The disastrous results of a low-fat diet

Rob was never that committed to following the program in the first place.

I met Rob because of a modest heart scan score and consultation for a cholesterol abnormality. Rob had been cycled through all the statin agents by his primary care physician, all of which resulted in terrible muscle aches that he found intolerable.

I started out, as usual, characterizing his cholesterol abnormality with lipoprotein testing (NMR):

LDL particle number 1489 nmol/L
LDL cholesterol (Friedewald calculation) 143 mg/dl
Small LDL 52% of total LDL
HDL 50 mg/dl
Triglycerides 82 mg/dl

(LDL particle number is the emerging gold standard for LDL quantification, superior to calculated or Friedewald LDL cholesterol for prediction of cardiovascular events.)

Rob is a busy guy. After only a couple of brief visits, life and work got in the way and Rob let his attentions drift away from heart health. Since the information I provided made little impact on his thinking, he reverted to the low-fat diet his primary care doctor had originally prescribed and that he read about in magazines and food packages. He also ran out of the basic supplements I had advised, including fish oil and vitamin D, and just never restarted them.

A couple of years passed and Rob decided that just poking around on his own might not cut it. So he came back to the office. We repeated his NMR lipoprotein analysis:

LDL particle number 2699 nmol/L
LDL cholesterol (Friedewald calculation) 229 mg/dl
Small LDL 81% of total LDL
HDL 53 mg/dl
Triglycerides 78 mg/dl

Two years of a low-fat diet had caused Rob's LDL particle number to skyrocket by 81%, nearly all due to an explosion of small LDL. Recall that small LDL is more susceptible to oxidation, more inflammation-provoking, more adhesive--the form of LDL particles most likely to cause heart disease.

Also, note that, despite the enormous increase in small LDL, HDL and triglycerides remained favorable. This counters the popular rule-of-thumb offered by some that small LDL is not present when HDL is "normal."

Low-fat diets as commonly practiced are enormously destructive. In Rob's case, a low-fat diet caused both calculated Friedewald LDL as well as LDL particle number to increase dramatically. In many other people, low-fat diets increase calculated Friedewald LDL modestly or not at all, but cause the more accurate LDL particle number to increase significantly, all due to small LDL.

I'm happy to say that, once Rob witnessed how far wrong he could go on the wrong program, he's back on Track. (Sorry, pun intended.) He has resumed his supplements and eliminated the food triggers of small LDL--wheat, cornstarch, and sugars.

Comments (16) -

  • Jim Purdy

    11/4/2009 3:06:47 PM |

    Wheat, cornstarch, and sugars ... all have been out of my diet for a while now.

    I really appreciate the information and advice in your blog.

  • Nancy LC

    11/4/2009 6:02:11 PM |

    Dr. Davis,

    There's a belief in the low carb community that if triglycerides are low that LDL tends to be the large, buoyant sort that isn't problematic.  But this fellow's triglycerides are fairly low and clearly he has an issue.  What do you think?  Can one depend on having the harmless sort of LDL if you've cut out the grains and sugars?

  • 8bitpixel

    11/4/2009 9:09:41 PM |

    When can we expect an update on his numbers?

  • LPaForLife

    11/4/2009 9:54:12 PM |

    A low fat high carb diet reduced my HDL big time and didn't effect my total LDL much. This seems quite different from these results. I thought low fat usually reduces HDL. Am I wrong?

  • Jeff

    11/4/2009 10:05:49 PM |

    What are the sources of cornstarch? I can't think of anything that has cornstarch in it except, well, cornstarch.

  • Dr. William Davis

    11/4/2009 11:48:36 PM |

    Hi, Nancy--

    No, you cannot.

    Humans are a hodgepodge of varying genetic tendencies. While elimination of these small LDL triggering foods reduces small LDL, it doesn't always eliminate them, especially in the genetically predisposed.

  • Joe D

    11/5/2009 1:41:55 AM |

    I don't want to waste your time, but in case you don't know: I (and maybe others) received this email today. It was marked as "SPAM" but I opened it anyway since it had your name on it. If you didn't authorize it maybe you should mention it in your blog. Thanks. Joe.

    From: Dr. Davis - PharmaNutrients (email addressed followed) hilary at
    Subject: Dr. Davis recommends Cardio for optimal heart health
    Date: November 4, 2009 8:02:02 AM MST

  • AMK

    11/5/2009 6:55:57 AM |

    Supplements can be of great help in getting rid of free radicals  to our body.  A good source of vitamins and antioxidants to suffice what we lack from food intake.

  • Dave Brown

    11/5/2009 11:08:15 AM |

    Hello Dr.,

    So if after eliminating wheat, cornstarch and sugars the lipoprotein test still show a high percentage of small LDL particles (probably due to genetics) - What could be done next?

  • Dr. William Davis

    11/5/2009 4:08:37 PM |

    In my view, once wheat has been eliminated, it should stay that way. I've seen too many people explode in weight and lipid abnormalities with resumption of wheat. I liken it to stopping alcohol in an alcoholic--once "dry," I would not recommend a drink or two.

  • Dr. William Davis

    11/5/2009 4:09:34 PM |

    Hi, Dave--

    The reduction of small LDL after dietary changes are made is among the most difficult patterns of all the address. This is discussed in great detail in several reports and forums on

  • Bonnie

    11/5/2009 6:14:25 PM |

    I've been reading your blog for about a year.  I am fitness professional at a healthy weight, but have had issues with genetic moderately high cholesterol (including Lp(a)). High HDL, low Triglycerides, high end of normal LDL (mixed A/B size) AND several high liver enzymes for some unexplained reason (possibly NAFLD?).

    I finally eliminated wheat from my diet (95% of the time) about 8 months ago.  My recent blood work came back and the most profound change was that ALL of my LDL particles are now in the Large range, AND nearly all of my liver enzymes are within normal range for the first time!  An unexpected surprise!

    Could it be that my liver doesn't like wheat??  Go figure!  

    I am now a believer Smile

    Thanks for your educational blog!


  • Dr. William Davis

    11/6/2009 1:18:00 PM |

    Hi, Bonnie--

    That's great!


    Yes, it applies to females, as well.

  • Anonymous

    11/11/2009 8:22:00 PM |

    How do we know that these results aren't more about the "dangerous" foods than the times they were eaten? If this experiment had been done with a few slices of turkey and a big salad and a glass of milk, would the results have been the same?

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    1/27/2011 5:40:26 AM |

    Well, I don't believe that high carbohydrate diets are causing ADD, but I do feel that some ADDers may be especially sensitive to high insulin levels generated by the modern low fat diet.