resistance is generally associated with increased production of fat from carbohydrate in the liver.  What kind of fat does the liver make?  Saturated fat. 

There's an even more obvious reason why this may have been the case.  Take a look at this snippet from the Medscape article:
"Levels of fatty acids in the sperm are markers of sperm maturation, in general, with the amount of DHA increasing as the sperm matures and the total amount of fatty acids decreasing."
So as sperm mature, the level of PUFA goes up at the expense of all the other fatty acids.  In other words, as sperm mature, they get rid of their saturated fats.

So what does this study show?  That men with low sperm counts also have immature sperm. 

Big news! Call the press! 

Heck, this finding is so novel and important it deserves to be spread all over the internet.  I see the news reporters already got to that, but here's my part.

Read more about the author, Chris Masterjohn, PhD, here.


  1. Speaking of thyroid toxins, What do you think of diosgenin in yams? particularly dioscorea batatas or chinese yam. Apparently diosgenin has estrogenic effects, which makes me wonder if it's an acceptable food crop. Any help appreciated.

  2. I wonder if they crunched any numbers (or reported any crunches) for carb intake and sperm. I am thinking, overweight people probably tend to have a higher intake of everything including sat fat but also carbs. Or that eaters of processed food may have higher intake of sat fat as well as carbs. Anyways, kudos to you if you can make any sense out of what has been reported so far. Seems like many reporters feel no special need to actually understand or make much sense with what they write.

  3. Greensmu,

    Sorry, I'm not well researched on goitrogens in Chinese yams and unfortunately cannot answer your qeustion.


    That's a good point. Carbohydrates are much more effective at raising levels of saturated fat than saturated fat is. Or that is true for blood levels at least.


  4. Chris, any chance this interview is available as a podcast?

  5. Yikes. I love your content, but the frame-in-frame website design is horrendous!

  6. Tyler,

    It will be available on video on his site. I'll post the link when it's up.


    What are you referring to? If there is something user-unfriendly I can try to fix it.


  7. Hi Chris,

    I believe I know what Tyler means, and agree it would be better to do something different. On your main site, not this blog, any links you have to other sites open on your site so the content of the other site displays in a "frame" (correct me if I'm wrong about your complaint Tyler). Instead, you can set the external links to open in a new window. That way you won't lose your readers to the other sites if they click on those links, they can still click back to view your site easily because it's still open.